Sorry this is going to be long.. but I need to mention everything... so you all get an idea of what i've been doing to try and solve my problem.. and maybe it will generate some ideas from someone in here about what might be the cause of my problem.

I had the 990 hooked up to a 2 ch Adcom GFA-5400 amp. Every once in a while.. the right channel would crackle and die out. It was rare, but it would happen about once every other month or so.

About a month ago.. it cut out again. I wiggled the RCA connector on the back of the Adcom amp.. and got it working again. So i figured something was wrong with the amp.. loose connection inside.

The next day i go to fire up the system.. and i hear a "pop" from the right speaker. Oh no. Yup.. the amp fried the crossover in my Polk Audio tower speaker. Only the tweeter would work..the two other mid drivers would not.

Ok. Crossover is replaced... and during the time i'm waiting for the crossover.. i decide to take the Adcom amp in for repair. Sure enough.. they found broken wires on the inside.. connecting to the RCA imputs. Fixed.

In the meantime when the Adcom is in the shop, I use a older NAD 2600A amp in it's place. Fine. Sweet, sounds really good and better than the Adcom.

4 days later.. BAM! same exact problem creeps up.. the right channel is cutting out again.

So i replace the RCA IC from the 990 to the amp.. good to go again. Two hours later, it starts to cut out again at low volumes. If I raise the volume on the 990, the right channel comes back on.

So that brings you up to speed. The only thing I have not changed out.. is the 990 pre itself.

What do you think is going on with the right channel cutting out using two different amps? The NAD was given a clean bill of health.. no problems whatsoever.

Could a problem devlop with the 990 right channel output connector? If so.. how would I check it out? It's bugging me of course.

thanks for any and all suggestions. I have also replaced the speaker wires on both the left and right fronts.

anyone have any clue what may be causing my shorting out problem? If it is a pre amp output problem. what the course of action to take to get it fixed by the Outlaws?

thx

I wonder if the broken wires on the Adcom amp would have done anything odd to the 990's output? Seems like a less-than-likely scenario, but it would also be odd to see a right channel pre-amp output and a right channel amp input come up lame at the same time - and there does seem to be something amiss either at the 990's pre-amp output or in the speaker cable itself. Have you tried swapping the left and right pre-amp cables at the 990 to see if the problem shifts over to the left speaker (indicating that the right pre-amp output is up to something)? As for getting help from Outlaw, just give them a call and bring them up to speed. They'll work with you on it.

Hi Skyblazer,

I'm having the same problem with my center channel. I actually sent the 990 in for service, and the outlaws found nothing wrong with it. They say a bad amp channel would not exhibit this behaviour. All they tell me to do is reinstall the software. I'm still having problems. I have a thread from 11/27 that discusses my issues:

http://ubb.outlawaudio.com/ubb/ultimatebb.php?/ubb/get_topic/f/34/t/001028.html

Edited to say that I spoke with Outlaw about my issue, and we're trying to work it out.

wow.. snakeoiler... i guess it could be a software problem. I never even considered that. In your case it didn't solve your problem... i wonder what the problem could be?

There must be something wrong.. I haven't had a chance to delve into my problem anymore.. been to busy. I will do what gonk recommended to do.. and swap the left and right channels.. and see what I get.

I know it can't be a amp problem in my case... because I get the same exact results using two different amps.

It almost appears to me that the pre amp level is not sending the correct voltage to the amp for that one channel. It cuts out at low volumes.. and when I raise the volume.. it comes back.

I will explore this some more over the holidays.

good luck with your problem snakeoiler. Something just isn't right in your case and mine.

I'd be interested to hear what suggestions Outlaw gives you to help resolve your problem. Good luck.

Update.. now both channels on my stereo amp are cutting in and out. so i will be taking the NAD 2600A amp in for service. seems two stereo amps developed the same exact problem. does that seem weird to anyone else besides me?

I'll concur on the weirdness. I did some testing one time using pre-amp outputs into self-powered computer speakers. Might be an interesting low-tech test of the pre-amp outputs themselves...

It does seem weird. I noticed from your signature that you have Polk Audio SDA SRS speakers. I am a vintage Polk owner (RTA-12Cs) and have heard some SDA owners at the Club Polk forum mention amp shutdown problems in certain configurations.
If you didn't change anything there, I guess there is no reason to suspect that, but I thought I'd give you another place to look. Good luck and let us know things turn out.

ok. this explains the problem I am having with my NAD 2600A amp.. read below.

POWER AMPS:
that's exactly the problem I am having now. both channels on the amp are cutting out. when the volume is raised they sort of come back.

I guess it's not surprising that an older amp would now start to have these kinds of problems. It has served me well till now.

What do you all think about the repair/upgrades this service center does to the amp? I think i'll send to them for the repairs.

Here is the link to the repair center. I read most of their website.. I like their work ethic on repairing older higher end stereo equipment.

In House Stereo Repair high end

it's true.. the SDA's need a common ground amp... or the amp or speakers could be damaged if a non common ground amp is used.

Most people think the SDA"s need tons of power to run them.. yes more power is better. But i have run my SDA SRS"s with as little as 45wpc. Using an old Yamaha int amp. As long as the amp can handle a 4ohm load.. and is common ground.. they will run the SDA's.