Does anyone here have a real grey Ross Compressor? I was wondering what type of capacitors it used.
Are the 1uF and 10uF polarized caps tantalum or are they regular electros? Also, what type of capacitors are the non polarized caps? Polyester film, ceramic, metal film?
TIA!
Phillip
Had one but long ago sold it to some neohippie with daddy's credit card :D
But I can tell you that the polarized caps were tants, all of them, and that the rest of the caps were ceramic.
It was the basic, run of the mill, commercial effect, nothing fancy going on inside and cheap parts.
Jay
Thanks Jay! That will help greatly in my cloning efforts :)
I always get a kick out of Keeley's page where he touts those original-type 2SC1849 as sounding the best in the Ross...I'm sure that that were just the cheapest ones that they could get in large quantities...not necessarily the best sounding. I'll be using something more along the lines of the 2N4401 or 2N5088.
Can anyone recommend another type of transistor that sounds good in the Ross Compressor circuit? I'm about to make out a Mouser order and they could be included. I imagine that the European-made BC108 or BC109 transistors might sound really good since they have a very good reputation for being nice sounding transistors.
Phillip
Type - Vmax - Ic - MaxAmp - Pmax W - hFE?
____________________________________________________
2SC1849 NPN - 30 - 0.100 - 0.350 - 250 - 150
Just find a transistor near these specs and you're good to go.
Hope this helps.
RDV
P.S.
I bet 2N4401 would be perfecto!
Wow it looks like the 1849 is a pretty low gain transistor when operating at the kind of collector current found in effects pedals. With a gain of 150, I think that 2N3904s will work in their place pretty well.
Phillip
I've used 2N3904s with no problems or difference in sound for what I could tell. 2N4401s should work just fine as well. I would suggest getting the Reverse-Audio 500k pot from Steve at Small Bear for the Sustain pot, big difference in control from a linear pot.
Beyond that, audition a couple of CA3080s, the noise will vary between them, find the lowest noise chip. Personally I would also use all metal film resistors to reduce the noise further. I liked film caps for those in the signal path.
And most importantly, the first cap is 220 pf not .0022uF, this makes a big difference.
Hope this helps,
Jay Doyle
Thanks guys! Does anyone know how to add an "attack" pot to the Ross COmpressor? I know it's been done before, but I can't find any instructions on where to add it or how to add it.
Phillip
Well all of the ways that add an "attack" pot that I know of are actually adding a "decay" pot. There is no easy way to do it. You would have to either add the same resistance to both the FWR transistor emitters with a dual pot or put a buffer in along with a diode and a pot. Both of these are either really invasive to the circuit or will need a new board.
Sorry.
The decay mod is to turn the 150k resistor on the collector's of the FWR into a 50k and a 100k pot. Or something similar (100k resistor and a 50k pot etc)
Jay