Power conditioning for computer audio


What are the best types of power conditioners/regenerators for PC audio?

I was about to buy a PS Audio regenerator but then read that these devices don't do anything about the high-frequency noise put back into the line by computers and digital sources. So I'm not so sure.

My digital equipment is a Mac Mini and Audio Note & MiniMax DACs. (And also a Sony 5400.)
paulfolbrecht
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Excellent suggestion by Elizabeth. Fair-Rite is a leading ferrite manufacturer. I suspect that one of their "Round Cable Snap-Its" would be suitable, chosen to fit the particular cable diameter. Hopefully one of the distributors they list, such as Mouser, Newark, or Arrow, sells them in small quantities.

This Fair-Rite paper will tell you more than you will want to know about these things.

Happy holidays!
-- Al
Of course, if you stream wirelessly to a network player, it may not matter. Flame away!!!
Thanks both of you for that suggestion. Almarg, it seems there is no way to order direct from them, at least from the web site. I've written them about a direct order. I will look for AudioQuest too.

So, does improvement from these things typically fall into the "I think I hear something" category or the "there is a definite improvement" category?

I'd thought I'd heard it all and was not aware of these things.
Newark.com does sell to individuals in any quantity you want. Their ordering process is a little complex to set up the first time but the selection is vast and the ferrites are very reasonably priced.
Hi Paul,

I checked the site of one of the distributors I mentioned, Mouser Electronics, and you can order from them in quantities as small as 1.

Just enter the Fair-Rite part number into the search box near the top of Mouser's home page. For instance, part number 0431167281 returns this, indicating 17,520 in stock, with a minimum order of 1 piece, costing $2.64. Looks like they'll add on about $7 for shipping of a 1 pound parcel.
So, does improvement from these things typically fall into the "I think I hear something" category or the "there is a definite improvement" category?
I can't really say, as I haven't gotten into computer-based audio, but the technical rationale strikes me as plausible, and the cost is minimal, so my instinct would be to just do it, as a matter of good practice.

Happy holidays, and best for 2011!

-- Al
Barking up the wrong tree, digital out from your MAC doesn't care about internal noise. Your MAC would be malfunctioning if 1's and 0's weren't being read correctly inside the case.
But your external D/A and analog equipment does care about how clean its power source is... ghost signals from other equipment power draws can reduce your tranparency during and after analog conversion.
Davide256, note that the question concerned "high-frequency noise put back into the line by computers and digital sources," so the wrong tree was not being barked up.

Regards,
-- Al
Paul - you must be very careful about where you use ferrites. They can definitely inhibit dynamic current flow to a DAC for instance. If you are using a sound card in a desktop PC, the ferrites may add significantly to the jitter by making the power supply sluggish.

IMO, these are only useful for protection of a computer against line voltage fluctuations. Keep them away from the audio parts.

Steve N.
Empirical Audio
If you are using a sound card in a desktop PC, the ferrites may add significantly to the jitter by making the power supply sluggish.
Hi Steve,

Could you explain why that would be so?

I would expect, given that we are talking about a digital output of the computer (as opposed to an output whose current demands may fluctuate widely) that capacitive energy storage and decoupling on the sound card, and perhaps the motherboard as well, would isolate the sound card circuits from any power supply sluggishness. If a lot of bits are toggling at once in parts of the circuit, then yes there may be a sudden spike in current demand for perhaps a few nanoseconds, but it seems to me that assuring that demand is met during those few nanoseconds is the responsibility of capacitors on the card, not the power supply.

And I would also expect that by far the greatest demands on the power supply in terms of dynamics would be due to the cpu, its associated chipset, and the video card, none of which would be heavily taxed in an audio application.

Thanks, and happy holidays!

-- Al
Hi Guys:

While snowed in today, I was surfing around the net and came across this AC regeneration product from PurePower. It looks like the product is used to clean up chaff from power utility lines. Can someone discuss whether and how so called Power Gremlins (see attached URL link) affect sound quality from stereo gear.

Does it matter if the gear is SS or tube?

What impact (if any) does a regulated power supply in a piece of equipment have on the quality of the unit's internal current?

BTW, the PurePower AC regenerators are not cheap!! See the attached URL.

http://www.purepoweraps.com/Top5.htm
Bifwynne, you might find this thread and this thread to be of interest.
While snowed in today, I was surfing around the net and came across this AC regeneration product from PurePower. It looks like the product is used to clean up chaff from power utility lines. Can someone discuss whether and how so called Power Gremlins (see attached URL link) affect sound quality from stereo gear. Does it matter if the gear is SS or tube? What impact (if any) does a regulated power supply in a piece of equipment have on the quality of the unit's internal current?
From a technical standpoint I don't think it's possible to generalize or predict the effects of a power regenerator or a power conditioner on any given system. There are far too many variables and unknowns involved. Just to cite one small example, rfi may to some degree bypass the power supply, couple into arbitrary internal circuit points that are in the signal path, and intermodulate with the signal resulting in unpredictable effects at frequencies that are audible.

That lack of predictability is unfortunate because, as you point out, these things can be quite expensive.

Regards,
-- Al
Thanks Almarg. The second thread was right on point!

If power Gremlins are really finding their way into the final output that goes to a speaker, from a layman's point of view, that looks like pure distortion. I take your point about rf getting in the middle, but wouldn't that always be the case. It would seem that power-line Gremlins just crap up the signal even more?

I'm still looking for an answer from the forum, in layman's terms, as to whether it matter if the gear is SS or tube? And, what impact (if any) does a regulated power supply in a piece of equipment have on the quality of the unit's internal current? IOW, does an electronic power supply in a way also act like a power regenerator??
"Could you explain why that would be so?

I would expect, given that we are talking about a digital output of the computer (as opposed to an output whose current demands may fluctuate widely) that capacitive energy storage and decoupling on the sound card, and perhaps the motherboard as well, would isolate the sound card circuits from any power supply sluggishness."

Sorry, but there are no voltage regulators out there that reject input voltage variations like this, even the best ones. They are all imperfect. Even lots of power decoupling will not do it. Regulators all have finite response times, so regulating large current transients is a tall order too. All of these things are helpful, but still imperfect.

When it comes to generating a low-jitter digital output, the power must be extremely clean with fast responding regulators, and isolated from everything else.

Steve N.
Empirical Audio