Bryston 7B SST


Hi There,

First post of many I hope.

I am using a PS Audio Directstream into a pair of the above monoblocks running into B&W 802 diamonds. The Brystons have a 1v/2v gain setting and a switch for balanced input (XLR) or single ended.

On adding a PS Audio BHK Preamp I noticed a lower relative volume in the right speaker and after checking inputs / isolating components / cutting back to just the Directstream and testing I find that:
On single ended leads, both speakers have equal volume on 1v (1v is louder than 2v)
On single ended leads, both speakers have equal volume on 2vOn XLR, one speaker is louder on 1vOn XLR, one speaker is louder on 2v
So it seems that using XLR, one of the monoblocks is putting out more volume on both of the gain settings relative to the other.

I can run them on single ended leads on the 1v setting to get equal volume, but I can’t help thinking that I’m missing out somehow.

Anyone have any ideas as to what may be wrong or maybe has experienced similar?
Thanks,
Marcus.
astonmartinv8
Something is definitely wrong with the BHK. It could be one of the tubes that is faulty or it could be the Class A output stage. I am guessing the BHK is not providing gain for the "inverted" signal pins on the XLR balanced output. This is likely why one of the amps is quieter when using XLR inputs.
I don’t think it is the BHK as When using the DS as a preamp I had the same issue. It could possibly be the XLR cable (will test this later). 
Went to the local dealer and replaced all the cables. Ooops. I think the issue is in one of the XLRs. It sounds pretty awesome now I have to say.