Tube amplifier bad caps


Hey,

My integrated tube amp has been experiencing the symptoms of bad filter capacitors. Crackling in my amp is so bad on both channels that I'm afraid ALL of the filter caps will have to be replaced. Tube swapping and tightening the socket pins has had no effect so I'm lead to believe bad caps are the problem.
A pic similiar to the inside of my amp can be found here. Are the can caps or the axial caps what I should be looking at replacing? I'm confident I can do the repairs myself (purchasing caps, discharging old caps, soldering, etc.) since I'm afraid of what the price tag might be for such a repair by a professional repair shop.
hitman_hifi
I think your better off finding a qualified tech and have him troubleshoot the problem. All of the caps? that seems unlikely as the unit looks to be fairly new. Even at 40 to 50 dollars an hour I doubt the bill would be more than $200-300.
my experience has been that when filter caps get old you will hear more 60hz hum or buzz from the speaker. the problem you describe does not sound like a bad cap. It does sound like an issue with the power supply however. I agree with the others. Get an estimate with a qualified tech.
My guess is that the caps are fine. One of the switches on the front is the likely culprit. Move the switches back and forth and see if the sound crackles. If you find the one, use a cleaner like Rat Shack zero residue cleaner or a Caig product, or CRC. This should do it. Caps do not go bad often. If they go bad, they usually leak a yellow hard goo on the board. Replace quickly. This is an acid and will ruiin the board over time.
Hmm...now I'm second guessing. A lot of uncertainty as I've been told it's definitely the filter caps. However, the amp is not even 10 years old and I've been suspicious of this assessment. I've seen what cap leakage looks like and they definitely look fine.

I'll try and explain the problem in more detail. Upon startup, the "bacon frying" sound gradually builds and becomes constant once the tubes are lit. The power tubes flicker with every pop and crack. This symptom used to be only in the right channel and now it's in both. As indicated, I've swapped all of the tubes with new ones. I'm afraid I've probably ruined the new tubes because of this.

I purchased this amp used from a local hifi company that is out of business now. I live in a small city so finding a tech that specializes in tube amps will be difficult. Are there any fellow Canucks out there that know of a tech near Regina? As a last resort, I may end up contacting the UK manufacturer and seeing what can be done.

Thanks guys for your help.
You have probably NOT ruined the tubes because of this, unless one of the conditions below occurs. If your tubes are driven into oscillation over an extended period, then I would worry. Also, if your tube bias circuit goes bad somewhere and the tubes glow red-hot for an extended period, I would worry then, too. I am not sure if this is comprehensive, perhaps someone else may add to this. As far as my experience and my father's advice to me on a problem with my amp goes, this about covers it. He is a retired EE professor by the way.
Are your tubes glowing red-hot, or noticeably brighter than usual? If so, and you let them run this way for a while, get them tested. Otherwise, see how they sound after you have fixed the crackling problem. They should be fine.
Good luck with your amp!