| Component | Typical Value/Part | Notes | |-----------|--------------------|-------| | Op-amps | TL072, NJM4560, NE5532 | Use low-noise versions. | | Faders | 60mm 10kΩ logarithmic (stereo) | Proprietary size – order from Behringer or ALPS. | | Pots | B10K, B20K, A50K (rotary) | Note the shaft type (splined or knurled). | | LEDs | 3mm red/green/yellow | For channel peak, mute, phantom power. | | Power supply caps | 1000µF/25V, 470µF/16V | Replace if swollen. | | USB jack | USB Type B 4-pin | Prone to physical breakage. | | Headphone jack | 1/4" stereo switched jack | Contact failure common. |
A frequent complaint with USB mixers is the computer failing to recognize the device or hearing a high-pitched whine in the background. The service manual details the USB codec chip and its clocking circuit. It reveals whether the grounding scheme is adequate. Often, "fixing" USB noise involves adding a ground lift or modifying a shield connection—procedures only possible with the board layout in hand. behringer xenyx qx1202usb service manual
However, you can effectively service and troubleshoot this mixer using a combination of the available user documentation and shared schematics for the base "1202" series. Essential Documentation | Component | Typical Value/Part | Notes |
(502, 802, 1002, 1202) that share many of the same preamp and EQ designs as the "Q" and "QX" series. Repair Guides | | LEDs | 3mm red/green/yellow | For
Use a highlighter. Trace the signal from input to output. Mark where the signal disappears. That’s where the faulty component lives.