- The MoRC is already capable of reproducing the most important frequencies for Bass so as a result it will also be fine for guitar. Since the guitar will not reproduce frequencies below what it is capable of it is not really necessary to cut off frequencies at the pedal itself. Technically you could add even more low Bass response by adjusting C1 and C12 at a glance to perhaps 100nF or 220nF (use sockets and test).
- Not sure on a calculation so Attack Time 4mS at center ATTACK setting and Decay Time 1.2 Sec is the only interesting answer I found.
- Close to 10:1 or higher. The MoRC circuit is more a limiter than a compressor. The Sustain (Sensitivity) control sets the threshold at which the limiter begins to act… when the signal goes higher than the threshold, there is a short knee as it kicks in, then the output is clamped to a fixed level. The threshold can be varied in a range from about -25dbv to -50dbv. When you have the Sustain control set high, it is only limiting the peaks, and it sounds like mild compression. As you adjust the threshold lower, more and more of the signal is limited so it sounds somewhat like a higher compression ratio.
Many people have analyzed this circuit and others and just about anything you would need to know can be Googled such as in this very informative LINK. While ours may be slightly different mostly everything can be applied to the Ross.
Thanks for the Build doc.