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mjl
2010-01-10, 15:38
Any opinions regarding the best power source for a USB drive connected to the SBT?

I am wondering if this would have any impact on the sound quality. I am thinking of jitter and noise effects on the sound. An independently powered USB drive would result in less strain on the power supply of the SBT as opposed to the SBT powering the USB drive. I am thinking this might be the bast way to go but maybe my thinking is too simplistic. Any reasons why the SBT powered USB drive would be better other than the fact you'd have one less wall-wart?

Any thoughts on this?

m1abrams
2010-01-11, 08:38
Any opinions regarding the best power source for a USB drive connected to the SBT?

I am wondering if this would have any impact on the sound quality. I am thinking of jitter and noise effects on the sound. An independently powered USB drive would result in less strain on the power supply of the SBT as opposed to the SBT powering the USB drive. I am thinking this might be the bast way to go but maybe my thinking is too simplistic. Any reasons why the SBT powered USB drive would be better other than the fact you'd have one less wall-wart?

Any thoughts on this?

Well many usb drives require their own PS since they require more power than is allowed in the current USB spec. Only the compact usb drives (usually 2.5" drives) can be bus powered and many of those require more power than some usb buses can handle. However I seriously doubt the PS to the harddrive would have any sonic influence unless that PS is so power designed that it generates enough EMI noise to influence nearby devices.

georgeh
2010-01-11, 13:47
Interestingly enough, this user found both audible and measurable differences in the sound when he connected headphones to a touch.

http://forums.slimdevices.com/showpost.php?p=502303&postcount=273

So, it would seem that electrical loads may indeed have an impact, although wether or not you can hear that impact is subject to all sorts of factors.

Just food for thought.

m1abrams
2010-01-12, 14:46
Interestingly enough, this user found both audible and measurable differences in the sound when he connected headphones to a touch.

http://forums.slimdevices.com/showpost.php?p=502303&postcount=273

So, it would seem that electrical loads may indeed have an impact, although wether or not you can hear that impact is subject to all sorts of factors.

Just food for thought.

First off that thread that post is in is well not a good reference thread. Second the poster is talking about the PS to the harddrive not the Touch itself.

georgeh
2010-01-12, 20:01
First off that thread that post is in is well not a good reference thread. Second the poster is talking about the PS to the harddrive not the Touch itself.

I realize this is a contreversial subject, and not everyone is of a like mind, and that's fine. However, the OP was wondering if an additional power drain on the Touch could result in a jitter increase, and I was just pointing out that at least one person believes it's true. Yes, the OP was asking specifically about powering a drive through the USB, which is electrically different than powering a pair of headphones through the jack, so you can't draw a definative conlcusion about powering a drive through the USB. But I do think it is worthwhile to point out the findings of others in this general area.

I'm neurotic enough to believe the findings of John may have merit, and I'll be shopping for a drive with an independent power source, just to be sure. But I understand most people will think I'm a bit of a nut-job.:)

mjl
2010-01-13, 16:06
OP speaking ... thanks to all who replied and put in their 2 cents. I tend to agree with the last poster that the less extra stuff you ask the new SBT to do, like powering an external USB hard drive the less likely it is to introduce noise and jitter that can impact sound quality. Of course we have no way to prove this now but over the past few years I`ve heard what were identical lossless files being played through various setups; most of these with standalone DACS; Sonos, Apple Mini, Dell Computer with fancy sound card, SqueezeBox, etc. They all had their own unique sound signatures. Some of these sessions we just changed out the Dell with the Apple. Different sound. So the only conclusion I came up with is noise/jitter and what contributes to it is the electronic characteristic in each of these (ie. Apple vs. Dell) and the power management within these. Just a theory - but that`s what first got me to post this thread. As the last poster said it may be bit neurotic but I think I`ll go with the externally powered USB drive for my new SBT.

m1abrams
2010-01-13, 16:16
Some of these sessions we just changed out the Dell with the Apple. Different sound. So the only conclusion I came up with is noise/jitter and what contributes to it is the electronic characteristic in each of these (ie. Apple vs. Dell) and the power management within these. Just a theory - but that`s what first got me to post this thread. As the last poster said it may be bit neurotic but I think I`ll go with the externally powered USB drive for my new SBT.

Really that is the only conclusion you could come up with as to why your brain's heard something different? ;)

Also most large external disk drives will be self-powered, and for the Touch use I would probably recommend getting a self-powered drive too but not for sound quality but for reliability and cost (they tend to be cheaper per GB).

mjl
2010-01-14, 17:58
Hey, my brain is always hearing something different! Isn't that what this audiophile hobby is all about? :>)

Seven
2010-01-15, 10:50
So what self-powered drive do you guys recommend?