QT15S - Subwoofer Qtx - Free user manual and instructions

Product Type	Active Subwoofer
Brand	Qtx
Model	QT15S
Driver Size	15 inches
Amplifier Power	500 W RMS
Impedance	8 ohms
Frequency Response	30 Hz - 200 Hz
Sound Pressure Level	120 dB SPL
Dimensions (W x H x D)	480 x 430 x 530 mm
Weight	28 kg
Power Supply	AC 220 V, 50/60 Hz
Input Connectors	XLR, 1/4" Jack, RCA
Output Connectors	XLR Link
Controls	Volume, Crossover, Phase
Enclosure Material	MDF with vinyl finish
Cleaning Instructions	Wipe with a dry, soft cloth. Avoid solvents.
Safety Precautions	Do not expose to moisture. Use correct voltage. Ensure proper ventilation.
Spare Parts / Repairability	Contact Qtx support for spare parts. Repairs by qualified technicians only.
General Information	Designed for PA and live sound reinforcement. Rugged construction for portable use.

Frequently Asked Questions - QT15S Qtx

What is the power rating of the Qtx QT15S subwoofer?

The Qtx QT15S has an RMS power rating of 500 W, with a peak power handling of around 1000 W.

What type of enclosure does the QT15S have?

It features a ported enclosure design to enhance low-frequency output and efficiency.

How do I connect the QT15S to my audio system?

Use a balanced XLR or 1/4-inch TRS cable from your mixer or amplifier to the subwoofer's input. The subwoofer also has a link output for daisy-chaining additional units.

What is the frequency response of the QT15S?

The frequency response is 30 Hz to 200 Hz, making it suitable for deep bass reproduction in live sound applications.

Is the Qtx QT15S an active or passive subwoofer?

The QT15S is an active subwoofer, meaning it has a built-in amplifier, so no external amp is required.

Can I use the QT15S outdoors?

Yes, but it should be protected from rain and direct moisture. The enclosure is durable but not waterproof. Use a cover if necessary.

What are the dimensions and weight of the QT15S?

It measures approximately 480 x 430 x 530 mm (width x height x depth) and weighs about 28 kg.

How do I clean the Qtx QT15S?

Wipe the cabinet with a dry, soft cloth. Do not use abrasive cleaners or solvents. Keep the grille clean from dust.

What safety precautions should I follow?

Ensure the mains voltage matches the rating (220 V AC). Do not block ventilation slots. Avoid overloading the subwoofer to prevent damage.

Where can I find spare parts or get repairs?

Contact Qtx support or an authorized service center. Use only genuine parts as specified in the manual.

USER MANUAL QT15S Qtx

Order ref: QT15SA (170.751UK)

QT18SA (170.754UK)

User Manual

Version 1.1

Caution: Please read this manual carefully before operating

Damage caused by misuse is not covered by the warranty

Introduction

Thank you for choosing a QT-series active subwoofer as part of your sound system. This unit is designed to offer powerful sub frequencies for PA systems in leisure and entertainment applications.

Package Contents

Please check the contents to ensure that the product has been received in good condition with the appropriate mains lead(s). If you find that the product has arrived with any problems, please contact your retailer at once.

Warning

This product contains no user-serviceable parts so make no attempt to try to fix or modify this item yourself as this will invalidate the warranty. We recommend you keep the original package and proof of purchase for any possible replacement or returned demand. To prevent the risk of fire or electric shock, do not expose this appliance to rain or moisture. To prevent electric shock do not remove the cover. No user serviceable parts inside. Refer servicing to qualified service personnel.

Safety: Labelling Conventions

CAUTIONRISK OF ELECTRIC SHOCKDO NOT OPEN

AVISRISQUE DE CHOC ELECTRIQUENE PAS OUVRIR

This symbol indicates that dangerous voltage constituting a risk of electric shock is present within this unit

This symbol indicates that there are important operating and maintenance instructions in the literature accompanying this unit.

Prior to connecting mains, check the supply voltage is correct and the mains lead is OK.

Avoid ingress of water or particles into the enclosure.

If the mains fuse blows continually, refer the unit to qualified service personnel.

Placement

Keep the unit out of direct sunlight and away from heat sources.

Keep the unit away from moisture or dusty environments.

Avoid locations where liquids may be spilled onto the unit.

Ensure that any supporting structures have adequate load capacity for the weight of the unit.

Ensure adequate space for cooling to the rear panel and easy access for controls and connections.

Cleaning

Use a soft cloth with a neutral detergent to clean the cabinet, panel and controls.

To avoid damage, do not use solvents to clean this equipment.

Rear Panel Layout

1. INPUT LEVEL control
2. Line level INPUT XLR
3. Phase switch
4. Line output THRU XLR
5. FREQUENCY control
6. Power ON/OFF switch
7. IEC mains power inlet

Setup & Operation

With INPUT LEVEL turned fully down and power switch off, connect the IEC to an appropriate mains outlet.

Connect output of mixer or any line level signal to the INPUT via XLR. If the signal is to continue to further active speakers, connect these from the THRU line level XLR.

Begin with the FREQUENCY control in the mid position (12-o-clock position)

Press the power switch on and gradually increase the INPUT LEVEL until the bass signal is heard through the speaker.

Turning the FREQUENCY control up will include more mid frequencies and turning it down will eliminate all but the lowest frequencies. Adjust the FREQUENCY control to the desired tone, noting that lower settings may need the INPUT LEVEL turning up to compensate for the narrower frequency band.

The PHASE switch can help eliminate speakers which are "out-of-phase" from cancelling each other's signals out. The correct setting for this switch is whichever setting gives the loudest output – by a process of trial and error. One or other setting may also help to avoid feedback. If there is no difference in volume or feedback, leave the switch in the "0°" position (out)

To avoid loud noises when powering down, turn down the OUTPUT LEVEL before switching off.

Specifications

Model	QT15SA	QT18SA
Power supply	220-240Vac 50/60Hz (IEC)
Cutoff Frequency	40 – 150Hz
Connections	XLR line in, XLR line out
Main driver	38cm (15") 8Ω	45cm (18") 8Ω
Output handling (max)	600W	1000W
Dimensions	515 x 420 x 615mm	585 x 475 x 675mm
Weight	22kg	29kg

Troubleshooting

No output and no LEDs lit	Check POWER switch is on
	Check mains lead is connected properly and fuse hasn’t blown
Power LED lit but no sound from external inputs	Check signal leads are OK and connected properly
	Try turning up the FREQUENCY control
	Ensure input signal has some bass content for the sub to produce
	Check INPUT LEVEL control is not fully down

Disposal: The "Crossed Wheelie Bin" symbol on the product means that the product is classed as Electrical or Electronic equipment and should not be disposed with other household or commercial waste at the end of its useful life. The goods must be disposed of according to your local council guidelines.

Errors and omissions excepted. Copyright© 2021.

AVSL Group Ltd. Unit 2-4 Bridgewater Park, Taylor Rd. Manchester. M41 7JQ

AVSL (EUROPE) Ltd, Unit 3D North Point House, North Point Business Park, New Mallow Road, Cork, Ireland