: Includes an EFX Loop , Line Out for recording or daisy-chaining, and a footswitch jack for remote reverb toggling.
: If the sound is "crunchy," lower the channel gain and increase the master level instead. audio choice qm4 manual better
The QM4 uses a switching power supply that can introduce a 60Hz hum if ground loops occur. : Includes an EFX Loop , Line Out
On page 22, the manual shows a diagram of how to bridge Zone 1 and Zone 2 to create a single, high-power output for outdoor speakers. This is not intuitive from looking at the back panel alone. Users who skip the manual often assume the QM4 is underpowered when, in reality, they simply haven't activated the bridging sequence (which involves specific Dip-switch combinations listed only in the manual). On page 22, the manual shows a diagram
| Problem | What the Manual Says | What Actually Works (Better) | | :--- | :--- | :--- | | | Check speaker wires. | Check if Zone 2 is muted via the RS-232 control. The front panel won't show this. Cycle power. | | Remote control works intermittently | Replace batteries. | The IR sensor is behind the LCD glass. Clean the glass with microfiber. Also, fluorescent lights interfere—move the unit. | | One channel is louder than the other | Balance settings. | The QM4 has a digital balance that drifts. Go to Menu > Zone Config > Balance. Set to "0" even if it shows "0"—re-select it. | | Unit shuts off at high volume | Reduce volume. | Your speaker impedance is too low. You need 8-ohm speakers. If using 4-ohm, only use two zones max. The manual omits this thermal calculation. | | Hum on Input C only | Check cable shielding. | Input C shares a ground plane with Input D. Use a ground loop isolator or cut the shield on one end of the RCA cable. |
: You will learn whether to use balanced (TRS/XLR) or unbalanced (TS/RCA) cables to eliminate annoying background hums and ground loops. Phase Alignment