Parasound Model 2100 Left Channel Comes In Late Off Minimum Volume

msg

I have a situation with a Parasound Model 2100 preamp where the left channel drops out completely at very, very low volume position. Put another way, the left seems to come in late, but then seems to matched up fine.

Works okay when up five hairs hair past minimum level, but at just off minimum, the right channel comes in as expected, but nothing from the left. Kinda weird. Sometimes I like to have the music very, very low.

Anyone have any ideas what this may be about? Weak output signal in the left output of the pre? It does it with any amplifier I use, so I think the problem is in the pre.

Anyone else with the 2100 notice similar behavior?

oldrocker

Never had that with mine. Will double check when I get back home, I'll try to re-create and let you know.

msg

great, thanks!

oldrocker

Been running for about 30 minutes up/down on the volume, letting it sit real low for a while now and have not be able to get that same result, running a 2250 with the 2100, seems to be working fine. Will let it run for a while more and if it happens to do the same thing, I'll let you know. Is it the same effect with the remote as to manual volume increase?

vcwatkins

Is it possible it's actually the amp? Behavior sounds like worn/dirty speaker relay issue in some Parasound amps.

oldrocker

Just a thought. A few months back, I had just the slightest amount of static at the volume staring increase. I pulled the volume knob, blew some air into it as I rotated the it back and forth and the static was gone. I have no idea if that actually worked somehow.

FYI, I'm NOT recommending anything as I'm not smart enough to fix stuff or give advice, but I did just remember I had that static issue once and even though your not having a static problem, that helped my situation.

Hope you get it resolved...

DaveHo

I wouldn't think a piece as new as a 2100 would need it, but have you tried some Deoxit on the volume pot? In warranty? Give Parasound a call.

msg

David, thanks for checking on that, and thanks for the other replies, fellas.

I'm pretty sure it's the same if I try a different amp, but frankly, I tried a bunch of different things while troubleshooting, and didn't make any notes, and now can't remember what did what. I'll run through it again and post up with what I find.

If it looks like the 2100, I'll send Parasound a message to see what they say. I don't think it's under warranty anymore as I bought it second hand about a year and a half ago with no idea of the history and no purchase receipt. I haven't used it much, so not sure whether this is new behavior at this point. Re: cleaning, I may give this a shot if it narrows down to the 2100 in the end. May be worth a shot, but it's pretty clean otherwise; no noise in the controls.

msg

I got myself all good and confused about this earlier while troubleshooting, but think I finally got it figured out.

To confirm, yes, the problem remains when I connect a different amp.
The problem remains even with different IC's.
Testing with an integrated
- Source and DAC sections + cables test good
- Speakers + cables test good

The troubleshooting details, and I'll skip right to the part that matters:

1. Base Configuration - Left channel low/slow to come in off minimum volume
2. At the amp, from the 2100, switched Left and Right IC connectors - problem "moved" to Right speaker.

If I'm understanding this correctly, this indicates an issue on the output path from the 2100. I think if there were a problem in the amp, the problem would have stayed on the same speaker, correct? I got myself all mixed up on this earlier by overthinking it, I think. I thunk about it real hard.

Does this confirm the issue to be at the outputs from the 2100?
Can I measure output voltage at these outputs on the 2100 with a meter? Or does this voltage vary independently on each change, respective to the signal coming through?

skrol

I had an old Denon receiver do something similar. When it was first powered on one channel was very low and it you goosed the volume it would then match with the other channel even at low volume. The problem seemed to go away after I touched up some questionable solder joints on the PC boards.

msg

Hmm. Thanks, maybe I'll pop the cover and have a look. I remember having something similar to what you describe with an old Sony receiver.