BAT VK 600SE: SE vs. Balanced


I have read in the Positive Feedback Online review(s) of this amp that it was preferable to run it in balanced (XLR IC's) mode. So much so that one should not even consider purchasing the amp if one were to be running it single ended.

Well, my preamp is single-ended only (Herron VTSP-2). How much degradation would there be in running the BAT this way?

Bill
billspecfoc
As I mentioned, all our gain stages are typically differential. In simple terms you can say each stage is its own phase splitter. I know some people think balanced circuit has two independent signal paths, but that is usually not so, there is really just one path which amplifies the difference.

The benefits of such processing are numerous and well known - all high quality electronic instrumentation is built that way - but fall well outside the scope of a small post.

BTW, one common misconception is to believe balanced circuits have lower noise - in fact their OWN noise is always higher, they just reject some of the external noise.

As far as why it is better to give the circuit a true and clean balanced signal even if it can develop one on its own - try this simple exercise. Face your friend and take his hands into yours. Now start turning his body left and right by pushing one hand, pulling the other. Go back and forth and see how easy it is to turn his body. Now drop one hand, and do it with just one. Not as good, heh? :)

Victor
Hello Victor,

Thank you for your reply. Does it mean that you use phase splitter to convert the single ended input signal into two wih equal (to the half of the original signal) and oppose amplitudes? Otherwise, I do not see how your circuitry can work effectively....

Regarding "...Of course ideally you should give it balanced signal for other reasons..."
If my preamp and interconnects are with low, non-audible noise then what other reasons should I consider when choosing between balanced and single ended inputs?

Many thanks - its truly great when designers participate in our forums!!!
Rafael
I was using my VK-75 in SE mode for years and finally switched over xlr. I would have bought a balanced pre years ago if knew how much better it sounds.

Tim
Bob - that is not correct. The internal circuit in that amplifier is fully differential, meaning 100% of it is working at any time. Even when given SE signal it will still process it in differential fashion. Of course ideally you should give it balanced signal for other reasons.

Regards,

Victor Khomenko
Balanced Audio Technology
Very simple answer: BAT (Balanced Aidio Technology) amplifiers are fully balanced. Thus, if you use single ended inpur you will use 50% of its signal path circuitry.

Only you can decide if its worth for you.
Kind of hard to quantify how much "degradation" you might experience in SE mode. BAT equipment is designed to perform its best in balanced mode, hence the name. Lower noise floor for one. Running a BAT amp in SE mode is a compromise, kind of like running economy tires on a Ferrari. The 600SE is a great amp. Get a BAT pre-amp and run it balanced into your amp and you will get the best out of it, for two reasons - synergy and balanced mode. Good luck.