Hello everyone, I have just registered here, having recently bought a Bartok Apex. Needless to say, I am delighted with it.
And I also have a question, about how best to deal with high mains voltage, which I might as well go ahead and ask right now. I am UK-based. As some of you will know, mains voltage here is 230V with -6% / +10% tolerance — so potentially (pun intended) up to 253V. By chance, having recently disconnected, moved and reconnected my hifi system (to allow for installation of a dedicated mains circuit), I noticed that the amplifiers in my ATC SCM50 active loudspeakers are humming slightly. Quite faintly — I need to either lean over the ’speakers or kneel behind them to hear it clearly — but it is always present. It turns out that, over several days, our mains voltage has ranged between 244 and 251V. So I then tried switching to our backup supply (solar PV + batteries), which runs at precisely 230V when fully disconnected from the mains. No hum at all.
Now, I accept that this is not conclusive proof that the hum is due to the mains voltage being appreciably higher than 230V. It’s entirely possible that it is being caused by something else, such as DC offset (which might plausibly not have been present when I was powering the system from solar panels via the inverter). Nonetheless, it seems to me conceivable that mains voltage above 244V could be causing the power amps’ transformers to saturate and, as a consequence, hum slightly (I intend calling ATC to ask if this might be so).
So I would be very interested to hear about any forms of power optimisation that includes voltage regulation being used in conjunction with dCS equipment.
(There are several good threads here about power conditioning in general that I have read with interest, but I am asking more specifically about devices whose capabilities include voltage regulation.)
I might add that I have always been rather sceptical (perhaps naively so) about mains power conditioners and regenerators — unless there is an identifiable problem, and humming power amps may qualify, I think. There is clearly a range of options that I might explore, including Torus and PS Audio products (noting what dCS recommend concerning power regeneration; I could, if necessary, use some form of regulation on the ‘speakers only), but there are also voltage optimisation solutions that are not specifically hifi-oriented. I have also posted a similar question on a Linn forum, and did receive a couple of useful suggestions about such devices — but I’d particularly like to hear about experiences with dCS products, too, hence my post here. I will also speak to the power distribution company, but they may decline to do anything so long as the voltage is within tolerance (which it is, just).
Any thoughts or experiences that you could share would be appreciated.
Andrew
