For optimum sound quality you must feed the right bits (any manipulation will alter the sound) at the right time. Any variation in timing will have a negative impact on sound quality (jitter).
There are many claims that electrical activity going on inside a computer can disturb the clock of the DAC (or the SPDIF out).
As a consequence, minimizing electrical activity will have a positive impact on sound quality by reducing sample rate jitter.
An option is to read the entire song in memory first before playback starts.
This will eliminate the head movements of the disk during playback.
The purist will of course require a HD spin-down too….
Is this the usual audiophile nonsense?
Most of these claims are not backed by any measurement or ABX testing making it impossible to verify them.
Recently I found an interesting piece of information
Obvious there is a difference in jitter between the player in stopped mode and when playing. A spinning optical drive has its impact.
If we look at the values even when spinning, they are very low. So low I doubt this is an audible difference.
But it demonstrates the principle.
How do we translate this to the impact of head movements of a HD?
I can’t tell you.
My advice in situations like this is:
- take some very good recordings
- play them with/without memory playback
- if you don’t hear a difference then don’t bother.