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square wave performance: measure better, sounds worse?

24.140.13.4

I was testing my new SE 6BQ5 amp on the scope. ESE125 OPT's had a bit of ringing at 1KHz and looked terrible at 10KHz. I bypassed the 1K Feedback resistor with a .0047uf cap. That made everything look better, almost perfect at 10KHz, but when I listen to the amp, the high end was attenuated too much. Too much mid and bass, with no highs.

I wonder if I filtered out the highs with this cap?

I've seen some schematic where a pf value cap is used across the feedback resistor, so I gave it a try.

It sounded better without the bypass cap. Oh well, At least my sine waves look decent on the scope.

maldar

Follow Ups:

have you try your amp without any feedback at all? - lovetube 05:35:59 07/06/08 (1)
- RE: have you try your amp without any feedback at all? - maldar 06:24:59 07/06/08 (0)
RE: progress - maldar 17:38:21 07/05/08 (3)
- progress!! - Solder n Listen 20:55:55 07/05/08 (2)
  - Transcendar Audio Transformers - Neff 10:16:43 07/06/08 (0)
  - RE: progress!! - maldar 06:51:28 07/06/08 (0)
(mis)-Interpreting measurements - Solder n Listen 15:16:39 07/05/08 (1)
- RE: (mis)-Interpreting measurements - Michael Samra 16:34:46 07/05/08 (0)
RE: square wave performance: measure better, sounds worse? - JimL 07:53:58 07/05/08 (0)
RE: square wave performance: measure better, sounds worse? - Jim McShane 05:20:23 07/05/08 (10)
- RE: square wave performance: measure better, sounds worse? - PakProtector 06:52:56 07/05/08 (9)
  - RE: square wave performance: measure better, sounds worse? - Michael Samra 07:32:45 07/05/08 (8)
    - RE: square wave performance: measure better, sounds worse? - Eli Duttman 11:23:51 07/05/08 (7)
      - Excellent idea Eli - Michael Samra 16:45:06 07/05/08 (0)
      - ultimately... - PakProtector 12:54:13 07/05/08 (5)
        
        Amen Doug........ - Neff 10:18:58 07/06/08 (2)
        
        RE: Amen Doug........ - PakProtector 14:06:45 07/06/08 (1)
        
        RE: Amen Doug........ - Michael Samra 13:11:13 07/09/08 (0)
        
        Absolutely, and add good design to the list! (nt) - Naz 04:17:43 07/06/08 (0)
        
        RE: ultimately... - Eli Duttman 13:19:43 07/05/08 (0)
RE: square wave performance: measure better, sounds worse? - boris_the_blade 20:54:31 07/04/08 (0)
RE: square wave performance: measure better, sounds worse? - PakProtector 20:07:06 07/04/08 (0)
RE: square wave performance: measure better, sounds worse? - Michael Samra 19:41:28 07/04/08 (0)
RE: square wave performance: measure better, sounds worse? - Tom Bavis 19:29:01 07/04/08 (0)

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