Old Bitnner XV1000 amplifier - one channel dead until warmed up, looking for schematic/company info
Hi everyone,
I'm trying to repair an old Bitnner XV1000 stereo power amplifier (at least 20 years old, possibly older). It drives two passive PA/DJ speakers.
What i noticed:
- Left channel works normally.
- Right channel often produces absolutely no sound when the amp is first powered on.
- The right channel's signal LED still shows activity, but there is no audio output.
- After 30 minutes to 1 hour of being powered on, the right channel sometimes starts working again.
- Once it starts working, it may continue working normally.
- Speakers and speaker cables have been tested and appear to be fine.
- I opened the amplifier, cleaned dust, and after reassembling it the fault temporarily disappeared.
- The amplifier appears to have been repaired in the past.
- There are several areas on the PCB that show signs of heat discoloration around components that run hot.
- I found one location where a component appears to be completely missing and the PCB underneath is darkened. On the corresponding circuit of the other channel, the same component is present but the surrounding area also shows signs of heat damage.
- There are a few other components that look heat-stressed on both channels, although none appear obviously exploded or catastrophically damaged.
- The amplifier contains Potter & Brumfield relays (photos attached).
- The right channel SIGNAL LED still responds to audio even when there is no sound output from the speaker.
Possible causes I was considering:
- Cracked solder joint
- Speaker protection relay
However, I'm open to other ideas.
I've attached photos of the amplifier internals.
Does anyone recognize this amplifier or know who manufactured Bitnner equipment? I'm also looking for a service manual or schematic for the XV1000.
Any advice on where to start troubleshooting would be appreciated.
Background**:**
The amplifier and speakers were originally used by a DJ at a factory. My father bought the system around 20 years ago. I've been using it for the last 3+ years for birthdays, summer parties, and other events.
My father says the amplifier had this issue years ago as well. Interestingly, I used it heavily for around a year and a half without noticing the problem, and only recently it started becoming obvious again.
Maybe its a curse because i blasted new gen music on it hmm..