Print

Print


Here's an article I think you guys will find interesting: Arthur Kelm, A Well-Grounded Approach to AC Power Problems. Mix, June 2009.

https://dl.dropboxusercontent.com/u/5328200/Studio%20Power_Mix_June_09.pdf


-----Original Message-----
From: Association for Recorded Sound Discussion List [mailto:[log in to unmask]] On Behalf Of Clark Johnsen
Sent: Sunday, June 22, 2014 4:39 PM
To: [log in to unmask]
Subject: Re: [ARSCLIST] Upgrading Audio Systems

Bob,

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.

clark



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.
>>>
>>> Peace,
>>> Paul
>>>
>>>
>> !DSPAM:639,53a1704799759092120145!
>>
>