Capacitor

Demsy · 3217

0 Members and 1 Guest are viewing this topic.

Offline Demsy

  • Full Member
  • ***
    • Posts: 112
on: September 28, 2012, 03:57:51 PM
Hi, would changing the 0.1uF coupling cap on the output stage grid with the Russian teflon bring any improvement? I still have several of them, if it is better than the stock caps, why not use them.

Thanks for any input.



Offline Grainger49

  • Hero Member
  • *****
    • Posts: 7175
Reply #1 on: September 28, 2012, 05:50:27 PM
In the 300B version of the Paramount there is an interstage coupling cap of 0.1uF.  If you change it with a KK Teflon it will definitely change the sound.  You should break the capacitors in first for a minimum of 100 hours (4 days). 

Break In Post



Offline Demsy

  • Full Member
  • ***
    • Posts: 112
Reply #2 on: September 28, 2012, 06:15:17 PM
Thanks for your input, Grainger. Yes it is the 300B version I'm busy with. I also have read your writing regarding the burning in device for the capacitors, very helpful!



Offline Grainger49

  • Hero Member
  • *****
    • Posts: 7175
Reply #3 on: September 29, 2012, 04:01:47 AM
I just wanted to be sure.  IIRC the Parafeed cap is something like 3.3uF. 



Offline STURMJ

  • Sr. Member
  • ****
    • Posts: 279
Reply #4 on: September 29, 2012, 05:16:13 AM
He is talking about a cap that is on the grid resistor. That one is 0.1uf. I had upgraded mine, I did it in the initial build so I can't say if it made a difference.  I know that the 3.3uf is a worthy upgrade, I too would be interested to know if the 0.1 would make a difference.



Offline Grainger49

  • Hero Member
  • *****
    • Posts: 7175
Reply #5 on: September 29, 2012, 06:42:28 AM
Yup, got it.  According to the schematic the driver plate is connected to the output grid with a 0.1uF cap with a 249k load resistor to ground.  The grid stopper resistor, 220 ohms or there about, is the actual connection to the grid but in electrical terms, for audio frequencies it isn't there.  It stops RF oscillation.



Offline glynnw

  • Full Member
  • ***
    • Posts: 162
Reply #6 on: September 30, 2012, 10:01:04 AM
Replacing the stock .01 cap with a Vcap Teflon was a VERY noticeable improvement, and not of the kind "I think this wire is better".  It was immediately apparent that the amp sounded better.  Several months prior to that I  put in a Mundorf gold 3.3 uf (or some such - memory getting bad) which created a much smaller improvement

PC, J River software, opticaRendu, Schitt Ygg DAC,Tortuga Pre, Torta Radu tube buffer, Linear Tube Audio ZOTL10, Spatial Audio X5w/pair of GR Research dual 12" open baffle servo subwoofers tamed by DSpeaker Dual-Core DSP , Audience AU24 SE  spkr cable, handmade silver interconnects,