[KeithA]

Last night I turned on the amp to listen for a while. I turned it on (no content playing, just idling) and went upstairs for 5 minutes to grab a coffee. When I came back down, the right channel indicator was yellow. This is the first time I've ever seen that!

I placed my hand on the right hand side cooling fins and they were really hot to the touch, way more than the left side. I shut the amp down for a while and turned it back on and the amp cut out again. I did this 3 or 4 times and on the last attempt, the amp worked properly and did not thermal down for the rest of the evening. I kept checking the left and right fin temperatures (by touch) for the rest of the evening and they seemed to even out.

I turned the amp on idle this morning to see what would happen again. I noticed that the right hand side of the amp ramped up temperature wise to be really hot to the touch compared to the left hand side. Is this normal? The amp did not thermal down this time, but the right hand side still got pretty hot fairly quickly.

Any ideas what could be causing this?

Cheers

Keith

[James Tanner]

Last night I turned on the amp to listen for a while. I turned it on (no content playing, just idling) and went upstairs for 5 minutes to grab a coffee. When I came back down, the right channel indicator was yellow. This is the first time I've ever seen that!

I placed my hand on the right hand side cooling fins and they were really hot to the touch, way more than the left side. I shut the amp down for a while and turned it back on and the amp cut out again. I did this 3 or 4 times and on the last attempt, the amp worked properly and did not thermal down for the rest of the evening. I kept checking the left and right fin temperatures (by touch) for the rest of the evening and they seemed to even out.

I turned the amp on idle this morning to see what would happen again. I noticed that the right hand side of the amp ramped up temperature wise to be really hot to the touch compared to the left hand side. Is this normal? The amp did not thermal down this time, but the right hand side still got pretty hot fairly quickly.

Any ideas what could be causing this?

Cheers

Keith

Hi Keith

The bias is self adjusting when you first turn it on  - sounds like it is being over biased on start up. Shoul be adjusted.

No damage can occur.

James

[KeithA]

Hi Keith

The bias is self adjusting when you first turn it on  - sounds like it is being over biased on start up. Shoul be adjusted.

James

James,

Is this something that I would have to send the amp into Mike for? I'm not sure my local dealer would be really familiar with that (St. John's, NL).

Keith

[KeithA]

James,

Is this something that I would have to send the amp into Mike for? I'm not sure my local dealer would be really familiar with that (St. John's, NL).

Keith

Actually found the biasing instructions online. I may have a look-see myself.

Keith

[James Tanner]

Actually found the biasing instructions online. I may have a look-see myself.

Keith

Sounds good - give Mike a call on Tuesday if you need help.

James

[KeithA]

Sounds good - give Mike a call on Tuesday if you need help.

James

Sure thing. I thought it may be bias-related, buy figured I'd check here first.

I've built tube guitar amps so I know the dangers that lurk under the hood!At a minimum, I'll take the bias readings. If something is still amiss, I'll call Mike and maybe have the amp sent to you guys for a look-see and maybe even get whatever 'tweaks' are available as well while she is there. However, I'd like to avoid that, if possible, due to shipping distance.

Thanks for your help.

Cheers

Keith

[KeithA]

Just an update. I removed the amp from the system to check the bias. The bias is spot on at .0062v across each of the test points and the fins of the amp are no longer heating up like last night and earlier this morning.

The only thing different from before is that the amplifier is plugged directly into the wall as opposed to the Torus and the speakers are not hooked up to the amp (but even though the speakers were hooked up last night, there was no program material playing).

Weird? Could it be that something weird has happened inside the speakers (crossover, etc?) that are causing something funky to happen, load wise, even when the system is at idle? I'll hook it back up again to see what happens.

Keith

[BrysTony]

Weird? Could it be that something weird has happened inside the speakers (crossover, etc?) that are causing something funky to happen, load wise, even when the system is at idle? I'll hook it back up again to see what happens.

Keith

Could be -- swap the speakers to see if the problem moves to the left channel.

Tony

[KeithA]

Could be -- swap the speakers to see if the problem moves to the left channel.

Tony

Lol...that's exactly what I plan to do !

Keith

[KeithA]

James

I ran the amplifier for a couple hours this afternoon and checked the bias every once in a while.

The bias checked out perfect. After letting the amp cool down I restarted it. The right hand side seemed to heat up quicker than the left hand side. However, it never did approach the temperature from last night and this morning. In the end, the amp is working fine again.

I'll just keep an eye on it over the next little while to see what happens. Except for completely disconnecting the amp from the system, the only other thing I did was to blow some dust from inside the chassis when I removed the cover! Maybe that did the trick!

My system has been powered up for 3 hours now at low volume and all appears to be fine. Go figure!

Cheers

Keith

[James Tanner]

James

I ran the amplifier for a couple hours this afternoon and checked the bias every once in a while.

The bias checked out perfect. After letting the amp cool down I restarted it. The right hand side seemed to heat up quicker than the left hand side. However, it never did approach the temperature from last night and this morning. In the end, the amp is working fine again.

I'll just keep an eye on it over the next little while to see what happens. Except for completely disconnecting the amp from the system, the only other thing I did was to blow some dust from inside the chassis when I removed the cover! Maybe that did the trick!

My system has been powered up for 3 hours now at low volume and all appears to be fine. Go figure!

