M ONE X - Receiver Helix - Free user manual and instructions

Product Type	Mono Subwoofer Amplifier
Brand	Helix
Model	M ONE X
Amplifier Technology	Class D
RMS Output Power (1% THD+N)	1 x 400 W @ 4 Ohm, 1 x 700 W @ 2 Ohm, 1 x 1030 W @ 1 Ohm
TwinPower Link RMS Power (2 amplifiers)	1 x 1400 W @ 4 Ohm, 1 x 2060 W @ 2 Ohm
Frequency Response	10 Hz - 250 Hz
Lowpass Filter	50 Hz - 250 Hz adjustable
Subsonic Filter	10 Hz - 50 Hz adjustable
Bandpass	10 Hz - 250 Hz adjustable (combination of subsonic and lowpass)
Bass Boost	0 - 12 dB @ 30 - 80 Hz, Q-factor adjustable (NAR/WIDE)
Phase Adjustment	0° - 180°
Inputs	2 x RCA/Cinch (low-level), 2 x High-Level speaker input (ADEP), 1 x Remote In, 1 x Remote Control Input
Input Sensitivity	RCA/Cinch: 0.5 - 6 V, High-Level: 1.1 - 13 V
Speaker Output	1 x speaker output, min. load 1 Ohm (2 Ohm in TwinPower Link)
Power Supply	10.5 - 16 V DC (max. 5 sec down to 6 V), idle current 800 mA
Fuse Rating	3 x 40 A Maxi-fuse (APX)
Signal-to-Noise Ratio	95 dB (A-weighted)
Distortion (THD)	0.20%
Damping Factor	150
Dimensions (H x W x D)	50 x 320 x 154 mm / 2.00 x 12.6 x 6.06 in
Weight	Not specified in manual (approx. 2.5 kg)
Additional Features	ADEP (Advanced Diagnostics Error Protection), Start-Stop capability, automatic turn-on via high-level input, TwinPower Link bridge mode, included cable remote control
Protections	Overheating, over/undervoltage, short-circuit on speakers, false connection; indicated by red Protect LED
Recommended Installation	Dry location with air circulation, secure mounting, use proper gauge wires (min. 10 mm² / AWG 8 for power/ground)
Warranty	Complies with legal regulations; damage from overload or improper use not covered

Frequently Asked Questions - M ONE X Helix

What is the minimum speaker impedance for the Helix M ONE X?

The minimum load impedance is 1 Ohm for normal operation. In TwinPower Link mode (two amplifiers bridged), the minimum impedance is 2 Ohms.

How do I connect the high-level speaker inputs?

Use the included pluggable screw-terminal. Connect the speaker outputs of the OEM/aftermarket radio to the Highlevel Input terminals, ensuring correct polarity. The amplifier will automatically turn on when a speaker signal is detected, so the REM connection is not required.

Can I use both low-level and high-level inputs simultaneously?

No, it is strictly forbidden to use both the Lowlevel Line Input and Highlevel Input at the same time. Doing so may cause severe damage to the low-level outputs of your head unit.

How do I set the gain properly?

The Gain control adjusts input sensitivity (0.5-6V for RCA, 1.1-13V for high-level). It is not a volume control. For standard car radios using high-level input, set the gain to approximately 9V (turn from max CCW to 9 o'clock). Proper adjustment prevents distortion and damage.

What does the Power/Protect LED indicate?

Green means the amplifier is ready for operation. Red indicates a malfunction, such as overheating, over/undervoltage, short-circuit on speakers, or false connection. Check for wiring errors or incorrect adjustments. If the amp does not turn on, it may be defective.

How do I use TwinPower Link to bridge two M ONE X amplifiers?

Set one amplifier as 'Master' and the other as 'Slave' using the TwinPower Link switch. Connect the Mono RCA/Cinch output of the Master to the input of the Slave. The Master controls all filter and boost settings for both amps. Minimum load impedance becomes 2 Ohms.

What is the ADEP circuit?

ADEP stands for Advanced Diagnostics Error Protection. It prevents error logs and feature loss (e.g., fader) in modern OEM radios when using high-level inputs. It also avoids overloading the radio's speaker outputs at high volumes.

