Any thoughts would be appreciated. My D-115 is acting up in the following way. Within the first minute or two of turning it on, I get a wah wah
warbling sound coming through the speakers. This usually lasts for 30-60 seconds, after which time the amp performs flawlessly as long as I have it on. AR thought it might be the caps. I then had them changed locally. All tubes check out fine and biasing is correct but problem persists. I'd like to deal with this locally ( Metro Detroit ) if I could. Thanks in advance for any guidance.
Dave
warbling sound coming through the speakers. This usually lasts for 30-60 seconds, after which time the amp performs flawlessly as long as I have it on. AR thought it might be the caps. I then had them changed locally. All tubes check out fine and biasing is correct but problem persists. I'd like to deal with this locally ( Metro Detroit ) if I could. Thanks in advance for any guidance.
Dave