Finding or Replacing Components

Sound Diver · Joined: Mar 26, 2010 Posts: 16 Location: Preston U.K

I'm in the process of building a 24Db filter, State variable filter and a Quantizer, i seem to be having problems finding a couple of items in the UK, namely 2nF Caps & 49k9 resistors. Now i Know Ray has gone to a lot of trouble to arrive at these values but is it a good idea to replace 49k9 res for a 50k res and replace 2nF cap for a 2.2nF cap without screwing the circuit's up. I can find the resistor but it would mean buying it from major suppliers at a premium rate.

prgdeltablues · Joined: Sep 25, 2006 Posts: 146 Location: UK Audio files: 8

Not built those particular modules, but from the schematics, neither value is likely to be critical. The 49.9k resistors are just limiting the range of the resonance pot - you could use 47k there without noticing it. And the 2n cap is stated as ceramic, so unlikely to be better than 20% anyway - 2n2 should do fine.

ashleym · Joined: Aug 20, 2009 Posts: 157 Location: uk

I had the same issue and just used standard parts. In my case it was for an Ultimate and everything works OK for me. Any problems I can put down to analogue warmth.

For the quantiser you can get the precision resistors from Rapid (as you are in the UK)

http://www.rapidonline.com/Electronic-Components/0-4W-0-1-15ppm-Precision-metal-film-resistors-60260