Fender Deville - Same Issue, New Question

[mikeboone]

I recently found that the first two filter caps (C34&C35) are bad and were causing a loud hum on the output.

They are 100uF/350V caps. I have some 220uF/350V caps that I threw in there to verify my findings and the noise is gone, amp works good.

The issue - The guy it belongs to is suddenly "strapped" for cash and says that will do,doesn't want to pay alot and doesn't want to wait.

Is there an issue leaving those 220's where the 100's were? I know that in typical linear supply design, more filtering is a good thing. Does the same hold true in tube amp power supplies?

Thanks...
Mike

[Rob Mercure]

You'll probably never notice the difference - but there is the "ethical' issue of your friend "sticking" you with a partial repair. If this is casual everything is fine - if there was a promise to pay for a "correct" repair then he "owes" you - an apology if nothing else.

Rob

[Enzo]

Does he expect your "wrong" caps for free???

[mikeboone]

No, nothing is free... This amp had a multitude of issues and I was going to fix them all. He agreed to take it in this condition for 1/3 the quoted repair price with no expectation of warranty. In addition to the filter cap issue...

- Low voltage supply was inop
- Reverb tank is tanked
- Jacks had broken solder joints
- The end of the power cord was frayed offering up a nice 120VAC greeting to the un-wary. I replaced it for my own safety.

Aside from the reverb tank, all these issues were broken solder joints that I ferreted out. I was going to replace all those junk jacks with Switch Craft, buy a new reverb tank and do a full cap job. The amp is 15 years old and I didn't see the point in changing 2 of the 6 caps.

Those jacks are going to fail again, soon.

The big moral issue is that this amp is not even his and I am giving back to him in this condition.

I am guessing since you guys have not mentioned any other technical issue, the 220's are going to do the job.

Amp repair is fun, its the owners that make it a hassle!!!

Thanks for the help gents...

[PRNDL]

With all of those issues, the estimate may have been high enough for your friend to decide it may be better to sell the amp cheap and buy a new one.

This is a common calculation that you may want to keep in mind when providing estimates.