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
Why do you shut it down?
I agree with Pbb. But also since you are covered by a 20 year warranty issued by a company that is known for their outstanding customer support and service, why don't you call or e-mail Bryston? You can find their contact information at BRYSTON.CA. Their USA service facility is in Vermont.
I am shutting down when not in use, because the mains change everytime in my area. I measure it sometimes 190V sometimes 240V.

I think its guarantie is invalid beacuse it had been opened and serviced by unauthorized service before i buy.

Our salesman says that amp sent to Bryston and they can understand if it was serviced by unauthorized service. if this happened you will pay all the costs including shipping to and from Canada. I am from Turkiye.
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.
Hello Ozanhan,

I have owned 5 Bryston 7B-ST's, and am down to just one after breaking up the H/T set-up. I only powered mine down during thunder storms, or prior to going out of town.

The what you call weird, "zip zip zip" sound is normal after you walk a few steps away from the unit. 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?

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?

I'm sorry I never spent quality time fondling the 7b-st's, to get to know their cold, warm, & hot regions?

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
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