M2 - Hi-Fi System MOTU - Free user manual and instructions
Find the device manual for free M2 MOTU in PDF.
| Product Type | USB Audio Interface / Hi-Fi System |
| Inputs | 2 combo XLR/TRS (mic, line, instrument) with 60 dB gain range |
| Outputs | 2 balanced 1/4" TRS (DC-coupled), 2 unbalanced RCA, 1 stereo headphone (1/4") |
| MIDI I/O | 5-pin DIN MIDI input and output |
| Phantom Power | +48V, switchable per channel for condenser microphones |
| Display | Full-color LCD (160x120 pixels) with level meters |
| Sample Rates | Up to 192 kHz |
| Bit Depth | 24-bit |
| Dynamic Range (inputs) | 115 dB (A-weighted) for mic inputs; 114 dB for instrument inputs |
| Dynamic Range (outputs) | 120 dB (A-weighted) for line outputs |
| Power Supply | USB bus-powered (USB-C or USB-A with adapter); no external power required |
| System Requirements | macOS 10.11+, Windows 10+ (x64), iOS with USB-C or Lightning adapter |
| Included Accessories | USB-C to USB-A cable, safety instruction sheet |
| Cleaning | Unplug and wipe with a dry cloth; do not use liquid or aerosol cleaners |
| Safety | Do not expose to rain or moisture; no user-serviceable parts inside; refer servicing to qualified personnel |
| Warranty | 2-year limited hardware warranty (requires registration within 90 days) |
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Download the instructions for your Hi-Fi System in PDF format for free! Find your manual M2 - MOTU and take your electronic device back in hand. On this page are published all the documents necessary for the use of your device. M2 by MOTU.
USER MANUAL M2 MOTU
1280 Massachusetts Avenue
Cambridge, MA 02138
Business voice: (617) 576-2760
Business fax: (617) 576-3609
Web site: www.motu.com
Tech support: www.motu.com/support
SAFETY PRECAUTIONS AND ELECTRICAL REQUIREMENTS FOR THE M2, M4 and M6 ("PRODUCT")
CAUTION! READ THIS SAFETY GUIDE BEFORE YOU BEGIN INSTALLATION OR OPERATION. FAILURE TO COMPLY WITH SAFETY INSTRUCTIONS COULD RESULT IN BODILY INJURY OR EQUIPMENT DAMAGE.

HAZARDOUS VOLAGES: CONTACT MAY CAUSE ELECTRIC SHOCK OR BURN. TURN OFF UNIT BEFORE SERVICING.
WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRICAL SHOCK, DO NOT EXPOSE THIS APPLIANCE TO RAIN OR OTHER MOISTURE.
CAUTION: TO REDUCE THE RISK OF ELECTRICAL SHOCK, DO NOT REMOVE COVER. NO USER-SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.
WARNING: DO NOT PERMIT FINGERS TO TOUCH THE TERMINALS OF PLUGS WHEN INSTALLING OR REMOVING THE PLUG TO OR FROM THE OUTLET.
WARNING: IF NOT PROPERLY GROUNDED THE MOTU PRODUCT COULD CAUSE AN ELECTRICAL SHOCK.
IMPORTANT SAFEGUARDS
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Read these instructions. All the safety and operating instructions should be read before operating the product.
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Keep these instructions. These safety instructions and the product owner's manual should be retained for future reference.
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Heed all warnings. All warnings on the product and in the owner's manual should be adhered to.
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Follow all Instructions. All operating and use instructions should be followed.
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Do not use the product near water.
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Cleaning - Unplug the product from the computer and clean only with a dry cloth. Do not use liquid or aerosol cleaners.
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Ventilation - Do not block any ventilation openings. Install in accordance with the manufacturer's instructions.
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Heat - Do not install the product near any heat sources such as radiators, heat registers, stoves, or another apparatus (including an amplifier) that produces heat.
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Overloading - Do not overload wall outlets and extension cords as this can result in a risk of fire or electrical shock.
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Power cord - Protect the product power cord from being walked on or pinched by items placed upon or against them. Pay particular attention to cords and plugs, convenience receptacles, and the point where they exit from the unit.
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Power switch - Install the product so that the power switch can be accessed and operated at all times.
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Disconnect - The main plug is considered to be the disconnect device for the product and shall remain readily operable.
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Accessories - Only use attachments/accessories specified by the manufacturer.
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Placement - Use only with the cart, stand, tripod, bracket or table specified by the manufacturer, or sold with the product. When a cart is used, use caution when moving the cart/apparatus combination to avoid injury from tip-over.
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Surge protection - Unplug the product during lightning storms or when unused for long periods of time.
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Servicing - Refer all servicing to qualified service personnel. Servicing is required when the product has been damaged in any way, such as when a power-supply cord or plug is damaged, liquid has been spilled or objects have fallen into the product, the product has been exposed to rain or moisture, does not operate normally, or has been dropped.
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Power Sources - Refer to the manufacturer's operating instructions for power requirements. Be advised that different operating voltages may require the use of a different line cord and/or attachment plug.
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Installation - Do not install the product in an unventilated rack, or directly above heat-producing equipment such as power amplifiers. Observe the maximum ambient operating temperature listed below.
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Power amplifiers- Never attach audio power amplifier outputs directly to any of the unit's connectors.
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Replacement Parts - When replacement parts are required, be sure the service technician has used replacement parts specified by the manufacturer or have the same characteristics as the original part. Unauthorized substitutions may result in fire, electric shock or other hazards.
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Safety Check - Upon completion of any service or repairs to this MOTU product, ask the service technician to perform safety checks to determine that the product is in safe operating conditions.
ENVIRONMENT, HEAT AND VENTILATION
Operating Temperature: 10°C to 40°C (50°F to 104°). The product should be situated away from heat sources or other equipment that produces heat. When installing the product in a rack or any other location, be sure there is adequate space around the product to ensure proper ventilation. Improper ventilation will cause overheating and can damage the unit.
TO REDUCE THE RISK OF ELECTRICAL SHOCK OR FIRE
Do not handle the power cord with wet hands. Do not expose this apparatus to rain or moisture. Do not place objects containing liquids on it.



This equipment has been type tested and found to comply with the limits for a class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause interference to radio or television equipment reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by any combination of the following measures:
- Relocate or reorient the receiving antenna
- Increase the separation between the equipment and the receiver
- Plug the equipment into an outlet on a circuit different from that to which the receiver is connected
If necessary, you can consult a dealer or experienced radio/television technician for additional assistance.
PLEASE NOTE: only equipment certified to comply with Class B (computer input/output devices, terminals, printers, etc.) should be attached to this equipment, and it must have shielded interface cables in order to comply with the Class B FCC limits on RF emissions.
WARNING: changes or modifications to this unit not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment.

