MUSES72320 Volume Control Board with Ground Sensing Output
High performance active volume control with balanced differential input and ground-sensing output (goodbye cross-channel ground loops!), based on the MUSES72320 volume control from New Japan Radio Co., Ltd. (NJR), part of NJR's MUSES series of high audio performance integrated circuits.
It can serve as:
- Part of an integrated amplifier (great with LM3886 or similar chipamp based power stages);
- With an input selector, a high performance balanced line stage or a minimalist analog preamp;
- An output stage for a DAC to form a "digital preamp".
This board uses the MUSES72320, a high quality digital volume control chip from NJR, for adjusting volume. Also available digitally controlled variants based on WM8816/MAS6116 or PGA2310, as well as analog variant with a dual linear potentiometer .
Features and benefits:
- Balanced differential input with excellent common mode rejection - works very well with single ended sources, too!
- Output stage that can be configured as balanced - best for downstream stages with differential input - or ground sensing (a.k.a. ground cancelling) - best if followed by a single-ended input referenced to its local ground, such as the vast majority of audio power amps;
- Compact (2.9x2.6in or 74x66mm) two layer PCB, all easy to solder though hole parts except for the MUSES72320, which only comes in a surface-monunt package.
The MUSES72320 is controlled via its SPI interface and requires a microcontroller. You can use anything suitable, such as a 5-volt Arduino. To help you get started, we provide a simple Arduino sketch.