External hard drives and sound quality


I've just about filled up the internal hard drive on my Macbook with music files and am now looking at external hard drive options. Was wondering whether folks report any difference in sound quality when playing files from an external drive versus the internal?

I'm especially interested in hearing people's experiences using wireless hard drives. An Apple rep told me it would be no problem, as the hard drive wouldn't directly interface with the USB output, but I of course always like to be skeptical of anything an Apple rep says.
coverto
Hi
I have a P4 based system with Windows XP SP3 OS and use cics memory player ( CMP2 ) for highest quality music playback.

I use EAC to rip CDs to hard disk and have a 40G SATA connected internal drive and have just added a Western Elements 1 Tb external drive that is powered via AC and connected via USB.

I started ripping to new drive and played back a few albums and thought somethings a miss here, a bit harsher sounding, less real and involving....

so re-ripped a track to each drive for an exact test comparison...'Bennie and the Jets' as I was ripping Elton John's 'Goodbye Yellow Brick Road'.

In CMP2, track is loaded from hard disk to RAM and all playback is from 'RAM', even so the differences are clear, my internal Seagate drive sounds..more more information, more presense, and more emotionally involving, rythmic and listenable, engaging...

by comparison the external drive was as aforementioned previously above......so differences could be cable related, usb as opposed to sata this being compounded as remember music is first copied then resent from the hard drive back along the cable for another journey before playback, or power supply, or internal electronic makeup of the drives, and/or any combination of these factors...

so in my system, which also includes a NAD304 Amplifier, DAC
is SB Audigy 24bit internal sound card, Cardas interlink up to amplifier and some custom 3 way in-wall speakers, there are sound quality differences.

:) Stephen
I have another question concerning external hard drives and sound quality. What if I was using a USB DAC without external power? Will a hard drive on another USB port affect the voltage given to my DAC which in turn can degrade sound quality?
From my experience of external hard drives I have went for SSD drives because they produce far less jitter than the old platter type drives as they have no moving parts. Also I would use USB with a reclocker as that is also far superior to wireless but good luck in whatever you chose because you shall come up against many detractors as that is the way of the beast I'm afraid.