Contents
5 Quick Start Guide
7 M2 Quick Reference
8 M4 Quick Reference
9 M6 Quick Reference
10 Packing List and System Requirements
11 Software Installation
15 Hardware Installation
21 Working with Host Audio Software
25 Troubleshooting
27 Audio Specifications
29Index
About the Mark of the Unicorn License Agreement and Limited Warranty on Software
TO PERSONS WHO PURCHASE OR USE THIS PRODUCT: carefully read all the terms and conditions of the "click-wrap" license agreement presented to you when you install the software. Using the software or this documentation indicates your acceptance of the terms and conditions of that license agreement.
Mark of the Unicorn, Inc. ("MOTU") owns both this program and its documentation. Both the program and the documentation are protected under applicable copyright, trademark, and trade-secret laws. Your right to use the program and the documentation are limited to the terms and conditions described in the license agreement.
REMINDER OF THE TERMS OF YOUR LICENSE
This summary is not your license agreement, just a reminder of its terms. The actual license can be read and printed by running the installation program for the software. That license agreement is a contract, and clicking "Accept" binds you and MOTU to all its terms and conditions. In the event anything contained in this summary is incomplete or in conflict with the actual click-wrap license agreement, the terms of the click-wrap agreement prevail.
YOU MAY: (a) use the enclosed program on a single computer; (b) physically transfer the program from one computer to another provided that the program is used on only one computer at a time and that you remove any copies of the program from the computer from which the program is being transferred; (c) make copies of the program solely for backup purposes. You must reproduce and include the copyright notice on a label on any backup copy.
YOU MAY NOT: (a) distribute copies of the program or the documentation to others; (b) rent, lease or grant sublicenses or other rights to the program; (c) provide use of the program in a computer service business, network, time-sharing, multiple CPU or multiple user arrangement without the prior written consent of MOTU; (d) translate, adapt, reverse engineer, decompile, disassemble, or otherwise alter the program or related documentation without the prior written consent of MOTU.
MOTU warrants to the original licensee that the disk(s) on which the program is recorded be free from defects in materials and workmanship under normal use for a period of ninety (90) days from the date of purchase as evidenced by a copy of your receipt. If failure of the disk has resulted from accident, abuse or misapplication of the product, then MOTU shall have no responsibility to replace the disk(s) under this Limited Warranty.
THIS LIMITED WARRANTY AND RIGHT OF REPLACEMENT IS IN LIEU OF, AND YOU HEREBY WAIVE, ANY AND ALL OTHER WARRANTIES, BOTH EXPRESS AND IMPLIED, INCLUDING BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE LIABILITY OF MOTU PURSUANT TO THIS LIMITED WARRANTY SHALL BE LIMITED TO THE REPLACEMENT OF THE DEFECTIVE DISK(S), AND IN NO EVENT SHALL MOTU OR ITS SUPPLIERS, LICENSORS, OR AFFILIATES BE LIABLE FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES, INCLUDING BUT NOT LIMITED TO LOSS OF USE, LOSS OF PROFITS, LOSS OF DATA OR DATA BEING RENDERED INACCURATE, OR LOSSES SUSTAINED BY THIRD PARTIES EVEN IF MOTU HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. THIS WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS WHICH MAY VARY FROM STATE TO STATE. SOME STATES DO NOT ALLOW THE LIMITATION OR EXCLUSION OF LIABILITY FOR CONSEQUENTIAL DAMAGES, SO THE ABOVE LIMITATION MAY NOT APPLY TO YOU.
UPDATE POLICY
In order to be eligible to obtain updates of the program, you must complete and return the attached Mark of the Unicorn Purchaser Registration Card to MOTU.
COPYRIGHT NOTICE
Copyright © 2022, 2021, 2020, 2019 by Mark of the Unicorn, Inc. All rights reserved. No part of this publication may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any human or computer language, in any form or by any means whatsoever, without express written permission of Mark of the Unicorn, Inc., 1280 Massachusetts Avenue, Cambridge, MA, 02138, U.S.A.
Limited Warranty on Hardware
Mark of the Unicorn, Inc. ("MOTU") warrants this equipment against defects in materials and workmanship under normal use for a period of TWO (2) YEARS from the date of original retail purchase. The Warranty Term begins on the date of purchase from an authorized MOTU reseller and applies solely to the original retail purchaser, who must activate the warranty by creating a user account at motu.com to register the product within 90 days of purchase. This warranty applies only to hardware products; MOTU software is licensed and warranted pursuant to separate written statements.
If you discover a defect, first contact MOTU technical support by phone, email or web (motu.com/support) to verify the warranty on your MOTU equipment and obtain a Return Merchandise Authorization (RMA). No service will be performed on any product returned without prior authorization. MOTU will, at its option, repair or replace the product at no charge to you, provided you return it during the warranty period as instructed by MOTU, with transportation charges prepaid. If you purchased your equipment in any country other than the US or Canada, you will be instructed to return the equipment to an authorized MOTU distributor or representative in the country of purchase. You must use the product's original packing material for the shipment, and insure the shipment for the value of the product. Please include your name, address, phone number, email address, a description of the problem, and the original, dated bill of sale with the returned unit; do NOT include additional accessories such as cables, power supplies, manuals, etc. Please clearly print the Return Merchandise Authorization Number on the outside of the box below the shipping address. Repaired or replaced equipment will be returned to you via UPS Ground prepaid. (Expedited shipping methods such as UPS next day, 2-day, and 3-day services are available for an additional cost.) Repaired equipment will be warranted for a period equal to the remainder of the original Limited Warranty or for 90 days, whichever is longer.
WARRANTY EXCLUSIONS: This warranty does not apply if the equipment has been damaged by accident, abuse, misuse, or misapplication; has been modified without the written permission of MOTU; or if the product serial number has been removed or defaced. The following examples, without limitation, are NOT covered by this hardware warranty:
• Equipment purchased through any reseller not directly authorized by MOTU or its authorized international distributors.
- "Used" equipment purchased from a third party.
• Equipment purchased in another country.
- Normal cosmetic and mechanical wear of the equipment.
• Equipment damaged by improper installation or connections.
• Equipment damaged in transit to/from MOTU for warranty repair.
• Physically damaged equipment, including but not limited to water damage, cracks or dents, missing or bent parts, burns or other damage caused by faulty or failed electric power
ALL IMPLIED WARRANTIES, INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE LIMITED IN DURATION TO TWO (2) YEARS FROM THE DATE OF THE ORIGINAL RETAIL PURCHASE OF THIS PRODUCT. THE WARRANTY AND REMEDIES SET FORTH ABOVE ARE EXCLUSIVE AND IN LIEU OF ALL OTHERS, ORAL OR WRITTEN, EXPRESS OR IMPLIED. No MOTU dealer, agent, or employee is authorized to make any modification, extension, or addition to this warranty. MOTU IS NOT RESPONSIBLE FOR SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES RESULTING FROM ANY BREACH OF WARRANTY, OR UNDER ANY LEGAL THEORY, INCLUDING LOST PROFITS, DOWNTIME, GOODWILL, DAMAGE OR REPLACEMENT OF EQUIPMENT AND PROPERTY AND COST OF RECOVERING REPROGRAMMING, OR REPRODUCING ANY PROGRAM OR DATA STORED IN OR USED WITH MOTU PRODUCTS.
Some states do not allow the exclusion or limitation of implied warranties or liability for incidental or consequential damages, so the above limitation or exclusion may not apply to you. This warranty gives you specific legal rights, and you may have other rights which vary from state to state.
Manual version 2.00
Quick Start Guide
Thank you for purchasing an M series USB interface! Follow these easy steps to get started quickly.
FOR MAC USERS
1 Connect the M series interface to your Mac using the included USB cable.
If your computer has USB-C ports, use a USB-C to USB-C cable (rated for USB2), or a USB-C to USB-A adapter, (both sold separately).
2 Go to the Apple menu and choose System Preferences.
3 Click Sound and choose the M2, M4 or M6 as the input and output device.

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Sound Sound Effects Output Input Select a device for sound output: Name Type Display Audio USB M4 USB MacBook Pro Speakers Built-in Settings for the selected device: The selected device has no output controls Output volume: Show volume in menu bar4 Go to Step 5 below.
FOR WINDOWS USERS
1 BEFORE you connect the M series interface to your computer, visit motu.com/m2-start, motu.com/m4-start or motu.com/m6-start to download and install the Windows driver.
2 Connect the M series interface to your PC using the included USB cable.
If your computer has USB-C ports, use a USB-C to USB-C cable (rated for USB2), or a USB-C to USB-A adapter, (both sold separately).
3 Go to the Windows Sound Control Panel and choose MOTU M Series as the default input and output device.