What wire gauge is recommended for power and ground connections?

For short runs (under 1m), use at least 10 mm² / AWG 8. For longer runs, use 16-25 mm² / AWG 6-4. The ground wire should be the same gauge as the power wire.

How do I adjust the subsonic and lowpass filters?

The Subsonic control (10-50 Hz) cuts very low frequencies to relieve the amplifier and subwoofer. The Lowpass control (50-250 Hz) sets the upper cutoff. Together they create a bandpass. Ensure the crossover frequencies are at least two octaves apart (e.g., lowpass 100 Hz, subsonic 25 Hz or less).

What should I do if the amplifier goes into protection mode (red LED)?

First, turn off the system and check for short circuits on speaker wires, correct impedance (not below 1 Ohm), proper power and ground connections, and adequate cooling. Also check for over/undervoltage. If the issue persists, consult an authorized HELIX dealer.

USER MANUAL M ONE X Helix

⑥ Mono Cinch In- / Output

⑧ Bass Boost Q-Factor

⑥ Mono Cinch In- / Output

⑧ Bass Boost Q-Factor

⑨ Bass Boost Frequenz

Mono

Congratulations on your purchase of this innovative and high-qual ity HELIX product.

The HELIX M ONE X highlights best quality, excellent manufacturing and state-of-the-art technology. Thanks to more than 30 years of experience in research and development of audio products this amplifier generation sets new standards.

We wish you many hours of enjoyment with your new HELIX amplifier.

Yours,

AUDIOTEC FISCHER Team

General instructions

General installation instructions for HELIX components

To prevent damage to the unit and possible injury, read this manual carefully and follow all installation instructions. This product has been checked for proper function prior to shipping and is guaranteed against manufacturing defects.

Before starting your installation, disconnect the battery's negative terminal to prevent damage to the unit, fire and/or risk of injury. For a proper performance and to ensure full warranty coverage, we strongly recommend to get this product installed by an authorized HELIX dealer.

Install your M ONE X in a dry location with sufficient air circulation for proper cooling of the equipment. The amplifier should be secured to a solid mounting surface using proper mounting hardware. Before mounting, carefully examine the area around and behind the proposed installation location to ensure that there are no electrical cables or components, hydraulic brake lines or any part of the fuel tank located behind the mounting surface. Failure to do so may result in unpredictable damage to these components and possible costly repairs to the vehicle.

General instruction for connecting the HELIX M ONE X amplifier

The HELIX M ONE X amplifier may only be installed in vehicles which have a 12 Volts negative terminal connected to the chassis ground. Any other system could cause damage to the amplifier and the electrical system of the vehicle.

The positive cable from the battery for the complete system should be provided with a main fuse at a distance of max. 30 cm from the battery. The value of the fuse is calculated from the maximum total current input of the car audio system.

Use only suitable cables with sufficient cable cross-section for the connection of the HELIX M ONE X. The fuses may only be replaced by identically rated fuses (3 x 40 A) to avoid damage of the amplifier.

Prior to installation, plan the wire routing to avoid any possible damage to the wire harness. All cabling should be protected against possible crushing or pinching hazards. Also avoid routing cables close to potential noise sources such as electric motors, high power accessories and other vehicle harnesses.

1 Line Input

RCA inputs for connecting lowlevel line signals.

② Highlevel Input

Highlevel speaker inputs for connecting a factory radio or an aftermarket radio without lowlevel line outputs.

③ Gain

Control for adjusting the input sensitivity of the lowlevel Line and Highlevel Inputs.

④ Phase

Control for adjusting the phase from 0^ to 180^ .

⑤ TwinPower Link switch

Switch for operating two M ONE X amplifiers in bridge mode.

⑥ Mono RCA/Cinch In- / Output

Mono RCA/Cinch signal in- or output for bridge mode operation in TwinPower Link mode.

⑦ Bass Boost Gain

Control for adjusting the bass boost from 0 to 12 dB.

⑧ Bass Boost Q-Factor

Control for adjusting the Q factor (bandwidth) of the Bass Boost

⑨ Bass Boost Frequency

Control for adjusting the center frequency of the Bass Boost from 30 to 80 Hz.

