Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Mars-Hall on March 20, 2020, 10:03:29 pm

Title: Super Reverb cap job, replace resistors?
Post by: Mars-Hall on March 20, 2020, 10:03:29 pm

Is it standard procedure to place all resistors on the cap board when replacing the caps or if they read good reuse them?  If I do replace, use metal film?

Title: Re: Super Reverb cap job, replace resistors?
Post by: nandrewjackson on March 21, 2020, 12:26:53 am

If they read good AND dont *look* fried, sure, leave them.  If one reads ok, but looks crispy, I'd change that one.


OR


if you have good parts in stock, go ahead and change them all out.

Title: Re: Super Reverb cap job, replace resistors?
Post by: Latole on March 23, 2020, 10:45:23 am

Tubes plates resistors may read good, look good but they come noisy. Replace them.

Title: Re: Super Reverb cap job, replace resistors?
Post by: jjasilli on March 23, 2020, 11:17:02 am

My procedure: replace the entire PS including plate R's.  Verify values of K R's and bypass caps, or just replace those too.


The reason is that the components in the PS tend to age together.  Replacing some components may trigger remaining components to fail resulting in a series of failures.  Maybe OK in one's own amp, but a customer may feel that the tech is incompetent.


IMHO the only reason not to do the foregoing is to keep a vintage amp as stock as possible.  With this I don't agree if the amp is to be used, and at least one component must be changed anyway.