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Settings Home Find a setting System Display Sound Notifications & actions Focus assist Power & sleep Battery Sound Output Choose your output device Out 1-2 (2- M3TU M Series) Certain apps may be set up to use different sound devices than the one selected here. Customize app volumes and devices in advanced sound options. Device properties Master volume d4 53 Troubleshoot Manage sound devices4 Go to Step 5 below.
FOR ALL USERS
5 Connect speakers and/or a pair of headphones to the M series interface so you can hear your computer's audio output. For speakers, connect them to the outputs on the back panel.
6 You are now ready to start using your M series interface.
7 Visit motu.com/m2-start, motu.com/m4-start or motu.com/m6-start to register your product, download the included software and watch brief how-to videos, including:
■ How to connect a mic, guitar, keyboard or other line-level audio source.
■ How to use your M series interface with your recording software.
■ How to get the most out of your M series interface.
PLEASE REGISTER TODAY
Please visit motu.com/m2-start, motu.com/m4-start or motu.com/m6-start to register your M series interface and gain access to all the software, virtual instruments, loops and sounds that are included with your purchase. Registered users also qualify for technical support and information about software updates, so please register today!
Thank you for taking the time to register your new MOTU product!
FINDING YOUR SERIAL NUMBER
You can find your M series product serial number on the bottom of the unit and the side of the box.
M2 Quick Reference

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IN 1L GAIN MIO / LINE / OUTAR IN 2R GAIN MIO / LINE / OUTAR MOTU IN OUT MONITOR 1 - 2 1 2 8 7 6 9 10 11 I O MIDI IN OUT MOTU M2 USB-C 1 (L) 2 (R) MONITOR 13- These two XLR/TRS combo jacks accept a mic cable or a quarter-inch cable, balanced or unbalanced, from a guitar or line level source.
- Use GAIN knob to add up to 60 dB of boost to the input signal. Watch the input level meter in the LCD while adjusting gain. Try to adjust gain as high as possible without clipping, which is indicated by the red rectangle at the top of the meter.
- The full-color, high-resolution LCD (160x120 pixels) shows full-length meters for all inputs and outputs. An overloaded signal is indicated by a red box at the top of the signal. If you see the red box, reduce the signal level. A blue box around the input channel number indicates that hardware (direct) monitoring (the MON button) is engaged for that channel.
- Volume control for the MONITOR outputs on the back panel.
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Volume control for headphone output.
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Connect your headphones here. This signal matches the signal on the MONITOR outputs on the rear panel, but volume control (5) is independent.
- Engage the 48V button to turn on phantom power for a condenser microphone connected to the input.
- Engage the MON (monitor) button to enable hardware (direct) monitoring, which routes the channel's input signal directly to the outputs and pans the mono signal evenly across both outputs (1-2). A blue box appears around the input channel number in the LCD to indicate that hardware monitoring is engage. Press and hold the MON button to engage stereo monitoring for both inputs. In this mode, Input 1 is routed to Output 1 and Input 2 is routed to Output 2, allowing you to monitor in stereo while recording in stereo.
- POWER SWITCH: You can switch off the M2 and turn it back on without restarting your computer.
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Connect MIDI gear to these standard MIDI ports.
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These unbalanced RCA analog outputs mirror the signal on the quarter-inch outputs (12). You can connect them to a second set of speakers or other destination.
- Connect these balanced, DC-coupled quarter-inch outputs to your studio speakers, PA or other desired audio destination. They can also accept an unbalanced plug.
Note: the analog outputs are not cross-coupled. Therefore, when connecting them to an unbalanced input, use a TRS plug with the ring disconnected. Not floating the negative terminal will short it to the sleeve ground and cause distortion.
- Connect the M2 to your host computer with the supplied USB-C to USB-A cable. If your computer has USB-C ports, use a USB-C to USB-C cable (rated for USB2) or a USB-A adapter (both sold separately). The M2 is powered by its USB connection to the host computer. For information about connecting to an iOS device, see "Connecting to an iOS device" on page 18.
M4 Quick Reference

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IN 1L GAIN MIO / LINE / OUTAR IN 2R GAIN MIO / LINE / OUTAR INPUT PMTBACK INPUT MONITOR MIX 3-4 MOTU IN OUT MONITOR 79 11 12 13 15 MIDI MOTU M4 IN OUT USB-C USB POWERED 3 (L) 4 (R) LINE OUT MONITOR LINE OUT MONITOR LINE IN- These two XLR/TRS combo jacks accept a mic cable or a quarter-inch cable, balanced or unbalanced, from a guitar or line level source.
- Use GAIN knob to add up to 60 dB of boost to the input signal. Watch the input level meter in the LCD while adjusting gain. Try to adjust gain as high as possible without clipping, which is indicated by the red rectangle at the top of the meter.
- INPUT MONITOR MIX: Controls the balance (relative volume) between computer output (over USB) and live inputs being monitored through the hardware using the MON (monitor) button (10). Turn it counterclockwise to hear more inputs; turn it clockwise to hear more computer audio.
- The full-color, high-resolution LCD (160x120 pixels) shows full-length meters for all inputs and outputs. An overloaded signal is indicated by a red box at the top of the signal. If you see the red box, reduce the signal level. A blue box around the input channel number indicates that hardware (direct) monitoring (the MON button) is engaged for that channel.
- Volume control for the MONITOR outputs on the back panel.
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Volume control for headphone output.
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Connect your headphones here. This signal matches the signal on the MONITOR outputs on the rear panel, but volume control (6) is independent.
- Engages hardware (direct) monitoring for inputs 3-4 on the rear panel. See (10) below for more information.
- Engage the 48V button to turn on phantom power for a condenser microphone connected to the input.
- Engage the MON (monitor) button to enable hardware (direct) monitoring, which routes the channel's input signal directly to the outputs and pans the mono signal evenly across both outputs (1-2). A blue box appears around the input channel number in the LCD to indicate that hardware monitoring is engage. Press and hold the MON button to engage stereo monitoring for both inputs. In this mode, Input 1 is routed to Output 1 and Input 2 is routed to Output 2, allowing you to monitor in stereo while recording in stereo.
- POWER SWITCH: You can switch off the M4 and turn it back on without restarting your computer.
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Connect MIDI gear to these standard MIDI ports.
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These unbalanced RCA analog outputs mirror the signal on their corresponding quarter-inch outputs (14). You can connect them to a second set of speakers or other destinations.
- Connect these balanced, DC-coupled quarter-inch outputs to your studio speakers, PA or other desired audio destination. They can also accept an unbalanced plug. Each output pair is independent and can be found as separate output pairs in your host software.
Note: the analog outputs are not cross-coupled. Therefore, when connecting them to an unbalanced input, use a TRS plug with the ring disconnected. Not floating the negative terminal will short it to the sleeve ground and cause distortion.
- These LINE INPUTS accept either a balanced or unbalanced plug. Connect a keyboard or other similar line level audio source.
- Connect the M4 to your host computer with the supplied USB-C to USB-A cable. If your computer has USB-C ports, use a USB-C to USB-C cable (rated for USB2) or a USB-A adapter (both sold separately). The M4 is powered by its USB connection to the host computer.
M6 Quick Reference

