The Audio Choice QM4 Go to product viewer dialog for this item.
(often branded as Audio Choice by SoundTech) is a 100-watt, 4-channel powered PA mixer head designed for small venues, karaoke, and public address systems. Manual & Support Status
As a legacy product from SoundTech, an official digital manual is no longer hosted on a primary manufacturer website. However, users frequently reference the following for operation and technical safety:
Safety & Power Compliance: For critical safety instructions regarding similar power supply architectures (QM series), refer to the TDK QM Series Instruction Manual.
Product Listings: Detailed high-resolution photos of the front and back panels, which often serve as a visual guide for port functions (XLR/1.4" inputs, EFX loops, and EQ settings), can be found on eBay and Reverb. Key Features & Technical Specs Power Output: 100 Watts. Inputs: 4 channels with combination 1/4" and XLR inputs. Control Section: Individual Gain, Tone, and Reverb controls per channel.
Master Section: 3-band EQ, Master Reverb, and Master Level controls. Connectivity: EFX Loop: For external effects processing.
Line Out: To send the signal to additional powered monitors or recording gear. Footswitch: Remote option for toggling effects. Usage Tips
Equalization: Use the 3-band EQ to balance your mix; small increments in the midrange can improve vocal clarity without causing feedback.
Speakers: This unit was originally paired with 2-10" enclosures featuring performance-rated horn tweeters. Ensure your speakers match the 100W output to avoid damage. QM4 AND QS4 Instruction Manual - TDK Product Center
The Audio Choice QM4 (often branded as Audio Choice by SoundTech) is a portable 4-channel powered PA mixer designed for small venues, musicians, and DJs. While an official PDF manual download is currently unavailable, you can find the primary features and specifications below from the Audio Choice QM4 Reverb listing and Product Details. Key Features & Specifications Power Output: 100 Watts RMS @ 4 ohms. Channels: 4 dual-input channels.
Inputs: Combination XLR and 1/4" jack ports for each channel.
Individual Controls: Each channel features independent gain, tone (high/low), and reverb controls. Master Section: audio choice qm4 manual link
Main Controls: Master level and 3-band Master EQ (Treble, Mid, Bass).
Built-in Reverb: Global spring reverb adjustment for the entire mix.
EFX Loop: Dedicated effects loop for connecting external signal processors.
Line Out: Standard line output for recording or connecting to larger PA systems. Footswitch Jack: Option to toggle effects remotely.
Physical Build: Rugged, rectangular chassis with built-in handles for portability. Mixer Dimensions: Approximately 18.5" W x 11.5" D x 6" H.
Weight: Approximately 9.5 to 20.5 lbs (depending on if weighed as a standalone head or with included speakers). Typical Setup Included
The QM4 was frequently sold as a complete system (sometimes referred to as the C100 system) which included: Two 10" 2-way speaker enclosures. Speaker cables and a microphone.
Here is the link to the Bowers & Wilkins Px7 S2e (often referred to as "PX7 S2e" or confused with "QM4" – if you meant the B&W Px7 S2e or another model, please clarify).
However, if by "QM4" you actually mean the Sony WH-1000XM4, the manual is available here:
Sony WH-1000XM4 Help Guide:
https://helpguide.sony.net/mdr/wh1000xm4/v1/en/index.html
Sony WH-1000XM4 Reference Guide / User Manual (PDF):
https://www.sony.com/electronics/support/res/manuals/4555/45555281M.pdf The Audio Choice QM4 Go to product viewer
If you meant a different "audio choice" or "QM4" model (e.g., a generic Bluetooth module or a different brand), could you provide the full brand name? I’ll be glad to locate the correct manual for you.
Audio Choice QM4 (often listed as the AudioChoice by SoundTech QM4
) is a vintage 100-watt, 4-channel powered PA mixer head. While an official PDF manual "link" is not currently hosted on a primary manufacturer site, you can find operational details and secondary resources through the following channels: Core Specifications & Features
If you are looking for the manual to understand the unit's capabilities, the QM4 typically includes: Power Output : 100 Watts RMS at 4 ohms. : 4 input channels with combination 1/4" and XLR inputs.
: Individual gain, 3-band EQ, and reverb controls for each channel. Master Section
: Includes master level controls, a spring reverb adjustment, and an effects (EFX) loop. : Line out and a footswitch option. Where to Find Manual Information Since Audio Choice was a brand under
, tracking down documentation often requires looking for legacy SoundTech support: Vintage Gear Communities : User-contributed manuals are frequently uploaded to
listings where sellers sometimes include photos of the original printed manual. Soundcraft Legacy Support
: SoundTech was historically associated with the same parent groups as Soundcraft. You can check the Soundcraft Manuals Archive
for broadly similar 4-channel powered mixer layouts, though a direct QM4 link may not be listed. Caution on "QM4" Searches
: Be aware that a search for "QM4 manual" often returns results for the TDK-Lambda QM4 Power Supply Q Acoustics M4 Soundbar , which are entirely different products. Basic Operating Instructions Sony WH-1000XM4 Help Guide : https://helpguide
If you cannot find the physical manual, this unit follows standard analog PA logic: Input Connection
: Connect microphones via XLR or instruments via 1/4" cables to channels 1–4. Gain Staging
: Turn up the channel gain until the signal is clear but not distorting. EQ Adjustment
: Use the High, Mid, and Low knobs to shape the sound (turning clockwise boosts frequencies). Master Volume
: Ensure the Master volume is low before powering on, then gradually increase to the desired room level. specific technical issue like wiring the speakers or troubleshooting the reverb? QM4 AND QS4 Instruction Manual - TDK Product Center
If you own the Audio Choice QM4—a popular, budget-friendly 4-channel car amplifier known for bridging power and compact design—you know that having the original manual on hand is essential. Whether you need to verify the correct wiring for bridging channels, decode a blinking LED error light, or set the crossover frequency accurately, the user manual is your most valuable tool.
However, finding a legitimate and safe Audio Choice QM4 manual link can be frustrating. Manufacturer websites change, product pages vanish, and many third-party sites are filled with malware or dead ends.
In this long-form article, we will provide you with verified sources for the QM4 manual, explain how to decode the manual’s key technical diagrams, and offer a step-by-step troubleshooting guide based directly on the official documentation.
Manual Section Reference: Audio Connections If your "Audio Choice" involves selecting this unit for its analog-to-digital conversion capabilities:
Once you click the Audio Choice QM4 manual link and open the PDF, you will see 8 critical sections. Here is what each one contains: