The Amp Quits Agin -- Am I Missing Something?


I have a 4b-ST I left on for about 4 hours Friday night only to return to find that one of the channels had died in my absence. While I was gone, the system was on, but not being used. I haven't really investigated at all to guess what may be wrong, other than to determine that that CD player and the preamp are still working fine. The left channel on the Bryston seems to be working fine, as does my left speaker. The right channel, however, appears to be completely dead (even the left LED is dead) and I have no idea what may or may not have happened to my left speaker. I'd love to not have to send the amp back to the shop (again, it was there in February for a muting switch) and am hoping that I might have missed something obvious. Any thouhgts? Thanks.
mezmo
Ugh, as I suspected. My hope is that the channels are on independant fuses and that one of them went on me -- here's to hoping for the simple solution. Haven't checked them yet, but that's going to be the first (and likely the last) place I look when I start digging. And to add insult to injury, I just had $200 in new CDs delivered about 5 minutes ago. Darn lousey timing. (PS as for my apparent inability to tell my right from my left in the original post, what can I say? We'll keep it simple: on side work, other side no work).
on the plus side, you couldn't ask for better service than you'll get from bryston if something is wrong. my former amp was a 4b and it did indeed have a problem. shipped and fixed in a jiffy, and all i had to pay was one way shipping to vermont.
I own a Bryston 4B-ST, and have a couple of suggestions for you:
1. Check the switch on the rear panel for the "Bridged/Individual" mode to be sure that you have not accidentally set it to "bridged" (which would cause the amp to operate in only one channel).
2. Check the fuses (under the panel next to the power cord connection).
3. If neither of the two steps above result in a "fix", then send an E-mail to James Tanner at Bryston. Go to Bryston's home page (www.bryston.ca), and at the bottom of the home page there is a link for technical questions. Tanner is terrific about providing fast answers to E-mails he receives.

If your amp does have an actual electrical problem, you can remove the non-functioning amplifier module for the dead channel and send only that module to Bryston for replacement or repair. Bryston will sometimes send you the replacement immediately while the module from your amp is in transit to Bryston's U.S. repair facility (in Vermont, as I recall).
Sounds like a plan. Many thanks. The thing's not set to bridged (yes, it was the first thing I checked, all the while asking myself how, sitting in a room by itself, it could have switched itself to bridged but checking it none the less). I'll have to have a gander at those fuses when I get home. I've corresponded with James Tanner before and there's no doubt about it, he's one of the good ones.
If a check of the fuses yields nothing, then I would try swapping the input leads from the preamp between channels, to make sure it's not an upstream problem. I would also swap your speaker leads to make sure the speaker on the dead channel didn't suffer damage, or that the speaker itself is not the problem. Good luck!