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16 2 3 4 5 MOTU 3-4 48V 48V 48V 48V MON MON MON INPUT PLAYBACK A/B MON 5-6 IN 3-4 5-6 1-2 3-4 1-2 3-4 MONITOR 81 13 14 15 18 IN MIDI OUT USB-C 15V DC BUS POWERED (USB-C HOST ONLY) LINE OUT MONITOR LINE IN MIC / LINE / GUITAR 20 19- Use these GAIN knobs to add up to 60 dB of boost to the input signal for each mic input. Watch the input level meter in the LCD while adjusting gain. Try to adjust gain as high as possible without clipping, which is indicated by the red rectangle at the top of the meter.
- INPUT MONITOR MIX: Controls the balance (relative volume) between computer output (over USB) and live inputs being monitored through the hardware using the MON (monitor) button (12). Turn it counterclockwise to hear more inputs; turn it clockwise to hear more computer audio.
- The full-color, high-resolution LCD (160x120 pixels) shows full-length meters for all inputs and outputs. An overloaded input signal is indicated by a red box at the top of the signal. If you see the red box, reduce the signal level. A blue box around the input channel number indicates that hardware (direct) monitoring (the MON button) is engaged for that channel.
- Volume control for the MONITOR outputs on the back panel. If you are using the A/B speaker select mode, this controls the volume of either your A speakers or B speakers (whichever is currently selected).
- Volume control for headphone output below it.
- Both headphone outputs mirror the signal on the MONITOR 1-2 outputs (on the rear panel). Engage the 3-4 switch to monitor LINE OUT 3-4 instead on this headphone output. This allows you to set up a separate mix from your host software for this headphone output.
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Volume control for headphone output below it.
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Connect your headphones here. This signal matches the signal on the MONITOR 1-2 outputs on the rear panel, but volume control (5 and 7) is independent.
- Engages hardware (direct) monitoring for inputs 5-6 on the rear panel. See (12) below for more information.
- Press and hold the A/B switch to enable or disable A/B mode. When enabled, you can connect a 2nd pair of "B" monitors to Line Out 3-4. Then, quickly press the A/B button to switch between the A monitors (connected to MONITOR Outs 1-2) and the B monitors (connected to Line Out 3-4) to compare your mix on the two sets of monitors. For details, see "A/B monitor switching on the M6" on page 19.
- Engage the 48V button to turn on phantom power for a condenser microphone connected to the input.
- Engage the MON (monitor) button to enable hardware (direct) monitoring, which routes the channel's input signal directly to the MONITOR 1-2 outputs and pans the mono signal evenly across both outputs. A blue box appears around the input channel number in the LCD to indicate that hardware monitoring is engage. Press and hold the MON button to engage stereo monitoring for input pairs. In this mode, Input 1 is routed to Output 1 and Input 2 is routed to Output 2, allowing you to monitor in stereo while recording in stereo. Inputs 3-4 are similarly routed to Outputs 1 and 2 (3 to 1 and 4 to 2).
- POWER SWITCH: You can switch off the M6 and turn it back on without restarting your computer.
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Connect MIDI gear to these standard MIDI ports.
-
Connect these balanced, DC-coupled quarter-inch outputs to your secondary (B) studio speakers, PA or other desired audio destination. They can also accept an unbalanced plug (see the note below about unbalanced connections). Each output pair is independent and can be found as separate output pairs in your host software.
- Connect these balanced, DC-coupled quarter-inch outputs to your primary (A) studio speakers, PA or other desired audio destination. They can also accept an unbalanced plug. Each output pair is independent and can be found as separate output pairs in your host software.
Note: the analog outputs are not cross-coupled. Therefore, when connecting them to an unbalanced input, use a TRS plug with the ring disconnected. Not floating the negative terminal will short it to the sleeve ground and cause distortion.
- These LINE INPUTS accept either a balanced or unbalanced plug. Connect a keyboard or other similar line level audio source.
- These four XLR/TRS combo jacks accept a mic cable or a quarter-inch cable, balanced or unbalanced, from a guitar or line level source.
- Connect the M6 to your host computer with the supplied USB cable. When the M6 is connected to a USB-C host computer or iPad, it can be powered by its USB connection to the host. When connected to a USB-A host computer, you'll need to connect the DC power adapter to supply enough power.
- Connect the DC power adapter here. It is optional, unless the M6 is connected to a USB-A host that cannot supply enough bus power. You can also power the M6 when no host is connected.
CHAPTER 1 Packing List and System Requirements
PACKING LIST
M series interfaces ship with the items listed below. If any of these items are not present in the box when you first open it, please immediately contact your dealer or MOTU.
■ One M2, M4 or M6 audio interface
■ USB-C to USB-A cable
■ DC power adapter (M6 only)
■ Safety instruction sheet
SYSTEM REQUIREMENTS
Intel Core i3 Mac or faster (including Apple silicon Macs) or 1 GHz Pentium-based PC (or compatible). Faster CPUs are recommended for best performance.
■ 2 GB RAM; 4 GB or more recommended.
■ macOS 10.11 or later (optional driver requires 10.13 or later); Windows 10 or later (x64 only).
■ Available high-speed USB 2.0 (or 3.0) port.
■ A large hard drive (preferably at least 512 GB).
PLEASE REGISTER TODAY!
Please visit the link below that applies to you to register your M series interface and gain access to all the software, virtual instruments, loops and sounds that are included with your purchase.
Registered users also qualify for technical support and information about software updates, so please register today!
■ motu.com/m2-start
■ motu.com/m4-start
■ motu.com/m6-start
Thank you for taking the time to register your new MOTU product!
FINDING YOUR SERIAL NUMBER
You can find your M series product serial number on the bottom of the unit and the side of the box.
CHAPTER 2 Software Installation
OVERVIEW
USB audio class-compliant operation .... 11
Driver installation 11
M series Control Panel (Windows only) 12
MIDI I/O on Windows 13
MIDI I/O setup on the Mac....13
Working with host audio software....14
USB AUDIO CLASS-COMPLIANT OPERATION
Your M Series interface is a USB audio class-compliant device. This means that you can connect it to your Mac (running macOS 10.11 or higher) with a USB cable and use it without installing any software drivers. The computer recognizes your M Series interface as a USB audio device and makes its inputs and outputs available to your host audio software. Basic settings, such as the hardware's sample rate, are made in your host software.
In this scenario, your M Series interface provides basic audio input and output, and no software driver installation is necessary. Use the Mac's Audio MIDI Setup utility to manage your M Series interface audio inputs and outputs for your Mac.
Connection to iOS devices (iPad and iPhone)
Audio-class compliant operation allows you to connect your M Series interface to any iOS device to provide multi-channel audio I/O to your audio apps. Use your audio app to configure the number of available audio channels.
For iOS devices with a USB-C port, a USB-C to USB-C cable is required.
For iOS devices with a Lightning port, an Apple Lightning to USB3 Camera Adapter is required (sold separately).
DRIVER INSTALLATION
Driver installation is required for either of the following scenarios:
■ You are using a PC running Windows (10 or later).
- You are using a Mac and you wish to take advantage of the extra features that the driver provides: lower latency performance and loopback channels (see “Loopback” on page 23).
If neither scenario applies to you, then you can skip software installation if you wish, and proceed to chapter 3, “Hardware Installation” (page 15).
Download and run the M Series installer
To download the latest M Series installer for Mac or Windows, visit www.motu.com/m2-start (it's the same installer for the M2, M4 and M6). Follow the directions that the installer gives you.
We recommend that you run the software installer before you connect your M Series interface to your computer and power it on.
Industry-leading I/O latency performance
On macOS and Windows, the M series driver provides exceptionally low I/O latency performance. For example, with a 32-sample buffer size, an M Series interface operating at 96 kHz produces round trip latency (RTL) performance of 2.5 milliseconds (ms) on Windows and 2.5 ms on macOS. RTL is the measurement of the time it takes audio to pass from an analog input, through a DAW host, to an analog output.
M Series Core Audio driver for macOS
On macOS, to enable your M Series interface in your Core Audio-compatible host software, go to the menu item or preference in your host audio software where you choose the audio device (Core Audio driver) you wish to use, and then select the M2, M4 or M6 by name.

text_image
Configure Hardware Driver CoreAudio DisplayPort: Display Audio MacBook Pro Microphone MacBook Pro Speakers M2 Master Device: M2 Sample Rate: 48000 Clock Modes: M2 Buffer Size: 256 Work Priority: High Cancel OKFigure 2-1: Choosing the M Series Core Audio driver in Performer Lite on Windows (Setup menu > Configure Audio System > Configure Hardware Driver).
M Series ASIO driver for Windows (x64 only)
On Windows, to enable your M Series interface in your ASIO host software, choose M Series ASIO driver.