10 Subsonic

Control for adjusting the subsonic filter from 10 to 50 Hz.

11 Lowpass

Control for adjusting the lowpass filter from 50 to 250 Hz.

12 Remote

Input for connecting the included cable remote control for volume adjustment.

13 Speaker Output

Speaker outputs for connecting subwoofers.

14 Power & Protect LED

This LED indicates the operating mode of the amplifier.

15 Fuse

Input fuses - 3 x 40 Ampere.

⑯ +12 V

Connector for the +12 V power cable of the positive terminal of the battery.

17 REM

Connector for the remote cable.

18 GND

Connector for the ground cable (negative terminal of the battery or metal body of the vehicle).

Initial start-up and functions

① Line Input

2-channel lowlevel line input to connect signal sourc es such as head units / radios / DSPs.

Important: It is strictly forbidden to use the High-level Input and lowlevel Line Input at the same time. This may cause severe damage to the lowlevel line outputs of your head unit / car radio.

② Highlevel Input

2-channel highlevel loudspeaker input to connect the amplifier directly to the loudspeaker outputs of OEM / aftermarket radios that do not have any low-level line outputs.

The Highlevel Input is equipped with our proprietary ADEP circuit (Advanced Diagnostics Error Protection) which ensures that the car radio detects the amplifier as a speaker and thus neither any function of the radio (e.g. fader) will be deactivated nor any error log in the CPU of the car will be created. If this input is used the remote input (REM) does not need to be connected as the amplifier will automatically turn on once a loudspeaker signal is applied.

Attention: Solely use the pluggable screw-terminal for the highlevel connector which is included in delivery!

Important: It is strictly forbidden to use the High-level Input and lowlevel Line Input at the same time. This may cause severe damage to the lowlevel line outputs of your car radio.

③ Gain

This control is used to adapt the input sensitivity to the output voltage of the connected signal source. This is not a volume control, it's only for adjusting the amplifier gain. The control range of the RCA / Line Input (lowlevel) is 0.5 - 6 Volts and 1.1 - 13 Volts for the Highlevel Input.

If the Highlevel Input is used in combination with a standard car radio we recommend an input sensitivity of roughly 9 Volts. For this purpose, turn the control from max. CCW position to 9 o'clock position.

④ Phase Shift

This control is used to adjust the phase from 0^ to 180^ . This allows to match the phase of the subwoofer with the other speakers thus avoiding any cancellations in the frequency response due to phase shifts.

⑤ TwinPower Link switch

The HELIX M ONE X amplifier can be connected to a second M ONE X via the TwinPower Link by which the output power is more than doubled, depending on the speaker configuration. In order to operate two amplifiers in this mode, they must be connected with a RCA / Cinch cable (see item 6; Mono RCA/Cinch In- / Output). The amplifier which is set as "Master" assumes the complete control (active crossover, bass boost etc.) for both amps. All filter adjustments of the amplifier which operates in "Slave" mode will be deactivated.

Attention: Make sure that one amplifier is adjusted as "Master" and the other one as "Slave". In this mode the minimum speaker impedance is 2 Ohms. Note: If the amplifier operates individually the TwinPower Link switch must be set to "Master". Examples for speaker configurations in TwinPower Link mode can be found on page 22.

⑥ Mono RCA/Cinch In- / Output

This connector serves as signal in- or -output for connecting a further M ONE X amplifier in bridge mode (see item 5; TwinPower Link switch).

⑦ Bass Boost Gain

This control is used to increase the adjusted bass center frequency (see item 9) from 0 to 12 dB.

Initial start-up and functions

⑧ Q-Factor

This control is used to adjust the Q factor (bandwidth) of the Bass Boost. When set to “NAR” only a narrow range around the center frequency (defined by control 9) will be affected whereas when set to “WIDE” the Bass Boost has a broadband effect around the chosen center frequency. The Q factor remains constant if the centre frequency (control 9) is changed

⑨ Bass Boost Frequency

This control is used to adjust the center frequency of the Bass Boost from 30 Hz to 80 Hz. The adjusted bass frequency can be enhanced from 0 to 12 dB with control 7.

