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Hoffman Amps Forum image Author Topic: Post Filter Cap Depression  (Read 1714 times)

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Offline TerryD

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Post Filter Cap Depression
« on: December 21, 2015, 08:34:27 pm »
Does anyone else get bummed when they change filter caps.  My caps in my PA 100 were Mallory.  They sounded beautiful, but were bubbling a little bit.  I put in F&Ts because of some of the rants about new Spragues being a small cap in a large can etc.  Then I wonder if I should have got the spragues. 

I didn't get my bulb limiter going so I just gave them the full blast.

I don't know.  Amp seems a bit harder now.  different midrange character.  Not as sweet.  That's why I did the caps before fooling around, so maybe I can undo that.  Any thoughts?

Offline jojokeo

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Re: Post Filter Cap Depression
« Reply #1 on: December 22, 2015, 10:51:58 am »
To answer your question, to me it's something that you should be happy about knowing it's a part of maintenance reality sooner or later and there are some nice benefits to going through the trouble and expense. If you used the same cap values there "shouldn't" be any real negatives about it. But you didn't mention this or if you did any voltage checks before and afterwards that could justify/quantify your suspicions and therefore provide a point of reference to adjust later if needed?
To steal ideas from one person is plagiarism. To steal from many is research.

Offline jjasilli

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Re: Post Filter Cap Depression
« Reply #2 on: December 23, 2015, 03:05:36 pm »
Cap values may have drifted.   Sometimes the drifted values may sound better to someone tHan stock values.  If you saved the old caps and the right meter you can measure them and use those values.

 


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