text_image
Configure Hardware Driver ASIO ASIO Driver: MOTU M Series Sample Rate: 45000 Clock Source: Internal Configure Driver Override internal buffer size 256 Priority Boost Cancel OKFigure 2-2: Choosing the M Series ASIO driver in Performer Lite on Windows (Setup menu > Configure Audio System > Configure Hardware Driver).
M SERIES CONTROL PANEL (WINDOWS ONLY)
On Windows, you can access the M Series control panel in the Windows Start menu. In Performer Lite, you can access it by clicking the Configure Driver button shown in Figure 2-2.

text_image
MOTU M-Series MOTU M SERIES Open this window when hardware is connected Sample Rate (Hz) Buffer Size (Samples) 48000 256 Use lowest latency safety offsets Sync Windows sample rate to device Device detected: M6 (m6ae003730) Firmware version: 2.00 Driver Version: 4.0.9.2185Figure 2-3: M Series control panel.
Sample Rate (Hz)
Choose the desired sample rate (Figure 2-3) for operation with your host software. Make sure your host software matches the sample rate you choose here.
Buffer Size
The Buffer Size setting (Figure 2-1 and Figure 2-3) determines the amount of latency (delay) you may hear when live audio is patched through your host audio software. Smaller buffer sizes produce lower latency, with sizes of 256 samples or less producing virtually imperceptible delay. Many host applications report audio hardware I/O latency, so you can see what happens to the reported latency when making adjustments to this setting.
Be careful with very small buffer sizes, as they can cause performance issues from your host software or PC.
At sea level, audio travels approximately one foot (30 cm) per millisecond. A latency of ten milliseconds is about the same as being ten feet (three meters) from an audio source.
Use lowest latency safety offsets
Enable the Use lowest latency safety offsets option (Figure 2-3) for the best possible low-latency performance from the driver. Note: some computer systems may not handle this option well. If you hear artifacts in your audio (clicks, pops, glitches, etc.), disable this option.
Sync Windows sample rate to device
Enable the Sync Windows sample rate to device option (Figure 2-3) to link this sample rate setting with the Sample Rate setting in Windows. This option is enabled by default for best performance with many Windows audio applications.
MIDI I/O ON WINDOWS
On Windows, the M Series driver installer provides a USB MIDI driver for your M Series interface. This driver allows you to access the their MIDI input and output ports through its USB connection to the computer. The ports are published in Windows and are available to all MIDI software.
MIDI I/O SETUP ON THE MAC
Core MIDI is the “under-the-hood” component of macOS that handles MIDI services for MIDI hardware and software. Core MIDI provides many universal MIDI system management features, including MIDI communication between your M Series interface and all Core MIDI compatible software.
Audio MIDI Setup is a utility included with macOS that allows you to configure your M Series interface for use with all Core MIDI compatible applications. Audio MIDI Setup provides:
■ A “virtual” studio on your Mac that graphically represents your MIDI hardware setup and that is shared by all Core MIDI-compatible programs
■ A simple, intuitive list of your MIDI devices whenever you need it in any Core MIDI-compatible program
Launching Audio MIDI Setup
1 Make sure your M Series interface is connected (a USB connection is required) and turned on.
2 Launch the Audio MIDI Setup utility.
This can usually be found in /Applications/ Utilities. If it has been moved, just search for Audio MIDI Setup.
3 Confirm that the MIDI interface is present in the MIDI Devices tab (or window) in Audio MIDI Setup. If the interface does not appear, or if it is grayed out, check your cable connections and click Rescan MIDI.
Connecting MIDI devices to the M Series
Once your M Series interface appears in Audio MIDI Setup, you are ready to add devices, indicate how they are connected, and identify properties they may have for particular purposes. This information is shared with all Core MIDI compatible applications.
To add a device in Audio MIDI Setup:
1 Click Add Device.
2 Drag on its input and output arrows to draw connections to the M Series interface that match its physical connection.

flowchart
graph TD
A["Bluetooth"] --> B["IAC Driver"]
C["Network"] --> B
D["M2"] --> E["Voice"]
F["Sound module"] --> E
G["External MIDI keyboard"] --> E
Figure 2-4: Connecting devices to an M Series interface. In this example, a controller keyboard is connected to the M2 MIDI IN, and a sound module is connected to the M2 MIDI OUT.
3 Double-click the device to make settings, such as input and output channels, that further describe the device.

text_image
External MIDI keyboard Properties Device Name: External MIDI keyboard Manufacturer: Model: Open Icon Browser Less Information ▲ Properties Ports Transmits Channels (max 16) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 MIDI Beat Clock MIDI Time Code Receives Channels (max 16) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 MIDI Beat Clock MIDI Time Code Features General MIDI MIDI Machine Control System Exclusive ID: Revert ApplyFigure 2-5: Device settings.
4 Repeat the above steps for each MIDI device connected to the interface.
5 When you are finished, quit Audio MIDI Setup.
Your configuration is automatically saved as the default configuration, and it is shared with all Core MIDI-compatible software.
WORKING WITH HOST AUDIO SOFTWARE
For further information about using your M Series interface with host audio software, see chapter 4, "Working with Host Audio Software" (page 21).
CHAPTER 3 Hardware Installation
A TYPICAL M2 SETUP

flowchart
graph TD
A["Headphones"] --> B["MOTU"]
B --> C["IN 1L/2L/3L/4L/5L/6L/7L/8L/9L/10L/11L/12L/13L/14L/15L/16L/17L/18L/19L/20L/21L/22L/23L/24L/25L/26L/27L/28L/29L/30L/31L/32L/33L/34L/35L/36L/37L/38L/39L/40L/41L/42L/43L/44L/45L/46L/47L/48L/49L/50L/51L/52L/53L/54L/55L/56L/57L/58L/59L/60L/61L/62L/63L/64L/65L/66L/67L/68L/69L/70L/71L/72L/73L/74L/75L/76L/77L/78L/79L/80L/81L/82L/83L/84L/85L/86L/87L/88L/89L/MOTU M2/MOTU<br> subgraph Headphones<br> direction LR<br> B -->|IN| C<br> B -->|OUT| D<br> B -->|MOTOR| E<br> B -->|MOTOR| F<br> B -->|MOTOR| G<br> end<br> subgraph Speakers<br> direction LR<br> H --> I[MIDI controller or synthesizer"]
H --> J["MIDI synth"]
H --> K["DJ system"]
H --> L["Mac or PC"]
H --> M["Speaker"]
end
Figure 3-1: A typical M2 studio setup.
A TYPICAL M4 SETUP

flowchart
graph TD
A["Mic or Guitar"] --> B["Headphones"]
C["Mic or Guitar"] --> B
D["MOTU"] --> B
E["MOTU M4"] --> B
F["MIDI controller or synthesizer"] --> G["MIDI synth"]
H["Mac or PC"] --> I["DJ system"]
J["B speakers"] --> K["A speakers"]
L["MIDI controller or synthesizer"] --> K
B --> M["NOTER"]
B --> N["NOTER"]
B --> O["NOTER"]
B --> P["NOTER"]
B --> Q["NOTER"]
B --> R["NOTER"]
B --> S["NOTER"]
B --> T["NOTER"]
B --> U["NOTER"]
B --> V["NOTER"]
B --> W["NOTER"]
B --> X["NOTER"]
B --> Y["NOTER"]
Figure 3-2: A typical M4 studio setup.
A TYPICAL M6 SETUP