This is useful to emphasize or correct a determined frequency of the subwoofer (kickbass).

⑩ Subsonic

This control is used to adjust the crossover frequency of the subsonic filter from 10 Hz to 50 Hz. The subsonic filter cuts off very low frequencies which aren't audible and therefore relieves the amplifier and also the subwoofer. Additionally the amplifier will have more power available for the audible frequencies. This control is always activated and its adjustment is mandatory.

⑪ Lowpass

This control is used to adjust the crossover frequency of the lowpass filter from 50 Hz to 250 Hz. This control is always activated and its adjustment is mandatory.

In combination with the subsonic filter, the lowpass filter creates a bandpass in any case. By adjusting the subsonic (control 10) and lowpass filter (control 11) any bandpass between 10 Hz and 250 Hz can be realized.

Caution: To avoid a loss of gain make sure that the crossover frequencies of the subsonic and lowpass filters do have an interval of at least two octaves when generating a bandpass. That means if the lowpass is adjusted to 100 Hz the subsonic should be adjusted to 25 Hz or less (one octave = doubled frequency or halved frequency).

12 Remote

This input is used to connect the included cable remote control. The remote control allows you to control the volume of the connected subwoofer.

13 Speaker Output

Speaker outputs to connect a subwoofer. The minimum load impedance must not be lower than 1 Ohm.

14 Power & Protect LED

The power and protect LED indicates the operating mode of the amplifier.

Green: The amplifier is ready for operation.

Red: A malfunction has occurred. A malfunction may have different causes as the HELIX M ONE X is equipped with several protection circuits. These protections shut off the amplifier in case of overheating, over- and undervoltage, short-circuit on loudspeakers and false connection.

Please check for connecting failures such as short-circuits, wrong connections, wrong adjustments and over temperature.

If the amplifier does not turn on it is defective and has to be sent to your local authorized dealer for repair service. A detailed description of the malfunction and the purchase receipt has to be attached.

15 Fuse

The input fuses are connected in parallel and provide protection against an internal fault of the device, therefore the system must be additionally protected by a further main fuse located close to the battery (max. distance from battery: 30 cm / 12"). The HELIX M ONE X is equipped with 3 x 40 Ampere fuses.

⑯ +12 V

Connect the +12 V power cable to the positive terminal of the battery. Recommended cross section: min. 10 mm ^4 / AWG 8.

17 REM

The remote lead should be connected to the remote output / automatic antenna (aerial positive) output of the head unit / car radio. This is only activated if the head unit is switched on. Thus the amplifier is switched on and off together with the head unit / car radio. This input needn't to be assigned if the Highlevel Input is used.

18 GND

The ground cable should be connected to a common ground reference point (this is located where the negative terminal of the battery is grounded to the metal body of the vehicle) or to a prepared metal location on the vehicle chassis i.e. an area which has been cleaned of all paint residues. Recommended cross section: min. 10 mm ^2 / AWG 8.

Connection of HELIX M ONE X to the head unit / car radio:

Caution: Carrying out the following steps will require special tools and technical knowledge. In order to avoid connection mistakes and / or damage, ask your dealer for assistance if you have any questions and follow all instructions in this manual (see page 11). It is recommended that this unit will be installed by an authorized HELIX dealer.

1. Connecting the lowlevel line inputs

Use the correct cable (RCA / Cinch cable) to connect these inputs to the lowlevel line outputs of your car radio. It is mandatory to use both lowlevel line inputs.

The automatic turn-on circuit does not work when using the lowlevel line inputs. In this case the remote input (REM) has to be connected to activate the HELIX M ONE X.

Important: It is strictly forbidden to use the Highlevel Input and lowlevel Line Input at the same time. This may cause severe damage to the lowlevel line outputs of your car radio.

2. Connecting the highlevel speaker inputs

The highlevel loudspeaker inputs can be connected directly to the loudspeaker outputs of an OEM or aftermarket radio using appropriate cables (loudspeaker cables with 1 mm^2 / AWG 18 max. ).

It is mandatory to use both highlevel speaker inputs. Make sure that the polarity is correct. If one connection has reversed polarity it may affect the performance of the amplifier. If this input is used the remote input (REM) does not need to be connected as the amplifier will automatically turn on once a loudspeaker signal is applied.

