For Sale : Extremely Rare ARP Minus Noise Mixer Very cool Piece especially if you are running multiple old synth. Features weird cool wonky reverb, plus depth and dynamic noise filter.   
Very rare model only 300 manufactured!
 
 Powers on and everything seems to work as it should, but scratchy -  defintely needs a deep clean. One wooden side panel is broke (see pics)  All that being said this piece is sold as-is!  
 Details -  "Features 8 Channels with 3 switchable levels of preamp gain (0, 20, and 40db). Each has 1/4" and XLR inputs, with rugged switchcraft jacks. Each channel has EQ in the form of Bass and Treble. The adjustments can be quite drastic and I really like the added bass it can give you. There is a Dry/Wet control for the onboard spring Reverb on each channel as well. The master section controls the main outs (a pair of xlr and 1/4" on the back). It has master gain, eq, effect level, and noise gate. The master eq gives the Low Freq a +10db boost, and the Hi Freq a +6db boost. The Noise gate actually works quite well. There is a built in spring reverb, but you can bypass it on the back by using the send/return to add an effect of your choose. There is also a mono monitor output and a stacking input on the back (I guess for linking mixers)."