flowchart
graph TD
A["MIDI controller or synthesizer"] --> B["Headphones"]
A --> C["Headphones"]
B --> D["MIDI synth"]
C --> D
D --> E["MIDI controller or synthesizer"]
E --> F["Mic or Guitar"]
E --> G["Mic or Guitar"]
E --> H["Mic or Guitar"]
E --> I["Mic or Guitar"]
F --> J["Power adapter (Only required for USB-A hosts)"]
G --> K["Mac or PC"]
H --> L["B speakers"]
I --> M["A speakers"]
J --> N["Mid/LINE/Guitar"]
K --> N
L --> N
M --> N
Figure 3-3: A typical M6 studio setup.
CONNECTING TO A MAC OR PC
Connect the M Series interface to your host computer with the supplied USB-C to USB-A cable. If your computer has USB-C ports, use a USB-C to USB-C cable (rated for USB2) or a USB-A adapter (both sold separately).
POWER
The M2 and M4 are powered by the USB connection to the host computer. The power requirements for the M6 depend on the host computer or iOS device, as follows:
Host Type Power source
| Computer with a USB-C port USB connection (or, optionally, the power adapter) |
| Computer with a USB-A port Power adapter (required) |
| iOS device with USB-C port USB connection (or, optionally, the power adapter) |
| iOS device with Lightning port USB3 camera adapter (see below) |
CONNECTING TO AN iOS DEVICE
Recent-generation Apple iOS devices have two types of connectors: Lightning or USB-C.
For iOS devices with a USB-C port, simply connect the M Series interface directly to the iOS device with a standard USB-C-to-C cable (sold separately).
For iOS devices with a Lightning port, the following is required (to supply enough power):
■ Powered USB hub
■ Apple Lightning to USB3 Camera Adapter

text_image
Powered USB hub AC power USB power adapter iOS deviceFigure 3-4: The Apple Lightning to USB3 Camera Adapter.
Connect the M Series interface to a USB port on the powered USB hub. Connect the powered USB hub host port to the camera adapter with a USB cable. Connect the camera adapter Lightning port to the iOS device Lightning port, as shown in Figure 3-4.
AUDIO CONNECTIONS
Here are a few things to keep in mind as you are making audio connections to your M Series interface.
Mic/line/instrument inputs with preamps
Connect a microphone, guitar or line-level analog input to the XLR/quarter-inch combo jacks with either a standard mic cable or a balanced cable with a quarter-inch plug.
Do not connect a +4 (line level) XLR cable to the inputs (because of the preamps). Use a quarter-inch input instead.
Phantom power
If you are connecting a condenser microphone or another device that requires phantom power, engage the corresponding 48V phantom power switch.
Preamp gain
The M series preamps provides 60 dB of gain. Use the front panel trim knobs to adjust gain as needed for each input. Watch the input level meter in the
LCD while adjusting gain. Try to adjust gain as high as possible without clipping, which is indicated by the red rectangle at the top of the meter.
Combo jack summary
Use these guidelines for 48V phantom power and trim settings on the two combo input jacks:
| Input | 48V Trim |
| Condenser mic On As needed | |
| Dynamic mic Off As needed | |
| Guitar Off As needed | |
| Line level Off Zero | |
TRS quarter-inch analog inputs and outputs
Quarter-inch analog inputs and outputs are balanced (TRS) connectors that can also accept an unbalanced plug. The outputs are DC-coupled, so they can be used for CV control output.
Quarter-inch analog outputs are not cross-coupled. Therefore, when connecting them to an unbalanced input, use a TRS plug with the ring disconnected. Not floating the negative terminal will short it to the sleeve ground and cause distortion.
Unbalanced RCA outputs (M2 and M4 only)
Connect the unbalanced RCA outputs to other gear that has similar unbalanced RCA inputs, such as DJ systems, karaoke equipment or consumer audio devices.
Monitor outs
In a standard studio configuration, the monitor outs are intended for a pair of primary studio monitors, but they can be used as regular outputs for any purpose.
A/B monitor switching on the M6
If you have an M6 and two different sets of studio monitors, and you would like to be able to switch between them to compare how your mixes sound on each pair, connect your primary monitors (A) to the MONITOR 1-2 outputs and connect the secondary monitor pair (B) to LINE OUT 1-2. Then press and hold the A/B switch on the front panel. Doing so engages A/B mode. In this mode, you can then quickly press the A/B button to switch between the A speakers and B speakers. More specifically, in A/B mode, LINE OUT 1-2 no longer function as independent outputs. Instead, they mirror the signal on the MONITOR 1-2 outputs, and the A/B switch controls which pair plays (while the other is muted).
To exit A/B mode, press and hold the A/B switch.
Headphones
Connect your headphones to the headphone output on the front panel. The headphone output mirrors the signal on the MONITOR 1-2 outputs. Use the volume knob above it to control its volume independently. The M6 has two headphone outputs. Both mirror the signal on the MONITOR 1-2 outputs and have their own independent volume control. One of the headphone outputs has a 3-4 switch. When engaged, the output mirrors the signal on LINE OUT 3-4 instead. This allows you to set up a separate headphone mix from your host software (on outputs 3-4).
MIDI CONNECTIONS
Connect your MIDI device's MIDI IN jack to the M series MIDI OUT jack (Connection A below). Conversely, connect the MIDI device's MIDI OUT jack to the M Series MIDI IN jack (Connection B).

flowchart
graph TD
A["MIDI OUT"] -->|MIDI cable| B["MIDI IN"]
C["MIDI OUT"] -->|MIDI cable| D["MIDI IN"]
E["MIDI IN"] -->|MIDI cable| F["MIDI OUT"]
G["MIDI IN"] -->|MIDI cable| H["MIDI IN"]
I["MIDI Device"] --> J["Keyboard"]
style A fill:#f9f,stroke:#333
style C fill:#f9f,stroke:#333
style E fill:#f9f,stroke:#333
style G fill:#f9f,stroke:#333
style I fill:#ccf,stroke:#333
Figure 3-5: Connecting a MIDI device to an M Series interface.
One-way MIDI connections
MIDI devices that do not receive MIDI data, such as a dedicated keyboard controller, guitar controller, or drum pad, only need Connection B shown in Figure 3-5. Similarly, devices that never send data, such as a sound module, only need Connection A. Make both connections for any device that needs to both send and receive MIDI data.
Connecting additional gear with MIDI THRUs
If you need to connect several pieces of MIDI gear, run a MIDI cable from the MIDI THRU of a device already connected to the M Series interface to the MIDI IN on the additional device as shown below in Figure 3-6. The two devices then share the M Series MIDI OUT port. This means that they share the same set of 16 MIDI channels, too, so try to do this with devices that listen to only one MIDI channel (such as effects modules), which makes it easier to avoid MIDI channel conflicts.

flowchart
graph TD
A["MIDI Series rear panel"] -->|MIDI OUT| B["MIDI Device"]
B -->|MIDI THRU| C["MIDI cable"]
C --> D["MIDI IN"]
Figure 3-6: Connecting additional devices with MIDI THRU ports.
CHAPTER 4 Working with Host Audio Software
OVERVIEW
M Series interfaces provide multi-channel audio input and output for Core Audio compatible audio applications on the Mac and ASIO compatible applications on Windows, including MOTU's Performer Lite and Digital Performer, Apple's Logic Pro and GarageBand, and other third-party software applications such as Ableton Live, Avid Pro Tools, Cockos Reaper, Propellerhead Reason, Steinberg Cubase and Nuendo, PreSonus Studio One, Bitwig, and others.
Performer Lite and Ableton Live Lite are both available as a free download for M Series owners at motu.com. Just log in to your account and go to your Product Registrations tab. For complete information about all of Performer Lite's powerful workstation features, refer to the Performer Lite User Guide.pdf found in the Help menu of the Performer Lite application.
Digital Performer, MOTU's state-of-the-art digital audio workstation software, is available separately; for details about upgrading from Performer Lite to Digital Performer, talk to your authorized MOTU dealer or visit motu.com.
Preparation....21
Choosing the M Series driver....21
Reducing monitoring latency....22
Loopback....23
PREPARATION
Install your host audio software first if you haven't already done so, and complete these chapters before proceeding:
■ chapter 2, "Software Installation" (page 11)
■ chapter 3, "Hardware Installation" (page 15)
CHOOSING THE M SERIES DRIVER
For macOS audio software
For macOS, go to the Sound control panel and choose the M2, M4 or M6 for input and output. If you've installed the M series driver for macOS, go to the menu item or preference in your host audio software where you choose the audio device (Core Audio driver) you wish to use, and then select the M2, M4 or M6 by name (see Figure 2-1 on page 12).