3. Adjustment of the input sensitivity

Attention: It is mandatory to properly adapt the input sensitivity of the M ONE X to the signal source in order to avoid damage to the amplifier.

If you want to change the input sensitivity use the Gain control (see page 15, item 3). The setting of the control affects both the lowlevel line inputs (LineInput) and the highlevel speaker inputs (Highlevel Input)!

If the HighlevelInput is used in combination with a standard car radio we recommend an input sensitivity of roughly 9 Volts. For this purpose, turn the control from max. CCW position to 9 o'clock position.

4. Connection to power supply

Make sure to disconnect the battery before installing the HELIX M ONE X!

Connect the +12 V power cable to the positive terminal of the battery. The positive wire from the battery to the amplifier power terminals needs to have an inline fuse at a distance of less than 12 inches (30 cm) from the battery. The value of the fuse is calculated from the maximum total current draw of the whole car audio system (M ONE X = max. 120 A RMS at 12 V power supply). If your power wires are short (less than 1 m / 40") then a wire gauge of 10 mm² / AWG 8 will be sufficient. In all other cases we strongly recommend gauges of 16 - 25 mm² / AWG 6 - 4!

The ground cable (same gauge as the +12 V wire) should be connected to a common ground reference point (this is located where the negative terminal of the battery is grounded to the metal body of the vehicle), or to a prepared metal location on the vehicle chassis, i.e. an area which has been cleaned of all paint residues.

5. Connecting the remote input

The remote input (REM) has to be connected to the radio remote output if the amplifiers low-level line inputs are used as signal inputs. We do not recommend controlling the remote input via the ignition switch to avoid pop noise during turn on/off.

If the Highlevel Input is used this input does not need to be connected as long as the car radio has BTL output stages.

6. Connecting the loudspeaker outputs

The loudspeaker outputs can be connected directly to the wires of the loudspeakers.

Never connect any of the loudspeaker cables to the chassis ground as this will damage your amplifier and your speakers.

If The positive terminal is indicated on most speakers. The minimum load impedance must not be lower than 1 Ohm, (2 Ohm in TwinPower Link operation) otherwise the amplifier protection will be activated. Examples for speaker configurations can be found on page 20 et sqq.

Unique Features of the HELIX M ONE X

Smart highlevel input

The latest generation of OE car radios incorporates sophisticated possibilities of diagnosing the connected speakers. If a common amplifier will be hooked up failure messages and loss of specific features (e.g. fader function) quite often appear – but not with the M ONE X.

The new ADEP circuit (Advanced Diagnostics Error Protection) avoids all these problems without loading the speaker outputs of the OE radio during high volumes unnecessarily.

Start-Stop capability

The switched power supply of the HELIX M ONE X assures operation even if the battery's voltage drops down to 6 Volts during engine crank.

Examples for speaker configurations

Mono

Subwoofer with one voice coil (single voice coil)

RMS output power ≤ 1% THD+N:

1 x 4 Ohms: 400 Watt

1 x 2 Ohms: 700 Watt

1 x 1 Ohm: 1,030 Watts

Parallel operation

Two subwoofers with one voice coil (single voice coil) or one subwoofer with dual voice coil are connected in parallel.

Note: The parallel connection of two voice coils will result in halving the impedance!

RMS output power ≤ 1% THD+N:

Two subwoofers with 1 x 4 Ohms correspond to a total impedance of 2 Ohms: 1 x 700 Watt

One subwoofer with 2 x 4 Ohms also corresponds to a total impedance of 2 Ohms: 1 x 700 Watt

Two subwoofers with 1 x 2 Ohms correspond to a total impedance of 1 Ohm: 1 x 1,030 Watt

One subwoofer with 2 x 2 Ohms also corresponds to a total impedance of 1 Ohm: 1 x 1,030 Watt

Note: The parallel connection of 1 Ohm voice coils will result in shutdown of the amplifier.

One subwoofer with a dual voice coil

In series

Two subwoofers with one voice coil (single voice coil) or one subwoofer with dual voice coil are connected in series.

