For years (decades?) I've been telling people, You don't have to hear
voices to have an RFI problem, and you don't have to hear hum to have a
On Sun, Jun 22, 2014 at 4:38 PM, Clark Johnsen <[log in to unmask]>
> I admire the industriousness with which you're tackling the situation. But
> I do have some caveats.
> -- Surge suppressors are hardly needed for audio gear and have a bad habit
> of sounding nasty.
> -- Power conditioning too is a fraught subject. I used to use transformers
> myself but found they have a compression effect. My recommendation: Get all
> set up and only then try power conditioners.
> -- If your power arrives at 220/240 it will be split into two legs. Make
> sure that all your audio is taken from one side only, and put your
> computers, refrigerators and AC units on the other.
> On Wed, Jun 18, 2014 at 3:50 PM, Robert Cham <[log in to unmask]> wrote:
>> In my new house, presently under construction, there will be surge
>> suppression on the incoming lines, and power filtering on selected
>> circuits. These include home runs for left an right audio, there will be a
>> separate circuit for digital audio, home theater in the bedroom, and my
>> editing suite. The surge suppression will likely be LEI, haven't decided
>> yet on power filtering, but am leaning toward isolation transformers.
>> Comments are most welcome on this one.
>> It has been my experience that power line garbage and RF noise are the
>> biggest roadblocks to audio quality. I am living in very rural Virginia,
>> at least partially because of this issue. There will be no wireless
>> devices allowed in the house except "dumb" cell phones. I spent all
>> morning today planning cable runs for computer networks. The inverters for
>> my solar electric system were chosen largely on the basis of their low sine
>> wave distortion, considerably lower than power company standards. I looked
>> at going down to DC and regenerating an AC signal for audio systems, but
>> enough is enough, even for a geeky engineers house.
>> The reason for the separate left and right channel power runs id that I
>> have noticed that crosstalk between channels, generally through the power
>> supply, is the biggest enemy of stereo image. Power amplifiers will be
>> mono blocks, and I'm working on preasmps with separate power supplies for
>> each channel, at the very least separate regulators for each channel.
>> Excessive? Of course, but this will be my last house, and infrastructure
>> changes are relatively inexpensive when the wallboard isn't up yet. Now
>> that I'm retired, I will have time to finish audio design projects that
>> have been hanging for for years, at least when I'm not raising grapes,
>> making wine, smoking meats and raising most of our food. It will be nice
>> to know that subtle changes in circuits are not being swamped by incoming
>> power problems
>> Bob Cham
>> Yeah, like having a desktop computer system plugged into the same AC as
>>> your hifi. Move it to another circuit. Providing the sound system with it's
>>> own AC line (or two) straight from the panel can bring hidden vitality to
>>> even a modest hifi. Power matters.
>>>> I suspect that, a lot of the time, mysterious differences in how
>>>> something sounds turn out to be the result of out-of-band garbage making
>>>> its way into the system, either via the signal cables or the wall. We live
>>>> in an RFI jungle nowadays.
>>>> One of the biggest improvements Greg Mackie ever made to the mic
>>>> preamps in his mixers was a simple upgrade in their RF-proofing.