text_image
Sound Sound Effects Output Input Select a device for sound output: Name Type Display Audio USB M4 USB MacBook Pro Speakers Built-in Settings for the selected device: The selected device has no output controlsFor Windows audio software
For audio software running under Windows, go to the menu item or preference where you choose the ASIO driver you wish to use, and then choose MOTU M Series.

text_image
Configure Hardware Driver ASIO ASIO Driven: MOTUN Series Sample Rate: 48000 Clock Source: Internal Configure Driver Overnide internal buffer size: 256 Priority Boost Cancel OKFigure 4-1: Choosing the M Series ASIO driver in Performer Lite on Windows (Setup menu > Configure Audio System > Configure Hardware Driver).
Where to go in popular audio hosts
Here is the location for this setting in various popular audio software host applications:
| Host software | Location for choosing the M series interface |
| Digital Performer and Performer Lite | Setup menu > Configure Audio System > Configure Hardware Driver |
| Pro Tools 9 or later Setup menu > Playback Engine or Current Engine | |
| Logic Pro Preferences > Audio tab > Devices tab > Core Audio tab | |
| Garage Band Garage Band menu > Preferences > Audio/MIDI > Audio Output/Input menus | |
| Cubase and Nuendo Device Setup > Devices list > VST Audio System menu | |
| Live Preferences > Audio tab | |
| Reason Preferences > Audio preferences | |
| Reaper Preferences > Audio prefs > Devices | |
Other audio software
Consult your software's manual for further information.
REDUCING MONITORING LATENCY
Monitoring latency is a slight delay caused by running an input signal through your host audio software and back out. For example, you might hear it when you drive a live guitar input signal through an amp modeling plug-in running in your audio sequencer.
This delay is caused by the amount of time it takes for audio to make the entire round trip through your computer, from when it first enters an input on the M Series interface, passes through the interface hardware into the computer, through your host audio software, and then back out to an output.
Monitoring through the M series interface
If you don't need to process a live input with plug-ins, the easiest way to avoid monitoring latency is to disable your DAW's live monitoring feature and instead engage the MON (monitor) switch on the front panel of your M Series interface. Visit motu.com/m2-start (or /m4-start or /m6-start) to watch a video about this feature.
Monitoring through your host audio software
If you do need to process a live input with host software plug-ins, or if you are playing virtual instruments live through your MOTU audio hardware, you can significantly reduce latency by adjusting the audio buffer setting in your host audio software, as explained in the next section.
It is important to note that monitoring delay has no effect on the recording, or playback, of audio data from disk. The actual recording and playback is extremely precise, it is only the monitoring of your live input signal which may be delayed.
Adjusting your host software audio buffer
Buffers are small bundles of audio data. Your M Series interface “speaks” to your computer in buffers, rather than one sample at a time. The size of these buffers determine how much delay you hear when monitoring live inputs through your audio software: larger buffers produce more delay; smaller buffers produce less.
Adjusting buffer size on macOS
Under macOS, audio I/O buffer size is handled by the host audio application (not by the M Series Core Audio driver). Most audio software applications provide an adjustable audio buffer setting that lets you control the amount of delay you'll hear when monitoring live inputs or processing them with software plug-ins, as shown for Performer Lite in Figure 4-2.