Note: The connection of two voice coils in series will result in doubling the impedance!

RMS output power ≤ 1% THD+N:

Two subwoofers with 1 x 2 Ohms correspond to a total impedance of 4 Ohms: 1 x 400 Watt

One subwoofer with 2 x 2 Ohms also corresponds to a total impedance of 4 Ohms: 1 x 400 Watt

Two subwoofers with 1 x 1 Ohm correspond to a total impedance of 2 Ohms: 1 x 700 Watt

One subwoofer with 2 x 1 Ohm also corresponds to a total impedance of 2 Ohms: 1 x 700 Watt

Note: The negative terminal of the first voice coil has to be connected to the positive terminal of the second voice coil by using a speaker wire with the same gauge as the other speaker.

Example configurations for TwinPower Link operation

Amplifier connection in TwinPower Link operation
Master Slave

Speaker connection in TwinPower Link operation

Master Slave

One subwoofer with one voice coil

(single voice coil)

RMS output power ≤ 1% THD+N:

1 x 4 Ohms: 1,400 Watts

1 x 2 Ohms: 2,060 Watts

Note: The negative terminals of both amplifiers have to be connected by using a speaker wire. The size should be similar to the speaker wires which are used for the subwoofer connection.

Master Slave

One subwoofer with dual voice coil in mono operation

(dual voice coil)

RMS output power ≤ 1% THD+N:

2 x 4 Ohms: 800 Watts

2 x 2 Ohms: 1,400 Watts

2 x 1 Ohm: 2,060 Watts

Note: The negative terminals of both amplifiers have to be connected by using a speaker wire.

The negative terminal of the first voice coil has to be connected to the positive terminal of the second voice coil.

The gauge of the wires should be similar to the speaker wires which are used for the subwoofer connection.

Technical Data

RMS-Output power <= 1% THD+N Normal operation TwinPower Link (One Amplifier) (Two amplifiers)

- @ 4 Ohm....1 x 400 Watts 1 x 1,400 Watts

- @ 2 Ohm....1 x 700 Watts 1 x 2,060 Watts

- @ 1 Ohm....1 x 1,030 Watts -

Max. output power per channel*:.....Up to 1,180 Watts RMS @ 1 Ohm

Amplifier technology ....Class D

Inputs....2 x RCA / Cinch ....2 x Highlevel speaker input ....1 x Remote In ....1 x Remote control input

Input sensitivity....RCA / Cinch 0.5 - 6 Volts ....Highlevel 1.1 - 13 Volts

Input impedance RCA / Cinch ....20 kOhms

Input impedance highlevel....9 - 33 Ohms

Outputs....1 x Speaker output

Frequency response....10 Hz - 250 Hz

Bass boost....0 - 12 dB / 30 - 80 Hz

Lowpass 50 Hz - 250 Hz adjustable

Bandpass....10 Hz - 250 Hz adjustable

Subsonic....10 Hz - 50 Hz adjustable

Phase 0 - 180° adjustable

Slope subsonic / lowpass 12 / 24 dB/Oct.

Signal-to-noise ratio analog input....95 dB (A-weighted)

Distortion (THD)....0.20 %

Damping factor....150

Operating voltage 10.5 - 16 Volts (max. 5 sec. down to 6 Volts)

Idle current....800 mA

Fuse....3 x 40 A Maxi-fuse (APX)

Additional features....Active, adjustable crossover, bass boost, phase shift, Start-Stop capability, highlevel input with automatic turn on function and Advanced Diagnostics Error Protection (ADEP), bass volume cable remote control

Dimensions (H x W x D)....50 x 320 x 154 mm / 2.00 x 12,6" x 6.06"

* In typical applications as subwoofer amplifier

Warranty Disclaimer

The limited warranty comply with legal regulations. Failures or damages caused by overload or improper use are not covered by the warranty. Please return the defective product only with a valid proof of purchase and a detailed malfunction description. Technical specifications are subject to change!

Errors are reserved! For damages on the vehicle and the device, caused by handling errors of the device, we can't assume liability. These devices are certified for the use in vehicles within the European Community (EC).

AUDIOTEC

FISCHER