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previous: Jukka Tim C , you mentioned here a someti... -- 9/24/1999 10:05 AM View Thread

RE: voodoo , TIM C ? Vintage Club mods

9/25/1999 1:44 AM
Tim C.
RE: voodoo , TIM C ? Vintage Club mods
The Crate "Vintage Club" amp I modified had 750pf caps across both the normal volume pot and the overdrive volume pot. I removed both of those. The owner brought the amp in to be modified because he thought it was harsh and brittle in both channels. He also did not like the overdrive toneas he thought it to be muddy.  
In answer to your questions I offer the following:  
1) I would unsolder one end of the 220 pf cap on the normal  
volume pot and try the amp to see if you like that sound. It will make the normal channel less harsh. If it semms to lack highs with the 220 pf cap removed, try replacing the 220 pf cap with a 47pf instead. I think you will like that!  
2) The .047 cap to remove is the V2 coupling cap. Replace it with a .0047 cap. That will increase the overall gain a bit and change the midrange structure of the amp.  
3) Check the tone stack for the overdrive channel and let me know what values yours has. If memory serves me well you should have the traditional .1,.047,250pf tone stack with a 100k slope resistor. If that is the case, Change the .1 and .047 to .015mf@630v respectively and the 250pf cap to 390 pf. Change the slope resistor from 100k to a 47k 1/2 watt.  
4) If you amp has 25mf@25v cathode bypass caps on pins 3 and 8 of V2, remove them and replace them with .82mf@630v. caps(available from Angela Instruments).  
Let me know if I answered all your questions.  
Good luck,  
Tim C.  

Jukka Thanks TimDo you re... -- 9/27/1999 10:39 AM