2. tech-talk
  3. 1366545104

Amplifier Goes into Protect Mode Right Channel

Wanted to hear your tech thoughts on this problem. After spinning vinyl for 1-3 hours, the right channel on my solid state amplifier goes into protect mode. This repeats itself multiple times each session. I have a tube preamp and tube phono stage. Only one source - turntable. I've swapped tubes in the linestage preamp which made no difference; swapped IC cables which made no difference. The linestage tube preamp is new (one month old) but I'm beginning to think it may be a leaking cap causing the trouble. Also looking at the speaker cables as a possibility. Would that matter? Any thoughts? At the point where I'm ready to RMA the preamp for bench test. Thanks in advance.
wescoman

Showing 4 responses by wescoman

wescoman OP
117 posts
 
I had something happen similar to this issue one year ago when I bought the Ray Samuels Nighthawk phono preamp. The amplifier would go into protect mode while playing music. Before I checked the phono stage with the multimeter for DC leakage, I sent the amplifier back for evaluation. They could not find anything wrong with the protection circuit or anything else for that matter. When I returned the Nighthawk and went with ClearAudio basic phono stage, the amplifier stopped going into protect mode. So, I'm making a big leap here and assuming there's a connection but I could be completely wrong on this. I did run the multimeter on the preamp right channel output jack - it did register something but it was always intermittent. Does that provide additional helpful information?
wescoman OP
117 posts
 
Thanks for the recommendation. You're right, this is going to take an inordinate amount of time to isolate. I wonder if I should just contact CODA Technologies and cut to the chase and see what they say about the problem. I wonder if the right channel is going into thermal overload due to dust build-up or something like that. I could open it up and use a can of compressed air to clean it.
wescoman OP
117 posts
 
Thanks for the great ideas. I'll give them a try and see what happens when I get the speaker cable back from Acoustic Zen. First, I'll hook up everything as it should be and then wait for the right channel to shut down. Unless AZ detected problems with the right speaker cable, the shutdown should happen again. Then, I'll begin the process to reverse cables as suggested above, one step at a time, to isolate the problem. I also plan to contact CODA today and see if they have any thoughts on the subject.
wescoman OP
117 posts
 
Was on another website and got some great ideas. Need to check out speaker damping. My speakers sit directly on carpet. They come with spikes but I didn't install them. Maybe I need to use them or put some marble pavers underneath them. Secondly, recommendation to use turntable shelf instead of placing on butcher block and then on dedicated wood table. Third idea deals with tonearm/cartridge resonance issues. If indeed it is subsonic frequency issues, this could get complicated.
More to discover