[john1970]

To all Bryston owners,

I am going to purchase a Bryston amp (either the 14 B SST or 4B SST) and ideally I would like to purchase the 14 B SST for the extra headroom. 

However, I am very concerned with the 14 B SST heating issues.  A few owners on various forums have stated the the amp runs extremely hot.

During the Stereophile review ( it was noted that):

"With the Bryston 14B-SST, however, not only was its chassis too hot to touch after just 20 minutes of driving 200Wpc into 8 ohms, it turned itself off after 25 minutes. While this IHF-recommended test is very much the worst case for a design with a class-B output stage and it is unlikely the 14B-SST will get this hot under normal use with music, it does suggest that the amplifier's heatsinking is underspecified for continuous use at high levels."

Given this issue is it best to go with the 4B SST.  I would feel really stupid purchasing an amp for ~$6K only to see that it turns itself off during loud passages.  Moreover, as we all know heat kills componets and all else being equal a cooler amp will last longer.

Any feedback will be appreciated. 

Thank you,

John

[Phil A]

John, what will the 14B be driving and how big is your room and how loud do you like to listen?  I got a 6BSST very lightly used and then got a 14BSST the same way a bit later a couple of yrs. back.  They drive Thiel 7.2s which are not the easiest load in the world and the room is huge.  I ended up building a customer stand with fans (5 of them) for any extended listening or for a heavy duty movie soundtrack.

[Bob Reynolds]

Hi John,

I recall that Stereophile review and was disappointed by JA's findings regarding the amount of heat sinking. Remember that this was a constant 200watts -- music does not behave that way.

I own the 7B-SST monoblocks, which drive 4 ohm speakers in a 17 x 17 x 12 foot room. Even after a 2 hour action adventure DVD you can barely tell the amps are on they run so cool.

I would not let that be a determining factor in your decision unless you plan on putting the amp in a closet or cabinet.

-- Bob

[john1970]

To all,

The amp would be driving a pair of VMPS RM40 loudspeakers (specs: 89 dB/1w/1m, max RMS 500W) in a medium sized room 15' x 25' x 8'.  I never listen to music louder than 100 dB peaks and normal extended listening is performed with 90 dB peaks.  I like keeping my hearing. 

Thank you,

John

[Adz523]

The late Jim Piscitello, a former member on this board, had for a long time the same setup you are considering - RM40s being driven by a 14BSST.  He loved it, no heat sink issues at all or other problems that I know of.   I was very fortunate to listen to it as well and you would not be disappointed.

[dan_lo]

To all,

The amp would be driving a pair of VMPS RM40 loudspeakers (specs: 89 dB/1w/1m, max RMS 500W) in a medium sized room 15' x 25' x 8'.  I never listen to music louder than 100 dB peaks and normal extended listening is performed with 90 dB peaks.  I like keeping my hearing. 

Thank you,

John

Just to ease your mind.
The test you are talking about is not realistic. In your system it means your speakers will be driven to 112 DB/1m  on *avarage* (that's what 200W will get you),  which means that on peaks it will reach close to 135dB/1m - truly ridiculous.

[Angelo62]

My 7B ST's drive the 81 dB MBL 101 D loudspeakers.
They run very hot after a couple of hours of heavy duty (I saw them clipping more than once) but they never turned themselves off.

Angelo Jasparro
www.videohifi.com

[Phil A]

I would not think you would have much of an issue.  My room is about 16x20 with a 19 ft. ceiling and opens into other spaces (so we're likely talking somewhere around 10,000 cubic ft.).  I probably listen a bit louder and my speakers are only 86db and much rougher to drive.  The 6BSST, when I used it for a few months on the front channels had no issues driving my speakers so it is the higher class A output of the 14BSST and the impedence of my speakers that cause the problem.

[john1970]

Phil,

Thanks for the response.  That is what I gathered as well once I found out that the 14B SST was class A upto 25 watts.  To prevent over heating I am going to purchase the 4B SST instead.  Its output will be more than enough for my needs and it cost ~1/2 as much.

Thank you,

John

[Phil A]

Glad to have been of help.  The bass response and bass control is better on the 14BSST and it sounds a bit more effortless (I had a friend over when I hooked up the 14BSST for the 1st time and I since my Rel subs have a high level input in addition to the low level one - I turned them off when I connected speaker leads to the amp - he could not believe I turned the subs off - thought they were on with the 14BSST - until I turned them back on a minute later and he noticed the bass got a bit better).  I would think on a large amt. of recordings and with a decent amt. of speakers (Thiel 7.2s which I have in the main are the poster child for needing everything in front of them top notch - they don't forgive things very easily - I have some recordings I can listen to on one of my other systems - bedroom or basement - that the 7.2s don't do justice to) many would be hard pressed to tell much difference depending on listening preferences and tastes.

[john1970]

Phil,

From what I have read on this and other forums the 14B SST does provide a improvement in bass over the 4B SST.  However, I am sure that the difference between my NAD C372 (150 W/channel) and the 4B SST (500 W/channel) will be an even larger change. 

Thank you again,

John

[Mike-48]

Phil,

Maybe you've already made your decision, but I thought I'd throw in my 2c worth.  I have two 14B's running in my listening room now.  Yes, they get a bit warm after a while, but they run much cooler than many other amps.  We live in the US South (North Carolina), so heat generation is a consideration.  I have never owned tube gear for that reason.  To sum up, the 14B is a great amp, and I doubt you'll find many competitors that run substantially cooler.

Regards,
...Mike

[Phil A]

?  I already have a 14BSST and a 6BSST.  Drive Thiel 7.2s with them in a very large room w/o the custom stand I built with fans on certain musical things and it shuts down after 20-25 minutes.  On demanding movies it shuts down as well from the heat.  I've owned other amps.  The 6BSST was on the front channels for a bit and no heat problems.  Many moons ago I owned a 4BST and had them on the front channels.  It never got hot but on really demanding stuff it might for split second have the LED red or yellow as the speakers demand a lot.  Had Proceed amps (HPA) on the front too with no heat issues.  If I had 12 ga. wire running to my electrical box, I would have opted for the 20 amp version and that might have been better.  I don't need the fans on all the time.  It does get very hot to the touch and you can burn yourself.  Many moons ago I had a Dynaco ST-70 tube amp on an old pr. of speakers and you could fry eggs on that.

[Mike-48]

Phil,

I understand the "?".  My reply should have been addressed to the original poster, John1970, not you.

Maybe your 14B should be checked out by Bryston service?  Or maybe I just don't put the same demands on mine as you do.

Happy listening!

Regards,
...Mike

[Phil A]

Mike - I've spoke to them on several occasions.  I also spoke to the guy I bought it (the 14BSST) from who had Thiel 6s (I have 7.2s).  In a room as large as mine with those speakers it is the way it is.  I have a 20 amp separate circuit (I asked for a separate circuit when the house was built) but I did not specify 20 amp or 15 amp and they put a 20 amp circuit but just ran std. 14 ga. wire.  If they had used 12, the 20 amp version of the 14BSST would have been purchased (I checked with Bryston before I made the purchase - they make the 20 amp version of the amp for speakers with lower impedences).  Thiels do some things great.  One thing is that that are not easy to drive with certain amps.  Many times I don't have the fans on and they are barely audible when they are on.  I've learned what the combo can and can't do together.