Cheers

Keith

Ok good news - keep me tuned in.

james

[Superfly2013]

hi,

i actually experienced almost the same thing. I have a 4bsst2 amp, 1 month ago, i turned it on for a session of listening. After the third song (about 10mins), my amp automatically shut down. I went to see what happened and found out that the right side heatsink is very hot but the left isn't.  i decided not to turn it on again. Ind sent it to our Bryston dealer the day after, however when they tested it, it was normal, they tested it for a few days and the problem never came back, i got the amp and up to now its been normal.

still wondering what happened that time.

[KeithA]

Hmmm, powered the amp on tonight and after about 5 minutes at idle, I could not keep my hand on the right heat sink.

The amp did not thermal down this time, but got extremely hot (eventually settling down). Something seems amiss for sure.

I'll try it the next two days after work as well. If the amp continues to get extremely hot on startup, I'll email/call Mike and perhaps ship the amp up for a checkup.

Keith

[brucek]

In January, while listening to music, the left channel heat sink of my 3BST got very hot (after working flawless for 12 years). I heard a metal pinging sound from the amp and took a temperature of the heat sinks with my laser thermometer and the right channel was 35 degrees C and the left channel was 75 degrees C - very hot. I turned it off and checked the speaker cables and all measured fine with a meter. I measured the temperature of my 4BST and 5BST amps and all heat sinks were about 35 degrees.

The next day I tried the 3BST amp again and for about an hour both heat sinks measured normal temperature of 35 degrees, but then for no reason the left channel got very hot again and blew the main fuse.

I decided to shut it off immediately and decided not to try a new fuse.

I sent it in and they fixed it all up and that's been the end of my trouble. Nice to have a 20 year warranty.

I suggest you send your amp in for repair.

brucek

[Phil A]

hi,

i actually experienced almost the same thing. I have a 4bsst2 amp, 1 month ago, i turned it on for a session of listening. After the third song (about 10mins), my amp automatically shut down. I went to see what happened and found out that the right side heatsink is very hot but the left isn't.  i decided not to turn it on again. Ind sent it to our Bryston dealer the day after, however when they tested it, it was normal, they tested it for a few days and the problem never came back, i got the amp and up to now its been normal.

still wondering what happened that time.

I had the issue with my 14BSST and it was sent to Bryston twice over the years.  Once early on and once before I sold it.  I was told both times there is nothing wrong even though the right channel shut down with old speakers and would very hot (burn your hand) with newer ones.  It just did not like the impedance of my speakers.  Before I got the 14BSST, I had a 6BSST on the front channels (with the speakers that shut down the right channel) and had no problems over several months.  The 14BSST sounded better though.  I had the 15 amp version of the 14BSST as I did not have a 20 amp circuit with 12 gauge wire for the 20 amp version of the 14BSST which was supposed to be better with lower impedance loads.  So I guess there was a reason they made a 20 amp version.

[KeithA]

In January, while listening to music, the left channel heat sink of my 3BST got very hot (after working flawless for 12 years). I heard a metal pinging sound from the amp and took a temperature of the heat sinks with my laser thermometer and the right channel was 35 degrees C and the left channel was 75 degrees C - very hot. I turned it off and checked the speaker cables and all measured fine with a meter. I measured the temperature of my 4BST and 5BST amps and all heat sinks were about 35 degrees.

The next day I tried the 3BST amp again and for about an hour both heat sinks measured normal temperature of 35 degrees, but then for no reason the left channel got very hot again and blew the main fuse.

I decided to shut it off immediately and decided not to try a new fuse.

I sent it in and they fixed it all up and that's been the end of my trouble. Nice to have a 20 year warranty.

I suggest you send your amp in for repair.

brucek

Yep, I think that's what I'll do.

It funny, since this happened this weekend, I thought back and remembered that last week I has the system on very low with Netflix running in the background and the right channel seemed to fizzle out and then come back after 5 to 10 seconds. I just assumed it was a glitch with Netflix. However, now I'm wondering if something happened to the right channel of the amp? maybe...maybe not.

This is the first little hiccup in the 10 years that I've owned all my Bryston gear. No biggie...if there is something wrong we'll get it worked out, for sure!

Keith

[KeithA]

I had the issue with my 14BSST and it was sent to Bryston twice over the years.  Once early on and once before I sold it.  I was told both times there is nothing wrong even though the right channel shut down with old speakers and would very hot (burn your hand) with newer ones.  It just did not like the impedance of my speakers.  Before I got the 14BSST, I had a 6BSST on the front channels (with the speakers that shut down the right channel) and had no problems over several months.  The 14BSST sounded better though.  I had the 15 amp version of the 14BSST as I did not have a 20 amp circuit with 12 gauge wire for the 20 amp version of the 14BSST which was supposed to be better with lower impedance loads.  So I guess there was a reason they made a 20 amp version.

Yeah Phil, it's weird.

In my case, though, it's happening at idle and seems to be not happening all the time. Could be some component close to failing, I guess.

I"ll post what happens over the next couple days and if/when I ship off the Bryston, I'll update as well.

I'd hate to think I'm just imagining this!

Keith

[hawkeye99]

I had a pair of interconnects between B6 and 2B SST2 that caused the 2B to overheat. They overheated an older 2B also. Changed interconnects and the problem was solved. I'm still using the interconnect elsewhere in the system with no issues.

[KeithA]

We can rule out the interconnects, etc, now. Yesterday I tested the amp out of the system a couple times. The first time the amp powered up perfectly. However, a couple hours later I tried it again and the right side ramped up to untouchable in minutes.

So, I'm going to send the amp in for Bryston to have a look at.

Keith