[larevoj]

Is there anyone here can confirm the ratings of the Caps in 4BSST2?? 

[srb]

Here is a photo of a 4BSST2 4BSST showing one of the 5600uF 100V 105°C power supply capacitors.
 
Steve
 

[vegasdave]

I hate to say this, but the sticker says SST not SST2. But, they're probably the same caps, true?

[srb]

I hate to say this, but the sticker says SST not SST2. But, they're probably the same caps, true?

I had found two pics of amps that were supposedly "squared" models, and neither has the squared nomenclature on the sticker, so maybe it isn't.  Or perhaps it is reflected somewhere in the other numbers?  Maybe someone with a "squared" can take a look at their rear panel sticker?
 
At any rate, I would be surprised to find any semi-recent Bryston amp that didn't have 105°C caps.  If I'm looking at an amplifier and have the ability to look inside, I probably wouldn't buy it if it had 85°C caps.  Given the same operating enviornment, they're just not going to be as long lasting as the higher temperature spec caps.
 
Remember, the caps will gradually degrade over time, and you might not notice the slow decline in sound quality over a long period.  That's why many people who have re-capped older but still "working" amps often have a relevatory OMG at the improved sound and dynamics.
 
Steve

[Diamond Dog]

Hi Steve: Just checked my amps and they are indeed marked as "SST2" on the back panel sticker.

D.D.

[vegasdave]

I had found two pics of amps that were supposedly "squared" models, and neither has the squared nomenclature on the sticker, so maybe it isn't.  Or perhaps it is reflected somewhere in the other numbers?  Maybe someone with a "squared" can take a look at their rear panel sticker?
 
At any rate, I would be surprised to find any semi-recent Bryston amp that didn't have 105°C caps.  If I'm looking at an amplifier and have the ability to look inside, I probably wouldn't buy it if it had 85°C caps.  Given the same operating enviornment, they're just not going to be as long lasting as the higher temperature spec caps.
 
Remember, the caps will gradually degrade over time, and you might not notice the slow decline in sound quality over a long period.  That's why many people who have re-capped older but still "working" amps often have a relevatory OMG at the improved sound and dynamics.
 
Steve

Ok, cool. No problem. Thanks for the explanation.

[larevoj]

There are still too many factors in play (examples are rate of heat dissipation from source, thermal resistance of selected heatsink, etc.) and are beyond my knowledge to give an objective answer. I suppose James or the technical folks at Bryston can help to shed some light here...

Perhaps the best prove of reliability is to ask if anyone here actually leave their 4BSST2 or any Bryston amplifiers on (green led/s on the front lights up) 24/7 and for how long (years) under what kind of environment specifically room temperature. 

[Moon Doggy]

This thread is such a straw man. ALL Amps sound the best when they have been on for a long time (days)!

[Elizabeth]

Checked my 4B-SST2 and the back sticker has 'SST2" on it.
The SST2 has a different power button on the front besides the sticker on the back
As for long term. I had a Forte 4a amp i bought new when it came out. That amp ran hot! (Class "A" operation) I could just barely keep my hand on the fins and not get burned. I kept that amp on 24/7 for most of 17 years, before i bought the Bryston 4B-SST2.
I sold the Forte 4a and the buyer is happy with it.
So 17 years at a much higher temp than my Bryston idles at, no problem at all. It was a great little amp.
IMO 'theory' always sounds good... Practical experience is better.

[James Tanner]

There are still too many factors in play (examples are rate of heat dissipation from source, thermal resistance of selected heatsink, etc.) and are beyond my knowledge to give an objective answer. I suppose James or the technical folks at Bryston can help to shed some light here...

Perhaps the best prove of reliability is to ask if anyone here actually leave their 4BSST2 or any Bryston amplifiers on (green led/s on the front lights up) 24/7 and for how long (years) under what kind of environment specifically room temperature. 

About 12 years ago I was doing a recording with Oscar Peterson and Ray Brown and Jack Renner from Telarc in a recording studio in Toronto called Eastern Sound.

While I was sitting in one studio the owner of the studio came in and asked if I was with Bryston. I said yes... and he said... "please follow me". Gee's I thought what have I screwed up now!  He takes me into another studio and there behind a glass enclosure are 6 Bryston amplifiers with green lights a glowing ... which power the main monitoring speakers in that studio. He says to me "how long do you think those amps have been on?"  I say - a while I hope without any issues.

He says - "18 years"!

I smile.

james

[larevoj]

About 12 years ago I was doing a recording with Oscar Peterson and Ray Brown and Jack Renner from Telarc in a recording studio in Toronto called Eastern Sound.

