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Questions about Bryston 7B-ST


Hello Guys,

I have just bought a pair of 7B-ST,second hand. I have a few questions in my mind.

1- Amps sometimes produce a weird "zip zip zip" sound when shutting down only on parallel mode. It is not so loud but embrassing. It sounds like an exotic bird. :)

2- Back side and front side transistors are cooler then the middle transistor blocks.

3- It is written 6B on the outrigger boards of all channels.

Are these things normal?

Speakers; B&W M802 S3

Thank you

Best regards

Ozan
ozanhan
pbb
1,140 posts
 
Too bad you are so far and not in Canada like me because Bryston's guarantee is pretty much bulletproof and their service top-notch. Mine is on 24/7, but we do have decent electrical power in Quebec. It is impossible to know from what you indicate how big a difference in temperature there is between transistors, but I would not worry about it. Is there an authorized distributor in your area or at least somewhere in Europe? I would not worry if it works it works. When and if it stops, I would try to get the amps to an authorized repair centre. Good luck.
ozanhan OP
5 posts
 
Hello Audiobugged,

- "The what you call weird, "zip zip zip" sound is normal after you walk a few steps away from the unit." : Ahh! i am happy to hear this. :)

- "The sound kinda sounds like when forwarding the film like a Minox 16mm spy camera. It isn't audioblely disturbing unless your ear in on the unit, I guess?" : I dont know the sound comes from Minox 16mm spy camera when forwarding. I wish i do. Yes, It isn't audibly disturbing, but only one channel makes that sound. That sound comes out from only left speaker. When i switch the amps
left right, it passes to right speaker. It is different from soft, relay click sound.

- "With the 7b-st's running for 6-8 hours steady, they should only be warm to the touch when setting your hand on the top plate. It shouldn't be hot enough to burn you?" : The problem is not the high level of heat. I have just measured using an infrared device after 8 hrs working, result : backside and frontside transistor blocks are 35 celcius, middle blocks show 40 celcius.May this heat difference show a failure of back and front transistors?

Thank you for your attention..

Best regards

Ozan
ozanhan OP
5 posts
 
Hello Pbb,

- "It is impossible to know from what you indicate how big a difference in temperature there is between transistors" : Difference is not so big but may show a failure, am i right?

- "Is there an authorized distributor in your area or at least somewhere in Europe?" : Yes there is an authorized dealer, i have bought it from authorized dealer. They are not so helpful.

Thank you Pbb,

Kind regards
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