XMC-1: L/R Main output to Amp Diff Balanced??
Nov 6, 2023 11:10:46 GMT -5
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Post by 405x5 on Nov 6, 2023 11:10:46 GMT -5
When I tried to read about their "dual transformers"... while their description made sense, for the most part, there were a few "odd bits"...
As far as I can tell they have dual POWER SUPPLY transformers.... each with its own power cable.
This makes sense in that you can connect both, to two separate circuits, get more current through the power supply...
This would "enable it to charge or recharge the POWER SUPPLY capacitors more quickly".
And, by lowering the impedance of the power supply, could indeed change the sound of the amplifier (at least slightly).
(And, of course, if you only have one circuit handy, one circuit is presumably adequate for normal use.)
(There seems to be some odd wording in their description that makes it seem somewhat confusing.)
As far as I can determine that amplifier also ALSO has a specific, and somewhat unusual, input requirement.
It can either be run as a stereo amplifier using a pair of unbalanced input connections...
Or it can be run as a fully balanced fully differential monoblock - and, in order to do that, it requires "a real balanced input source".
(It doesn't have an internal unbalanced-to-balanced converter.)
And, yes, the balanced outputs on the XMC-1 are REAL BALANCED OUTPUTS and will fulfill that requirement.
(On any of our gear that has balanced outputs those outputs are "real balanced outputs".)
(But, from what they've described, that really has nothing to do with the dual-transformer "option", which is really basically a power-supply feature.)
Here is a very complete review describing the need for differential balancing with this amp : Positive Feedback Issue 59.
Brief quote:
One 9008A can be used as a stereo amp with single-ended interconnects. However, the manufacturer strongly recommends you use it as a monoblock, with balanced interconnect cables and a balanced input source.
The amp's design is differential balanced: there are two amps inside each monoblock, one for the ON phase; the other for the OFF phase. When used in balanced mono mode, it is a true differential amp. Stereo connection is only available in single-ended mode, where one amp sees the left channel's input… same for the right channel.
The most important thing that I failed to do when first following this thread was to take a close look at the 9008 and what you’re trying to do with it and what you’re pairing with it (XMC1). after seeing the price tag, all my questions have been answered differential or not balanced or unbalanced. This is typical of the kind of thing that happens when we get into exotica land.