While I was sitting in one studio the owner of the studio came in and asked if I was with Bryston. I said yes... and he said... "please follow me". Gee's I thought what have I screwed up now!  He takes me into another studio and there behind a glass enclosure are 6 Bryston amplifiers with green lights a glowing ... which power the main monitoring speakers in that studio. He says to me "how long do you think those amps have been on?"  I say - a while I hope without any issues.

He says - "18 years"!

I smile.

james

Eighteen bloody long years!!! 

[SoundGame]

About 12 years ago I was doing a recording with Oscar Peterson and Ray Brown and Jack Renner from Telarc in a recording studio in Toronto called Eastern Sound.

While I was sitting in one studio the owner of the studio came in and asked if I was with Bryston. I said yes... and he said... "please follow me". Gee's I thought what have I screwed up now!  He takes me into another studio and there behind a glass enclosure are 6 Bryston amplifiers with green lights a glowing ... which power the main monitoring speakers in that studio. He says to me "how long do you think those amps have been on?"  I say - a while I hope without any issues.

He says - "18 years"!

I smile.

james

I just read this and thought it was very neat, especially with James' reference to Eastern Sound (this is taken from SoundStage' Bryston Factory Tour article of 2006):

"I was surprised to learn that when Bryston started in 1962, the company was based in the US and had nothing to do with audio. Bryston’s three founders, Tony Bower, Stan Rybb, and John Stoneborough (their last names form the acronym from which Bryston takes its name), made blood-analysis equipment. This continued until 1968, when NASA engineer John Russell, Sr. bought the company....Once his son Chris had finished college, John hired him to work for Bryston, and Chris set to work designing the first Bryston amplifier...This amplifier was completed in 1973 and became known as the Pro 3. It boasted 100Wpc, used a dual-mono power supply, and featured high slew rates. Chris brought a prototype of the Pro 3 to a recording studio in Toronto, Eastern Sound, for an amplifier shoot-out. Chris’s amplifier won, and Eastern Sound was so impressed by the prototype that they ordered two production units. Chris immediately set to work building these. At that time the engineer in charge of sound equipment at the studio was Stuart Taylor. Bryston hired him ten years later, and he still works there today."

http://www.soundstagelive.com/factorytours/bryston/

[SoundGame]

Oh, and thought this shot would go with my last post.  From top to bottom - they are:

1B, Pro 3, 4B, 3B, 2B

[vegasdave]

There are still too many factors in play (examples are rate of heat dissipation from source, thermal resistance of selected heatsink, etc.) and are beyond my knowledge to give an objective answer. I suppose James or the technical folks at Bryston can help to shed some light here...

Perhaps the best prove of reliability is to ask if anyone here actually leave their 4BSST2 or any Bryston amplifiers on (green led/s on the front lights up) 24/7 and for how long (years) under what kind of environment specifically room temperature. 

My listening room is always at room temperature regardless of season.

[SoundGame]

Though I made this most on the other thread regarding the 9BSST, I thought it should go here as well - given discussion on heat:

Interestingly enough - I came across this review in Stereophile, where the footnote made specific mention of the impact of heat on capacitor life.  It states the following: "Footnote 1: Each time a filter capacitor's temperature is lowered by 5 degrees C, its operating life is doubled."

http://www.stereophile.com/solidpoweramps/725

Good reason I guess for keeping your amp cool.

[srb]

The doubling of capacitor life for each 10°C lower temperature seems to be what most capacitor engineers say, including Sam G. Parler Jr., P.E. for Cornell Dubilier in his paper "Deriving Life Multipliers for Electrolytic Capacitors".  http://www.newark.com/pdfs/techarticles/cornell/multipliers.pdf
 
Many of us have had amplifiers for 20 years that are still working and haven't "failed", but I'll repeat myself here and say again that the capacitance slowly decreases over the years.  Most manufacturers will define it as a "failure" if the capacitance has changed on the order of 20% - 30%, even if the capacitor has not shorted or open circuited ("failure" to you and me).
 
Performance however, is not what it once was, but you won't realize it because the capacitance has been gradual diminishing over the years.  So for me personally, I will preserve the "sonic life" of my electrolytics by turning the amplifier off when not in use while saving money and energy in the process and also locating my heat producing components in open rack space rather than enclosed cabinetry.
 
Steve

[Elizabeth]

5C doubles the life, so 10C is four times the lifespan. and 15C is sixteen times the lifespan, and 25C is sixty four  times the lifespan.. and 30C is 128 times.. 35/256 40 512 times So if you had your cap at room temp (20C) instead of at 60C the cap would last over FIVE HUNDRED times longer.... Hmmm. 
So your average cap lasts twenty years..
times five hundred is 10,000 years... Glad we could sort that out.
And the tests to show the cap still happy near 10,000 years of use are...where?
The problem with statistics, and facts out of context.. Theory is fine,as theory goes. Never let the facts get in the way of a great theory....