text_image
Configure Hardware Driver CoreAudio Display Audio M2 MacBook Pro Microphone MacBook Pro Speakers Master Device: M2 Sample Rate: 48000 Clock Modes: M2 MDTU Internal Clock Buffer Size: 256 Work Priority: High Cancel OKFigure 4-2: In Digital Performer and Performer Lite, choose Setup menu> Configure Audio System> Configure Hardware Driver to open the dialog shown above and access the Buffer Size setting.
Adjusting buffer size on Windows
On Windows, the buffer size is adjusted in the M Series control panel (page 12). Also see "Buffer Size".
Lower latency versus higher CPU overhead
Buffer size has a large impact on the following:
■ Monitoring latency
■ The load on your computer's CPU
■ Responsiveness of transport controls and effect knobs in Performer Lite or other audio software.
■ Real-time virtual instrument latency.
The buffer setting presents you with a trade-off between the processing power of your computer and the delay of live audio as it is being patched through your software. If you reduce the size, you reduce monitoring latency, but significantly increase the overall processing load on your computer, leaving less CPU bandwidth for things like real-time effects processing. On the other hand, if you increase the buffer size, you reduce the load on your computer, freeing up bandwidth for effects, mixing and other real-time operations. If you are at a point in your recording project where you are not currently working with live, patched-thru material (e.g. you're not recording vocals), or if you have a way of externally processing inputs, choose a higher buffer size. Depending on your computer's CPU speed, you might find that settings in the middle work best (256 to 1024).
Transport responsiveness
Buffer size also impacts how quickly your audio software will respond when you begin playback, although not by amounts that are very noticeable. Lowering the buffer size will make your software respond faster; raising the buffer size will make it a little bit slower.
Effects processing and automated mixing
Reducing latency with the buffer size setting has another benefit: it lets you route live inputs through the real-time effects processing and mix automation of your audio software.
LOOPBACK
Use the Loopback 1-2 input channels provided by the M Series audio driver to capture audio output from your computer. These channels return the signal being sent to Outputs 1-2 back to the computer, as Loopback inputs 1-2, so that you can capture the signal in your host software, stream it to the web or broadcast it with pod casting software.
Mixing loopback with live inputs
If you need to mix loopback channels with live inputs, use the Loopback 1-2 Mix channels provided by the M Series audio driver. These channels combine audio being sent to Outputs 1-2 from the computer with any live signals on the unit's inputs. For example, you could play back a music (or other audio) from your computer software, speak or sing into a mic connected to the
M series unit, and feed the combined result back to the computer for recording or internet streaming.
Remember, be careful! When monitoring loopback channels and live inputs, your host software can cause loud feedback loops. Be sure to disable the monitoring of loopback tracks to avoid feedback.
APPENDIX A
Troubleshooting
Problem Solution Applies to
| I don’t hear any sound from my M Series interface | Is the M Series selected as the default device for input and output for your computer and/or host audio software? | All |
| Is the INPUT/PLAYBACK knobM4 / M6 set to the center position? | ||
| Is the Phones knob and/or Monitor knob turned up? | All | |
| (macOS Users) Does your host audio software require Microphone Access in System Preferences > Security and Privacy? | All | |
| How do I monitor in stereo (or mono) | Press and hold the MON button to enable/disable stereo monitoring mode. | All |
| Loopback inputs don’t appear in my macOS host software | Install the optional M Series driver. Some DAWs will not show the Loopback channel names by default. Go to the link below to see the assigned I/O numbers to use for loopback:https://motu.com/techsupport/technotes/channellisting | All |
| I don’t hear any audio on the phones output with the 3-4 switch | Is 3-4 engaged? This mirrors output channels 3-4 (Line Out), rather than 1-2 (Monitor Out). | M6 |
| “Low USB Power” The M6 must be connected to the DC power adapter when the M6 is connected to a host computer with a USB Type A port (instead of a USB Type C port). See “Power” on page 18. | M6 | |
My MOTU interface isn't showing up in Audio MIDI Setup on my Mac.
Due to the updated architecture of the new macOS High Sierra (10.13) or higher, the system extensions for all newly-installed third-party software will automatically be blocked from running. If your MOTU interface is not showing up in Audio MIDI Setup or your DAW on High Sierra or higher, you might need to enable the driver in your System Preferences. To do so, first download and install the very latest installer for your MOTU M Series interface. After restarting,
open System Preferences. Select Security & Privacy. In the General section, click the Allow button. The Allow button will disappear 30 minutes after installation. To display the Allow button, run the installer for the MOTU driver again.
How do I monitor live inputs?
Please refer to the documentation for the audio application that you are using. If your application does not support input monitoring, you will need to use the hardware monitoring feature in your M Series interface. Please see “Monitoring through the M series interface” on page 22.
How do I control monitoring latency?
See "Reducing monitoring latency" on page 22.
Connecting or powering gear during operation...
It is not recommended that you connect/disconnect, or power on/off devices connected to the M Series interface while recording or playing back audio. Doing so may cause a brief glitch in the audio.
CUSTOMER SUPPORT
We are happy to provide complimentary customer support to our registered users. If you haven't already done so, please take a moment to register online at MOTU.com, or fill out and mail the included registration card. Doing so entitles you to technical support and notices about new products and software updates.
TECHNICAL SUPPORT
If you are unable, with your dealer's help, to solve problems you encounter with your MOTU device, you may contact our technical support department in one of the following ways at motu.com/support:
■ Live Chat: You can connect directly with a technician Monday through Friday between 10 AM and 5 PM Eastern Time.
■ Schedule a call: You can schedule a callback time to speak with a technician by phone Monday through Friday between 1 PM - 5 PM Eastern time.
■ Support ticket: You can submit an online support ticket (TechLink) at any time, 24 hours a day, 7 days a week. A technician will get back to you in 1-2 business days.
Please provide the following information to help us solve your problem as quickly as possible:
■ The serial number of your MOTU device. This is printed on a label placed on the bottom of the unit and on the side of the box. You must be able to supply this number to receive technical support.
■ A brief explanation of the problem, including the exact sequence of actions which cause it, and the contents of any error messages which appear on the screen.
■ The pages in the manual that refer to the features or operation of your MOTU Device or Performer Lite with which you are having trouble.
- The version of your computer's operating system.
We're not able to solve every problem immediately, but a quick TechLink or chat may yield a suggestion for a problem which you might otherwise spend hours trying to track down.
If you have features or ideas you would like to see implemented, we'd like to hear from you. Please write to the Development Team, MOTU Inc., 1280 Massachusetts Avenue, Cambridge, MA 02138, or use our online suggestion box at www.motu.com/suggestions.
APPENDIX B Audio Specifications
MIC in
| Connector Type Combo-style, XLR / TRS Pin 2 hot, tip hot |
XLR
| Impedance load 2.65 k Ω |
| Phantom power +48 v, switchable per channel DIN 45596 / IEC 61938-P48 |
| EIN -129 dBu At maximum gain, 150Ω, A-weighted |
| Dynamic Range 115 dB @ 10dBu (-97dB), A-weighted |
| THD+N -97 dB (< 0.0014%) Unweighted |
| Frequency Response +0 -0.1 dB, 20 Hz/20 kHz Ref. 1 kHz |
| Max Level In | +10 dBu | At minimum gain |
| Gain range | 0 to +60 dB |
TRS
| Description | Balanced or single ended | Suitable for line or instrument (guitar) |
| Impedance Load | 1 meg Ω2 meg Ω | Single-ended (instrument)Differential (balanced) |
| Phantom power | No |
| Dynamic Range 114 dB A-weighted |
| THD+N -100 dB < 0.0010% | @ 14dBu (-96dB) |
| Frequency Response 20 Hz - 20 kHz ± 0.15dB |
| Max Level in | +16 dBu | At minimum gain |
| Gain range | 0 to +57 dB |
Line In (M4 and M6 only)
| Description | Balanced or single ended Suitable for line input only |
| Phantom power | No |
| Dynamic Range 115 dB A-weighted |
| THD+N -106 dB < 0.0005% | @ 18dBu |
| Frequency Response 20 Hz - 20 kHz ± 0.07dB |
| Max Level in | +18 dBu | At minimum gain |
Line Out
| Connector Type 1/4” Female, TRS Balanced, tip hot |
| Output Impedance 100 ohm Per leg |
| Dynamic Range 120 dB A-weighted |
| THD+N -110 dB < 0.00032% @ -1 dBFS, Unweighted, 1 kHz |
| Frequency Response +0, -0.1 dB, 20 Hz/20 kHz Ref. 1 kHz |
| Max Level Out +16 dBu |
| Maximum output voltage 3.6V |
RCA Out (M2 and M4 only)
| Connector Type Female RCA |
| Dynamic Range 119 dB A-weighted |
| THD + N - 105 dB < 0.00056% @ 9.5dBu |
| Max Level Out +9.5 dBu |
Phones
| Connector Type 1/4” Female, TRS Stereo | Tip Left, Ring Right |
| Dynamic Range | 115 dB A-Weighted |
| THD+N -110 dB < 0.0003% @ -1dBFS | |
| Max Output Level | +12.5 dBu |
| Trim Range | 128 dB 0 to -128 dB (muted) |
+4dB analog input 19
-10dB analog input 19
8pre-es
specifications 27
A
A/B switch9,19
Ableton Live 21,22
Analog inputs/outputs making connections to 19
Apple
GarageBand 22
iOS connection 18
Logic Pro 22
ASIO 12
ASIO driver 21
Audio
MIDI Setup utility 13
Avid
Pro Tools 22
B
Balanced analog 19
Buffer Size 12
C
Class compliance 11
Cockos Reaper22
Condenser mic input19
Control Panel 12
Controller
connecting20
Core Audio driver 21
Core MIDI
Audio MIDI Setup 13
benefits 13
Cubase 21, 22
Customer
support 25
D
Digital Performer 21, 22
Driver installation 11
Drivers
installing USB drivers 11
Dynamic mic 19
G
GarageBand 21, 22
Guitar
connecting19
H
Headphone outputs 7,8,9
Headphones
connecting16
Host
Buffer Size 12
1
Installation
QuickStart Guide5
software 11
iOS
connection 18
operation 11
iPad/iPhone
connection 18
support 11
K
Keyboard controller
connecting 20
L
Latency12, 22, 23
Lightning connection to iOS 18
Live 22
Logic Pro 22
Logic Pro/Express21
Loopback23
M
M Series
Control Panel 12
M4
setup example 16
Mac
USB connection 18
MacOS 21
system requirements 10
Main outs
front panel volume control19
making connections to 19
Mic/guitar inputs 18
MIDI
software setup 13
Windows driver installation 13
Monitoring
thru main outs 19
MOTU
AVB Installer11
Digital Performer 22
Performer Lite 12, 22, 23
Pro Audio ASIO driver21
N
Nuendo 21, 22
0
Optimization 23
P
Patch thru
latency 23
PC
USB connection 18
Performance 23
Performer Lite 12, 21, 22, 23
Phantom power 18, 19
Phone outputs 7,8,9
Power switch 7,8,9
Pro Tools 21, 22
Q
QuickStart Guide5
R
Reaper 21, 22
Reason21
Propellerhead Reason 22
Registration 10
S
Sample Rate
Windows operation 12
Software
installation 11
Software installer 11
Sound module
connecting 20
Stage monitors
connecting 16
Steinberg
Cubase 22
Nuendo 22
Studio setup (example) 16
Sync Windows sample rate 13
Synths
connecting 16
System requirements
minimum 10
recommended computer 10
T
Technical support 25
Trim 18
TRS connectors 19
U
Unbalanced analog 19
USB
class compliance 11
connection 18
installing drivers 11
Use lowest latency safety offsets 3
W
Windows
system requirements 10