Hello Everyone,
Yesterday, my adcom preamp died. I left it on without playing music for about two hours in active mode. The source was on aux 1. And the cable was laying on the floor. I observed no short circuit. Then I smelled a horrific chemical smell emanating from the preamp grill. To investigate the problem, I decided to play a CD in the Adcom GCD-750. No sound until I turned the attenuator all the way to the max, then id only hear faint music playback and alot of crackling, like a really dirty record playing. The smell at this point began to overtake the room and I began getting lightheaded. I opened a window for ventilation.
I checked the passive mode and it played perfectly. Note: In passive mode the smell continued to reek a chemical smell.
Today, I unscrewed the cover on the preamp to see if anything visually looked abnormal. There was a layer of dust.
Looking down at the motherboard while playing music , I sniffed around the motherboard trying to find the source of the odor. I located it to be in the top left portion of the motherboard. I found a hot black blob over D35 . There is a row of red Diodes labeled D32 to D38 from left to right horizonatally. The contacts on the top of the diodes look like they shorted to the neighboring diodes.
MY question is...to adcom experts, would these bad diodes likely be the reason why my active mode isnt working well anymore. Is it possible something else simultaneously fried as well like a capacitor but i am unaware of it. Does anyone know where I can find replacement diodes if these red guys are even indeed diodes?
All the help is appreciated.
TODD
