Module is available as a DIY project only.
This Module is currently available.
Four Input Mixer with Pan Pots and Output Level Meter
The D102 is a four input mixer designed to drive external audio equipment. Each input goes directly into a level control, is then buffered and fed to the pan pot, and then the pan pot signals are recovered and buffered before being sent to the final stereo summing amplifier. The level meters use active rectifiers and smoothing circuits to give a good and accurate response. The classic LM3915 is used for each channel to drive five LEDs per channel with 6dB intervals. The calibration of each level meter is set by a 25-turn trim pot on the meter driver board. By default I trim the levels so that 0dB on the meters equals 1Vrms on the outputs. This design uses the NE5532 op amp for excellent audio performance and low noise. The meter driver uses TL082 op amps and the LEDs are driven at low current to reduce overall power consumption, however the NE5532s draw quite a bit of current.
Specifications:
Four channel audio mixer with input level and pan controls
Line level output suitable for driving external audio equipment
Dual 5-segment LED level meters show output level - calibrated to 0dB = 1Vrms
Very low noise design suitable as a master output mixer
Power: +12V @ 120mA, -12V @ 60mA
