Question about the exact nature of the BP-26's balanced output ( and circuitry )

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Currently using my BP-26, in single ended mode and loving it.

Having said that I am getting ready to switch over to monoblocks that require true differential inputs and have true differential circuitry.

Does the BP-26 put out a differential output?

It was stated that
These amps require an XLR connection where (a) both the hot and cold signals are driven, (b) the hot and cold signals are inverted versions of each other, and (c) the ground connection is actually connected to the source's signal ground. In some cases (c) won't be required. Fortunately, this is how the majority of line-level equipment with XLR outputs is configured today.

The rep want on to say the
Also, to clarify any possible confusion, both the DVA M225 and DVA M750 will produce output with sources that don't meet (a) and (b). However, they won't reap the benefits of the bridged configuration these amps use, and so they won't sound as good nor make the same power.

I had asked, and several forum members said I'd be fine, using the BP-26. However, one member posted something that kind of threw me; he said
James Tanner, in the Bryston circle, can answer your question definitively and is very responsive there. My understanding is that the BP26 is single ended internally and inverts the positive to derive the minus signals in and out. In other words there are not 2 full active signal paths, one plus and one minus, which is required to be true differential.

So, if that is the case then according to the company rep, using a signal that is not a truly differential input will result in amps that
won't sound as good nor make the same power.

Here is a link to my post in that thread.
I am planning on ordering a pair of M750(s), imminently.
I use a Bryston BP-26 preamp. It has a pair of XLR balanced outputs. How would I know if they are true differential outputs? I don't want to compromise the M750's performance.


Looking for some clarity.  :)

James Tanner

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Hi - email Mike on this please -


  • Jr. Member
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Thank you, I just did so. I appreciate you, and your help.



  • Jr. Member
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Well, he must be a busy guy. No answer. Working him too hard, James!


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  • Kevin
Notes: for interconnect systems.
a] 'balanced' inputs or outputs are a sub-set of 'differential' inputs or outputs.
b] there are 3 types of 'balanced' or 'differential' outputs:
1] transformer outputs
2] passive or impedance outputs
3] active or powered outputs.
* * * * * * * * *
a 'differential' input or output is way easier than a 'balanced' one. No precision matching is required.