Up for sale is a custom cmoy built by Fred_Fred in Australia
I purchased this unit from him a few months ago, although have only used a handful of times as I purchased a desktop amp (NFB5) shortly after receiving this unit.
The Cmoy has a variable bass boost knob it also comes with OPA2227 and LM4562 opamps which are easily swappable. It currently has the LM4562 installed which I believe provides a more balanced sound.
I will include the gain switches...