[good sound]

I just saw an ad on AudiogoN for a Lexicon 512 which I'm sure most everyone here knows is a re-badged bryston 9BST.  In the ad the seller mentions that he had the amp upgraded from ST level to SST level. He then goes on to state that the normal 9BST is notorious for breaking down when hooked up to certain modern pre-amps, but the SST is not. I haven't heard of anything like this before, is there any truth to this or is it just nonsense?

Here is a link to the ad;  http://app.audiogon.com/listings/multi-ch-bryston-lexicon-nt-512-9bst-with-9bsst-upgrades-2013-01-16-amplifiers-01450

[spinner]

 The ST is not upgradable to an SST. according to Bryston

[good sound]

Yes the ST is/was upgradeable to SST but not SST squared or above. There used to be info about the upgrade and what it cost on the Bryston website. If I'm incorrect I'm sure James will chime in. I'm not sure if Bryston still offers this service as a stand alone procedure or not but someone I know recently had a repair done to his 9BST and it was automatically upgraded to SST status at the same time.

Anyhow the important aspect of my post was the claim by this ad poster on AudiogoN that some pre-amps will cause a 9BST to blow it's output transisitors. I don't understand how or why this would happen.

[ragg987]

I have a 9B-ST. Bought 10 years ago, one (or more) channels have failed regularly every 2 years. Like clockwork - currently have a RMA on one channel. About 4 years ago, the transistors of all channels were upgraded to SST variety under warranty as these were supposed to be more reliable. Mine are not showing improved reliability.

Speaking to PMC (UK representative), they receive more 9B in for repair than all other amps combined. Of course this could be because there are 5 channels in this amp, so more likely to fail statistically. My 4B-SST has been fine (8 years old).

Through about 7 of the 10 years of ownership, i have used a Bryston preamp (SP1.7 and now SP3). So unless the Bryston preamps are in the "notorious for causing breakdown" this seems unlikely? Speculation on my part.

Note - relating my experience with my 9B, may not apply to other amps. Thanking the 20 year warranty, though still have the hassle of returning channels for repair regularly.

[Laundrew]

Could this be an issue with respect to overheating with all these modules in close quarters? Is cooling passive or is there a cooling fan?

Be well...

[JeffO]

I also have a 9B ST bought 10 years ago.  The only problem I have had is when I shorted a speaker connection by putting the speaker spike through the wire.     Replaced the wire and all was well. 

I have not heard of any issues with them breaking down when hooked up to certain preamps.  I have used a denon reciever, SP1.7 and SP3 as preamps

[spinner]

 Seems to me the upgrade for an ST wasn't possible because of different layout. James is it or not?. If so what can be done to an ST to(4B)  to refine it ?   

[ragg987]

Could this be an issue with respect to overheating with all these modules in close quarters? Is cooling passive or is there a cooling fan?

Passive cooling - each module has cooling fins with large circulation holes above and below, plus the case has fins on the sides. The last time the module blew, it was at switch-on, so do not think it is heat related. My amp seems pretty cool under use - I tend not to push it too hard, and i only use 4 of the 5 channels.

[Laundrew]

Passive cooling - each module has cooling fins with large circulation holes above and below, plus the case has fins on the sides. The last time the module blew, it was at switch-on, so do not think it is heat related. My amp seems pretty cool under use - I tend not to push it too hard, and i only use 4 of the 5 channels.

Thank you, I was curious as sometimes amplifiers can generate a great deal of heat.

Be well...

[good sound]

Seems to me the upgrade for an ST wasn't possible because of different layout. James is it or not?. If so what can be done to an ST to(4B)  to refine it ?   

Hopefully James will reply, but even if he does not, I can assure you that at one time the upgrade was available and Bryston advertised it on their website. I have seen it more than once. The cost was $200US per channel or $1,000US for all five channels. I know this because I have owned a 9BST for almost 14 years now and I wanted to have the upgrade performed, but wasn't in a position to justify the outlay of cash for it. I am not sure if Bryston still offers this upgrade, although I don't see any reason why they wouldn't, even if they don't advertise it on the website anymore. I understand that you cannot have an ST series amp upgraded to SST squared however because the entire archetecture of the squared series is completely different.

By the way in fourteen years the only problem I have ever had with my 9B was the malfunction of two of the front panel clipping indicator lights. This malfunction happened less than two years after I bought the amp and of course Bryston replaced them very quickly and free of charge. My 9B is powered on 24/7 and gets a minimum of six to eight hours of use a day, every day.

[spinner]

 I think I was referring to the 4 and 3 BST amps. my mistake

[servingko]

I have a 9B-ST that has had the output transistors upgraded to the SST devices.  It isn't exactly the same as a 9B-SST in terms of circuitry, but sound wise it is very close if not essentially equal.  I had a 9B-SST at the same time and decided to keep the converted one and sell the "real" SST. 

As I recall, the primary difference was a soft membrane switch with soft start circuitry, a slightly different grounding protocol, and the SST output devices.  In terms of sound quality differences I would say that everything else in your audio chain will have a larger impact than the differences between the two amp topologies of a 9B upgraded with SST devices and a 9B-SST.  I would go so far to say that in a double blind test you wouldn't be able to tell the difference.

I believe the Lexicon version of the 9B is the same as the Bryston 9B, but the other models of Lexicons had more in common with the NRB series of Bryston amps.  It has been at least ten years since I had this conversation with Bryston concerning the Lexicon amps and may have missed something, perhaps someone else can chime I as well.

[redbook]

   yes that is most likely

[Stu Pitt]

Like servingko said, I thought most, if not all Lexicons were NRB series stuff and not ST.  Perhaps the last Lexicons were. 

As to ST to SST, I had my B60 upgraded from ST to SST.  A very big improvement in my room/system/etc.  easily worth the money I paid for it.  Most 'upgrades' you see advertised are nothing more than tradeoffs - better bass at the expense of highs, etc. - this was one of the few across the board improvements I've had in audio.
Your results may vary. 

[ctviggen]

I have a Lexicon NT512, and my second channel just died.  I'm down to three channels, which sucks, considering I need four. 

Anyone know about how much it will cost to repair a channel?

[good sound]

I have a Lexicon NT512, and my second channel just died.  I'm down to three channels, which sucks, considering I need four. 

Anyone know about how much it will cost to repair a channel?

I take it that the Lexicon amps don't have the same warranty as the Bryston counterpart?

[JeffO]

I have a Lexicon NT512, and my second channel just died.  I'm down to three channels, which sucks, considering I need four. 

Anyone know about how much it will cost to repair a channel?

The Lexicon came with a 5 year warranty not the same as the Bryston counterpart.  Send Mike at Bryston an email for an estimate. 

[ctviggen]

The Lexicon came with a 5 year warranty not the same as the Bryston counterpart.  Send Mike at Bryston an email for an estimate.

Thank you.  Is it just Mike @ Bryston.com?  Unless it's relatively inexpensive to fix, I'll probably just toss my Lexicon, as I can get an outlaw 5 channel amp for $1,500 U.S.   Since I'm using these for surround or family room channels and not true HT/2-channel, I'm not too particular about the quality.

[srb]

Is it just Mike @ Bryston.com?

mpickett at bryston.com