If there is cross-talk, it is inaudible, similar to using a single transformer connected to the same mains wall outlet connected to the same HT supply connected the the guy next door's hi-fi...
I agree with you Ian, if one wants to restore then it means bring back to original, else it is called modification. Same as restoring a vintage E-type Jaguar powering it by a Ford V8🙂
Can't think where I read it, but some people seem to think that it is not always a good idea to power an audio amplifier from a regulated supply - and I guess a SMPS is regulated - because the two can end up interacting in strange ways. I'm sure it's not a universal truth, but intuitively I could imagine it happening. Can stability be guaranteed?
Quad went over to a floating ground configuration that intrinsically offered a level of DC protection and various other benefits in their later amplifiers. This relies on a certain minimum size of smoothing cap I am guessing, so the SMPS would have to be able to cope with a large capacitive load if you wanted to use that rather neat system.
The majority of professional designers would likely agree with that in reference to linear regulators, as although you might clean up a dirty power source that way, its cheaper and much more efficient to do so with adequate amplifier PSRR.
I don't think you get any real benefits with linear regulation other than filtering, yet the ability to have decent current capacity is restricted by bulk and cost. A high peak current regulator is not a cheap or small undertaking and those who imagine you can place huge capacitance after regulators are, of course, not talking about regulation, as we understand it.
SMPS regulation is usually a part of its operation, to the degree of its specification anyway, so I guess we have to consider those qualities together. At least it's a highly efficient and cheap way of doing it, so you may as well have it and perhaps a better peak current capability too.
The best amplifiers have regulated supplies in some form or other and will improve sound quality as the rails are not modulated at all, but the problem is that the power supply becomes far to expensive for commercial reasons.
Last edited:
Quad has had a virtual grounding in all of their amps since I can remember. Most of my designs use a similar virtual ground (cribbed from Quad) and it solves many hum and earth loop problems.
- Status
- Not open for further replies.