In article , Rob
wrote:
On 09/02/2010 09:29, Jim Lesurf wrote:
In a.com, Rob



Though what happens if you replay audio snatched from a DVD? If you
are met with silence, you may have to occasionally reset output to
48kHz, and remember to set it back afterwards - or just leave it at
48kHz and hope that the internal circuits do a decent job of 44.1/48
resampling.


Yes, (but) I think iTunes sorts all that sort of thing out.

The DACMagic LEDs will tell you if the rate being output matches the
source material or not.


And . . . it depends. iTunes tends to sample up/down to 44.1,
regardless. I say 'tend' - if I use another application, Plex, for music
replay it changes system settings to 48/16 as if by magic - just FYI as
an example of the carnival going on behind the scenes. I can't find any
Mac software that will output the file in the recorded format.

IIUC the above shows that the Mac hardware is quite capable of providing
both 44.1 and 48. If so, your main 'challenge' (as managers say) is to find
software that simply passes out the data at the correct rates in every
case. Afraid I can't say anything about that with the Mac as I know little
about Mac software.

If I get a chance I'll ask a colleague who is a Mac user to see if he
knows. However my impression is that many computer users have zero
awareness of this issue and blindly assume that if they can hear sound it
must be "working OK". They then blame any nasty noises on the source
material.


However you could try asking Cambridge Audio.


There's a fair bit on t'internet, and it seems to make a pretty good job
of things using the correct settings, but apparently the USB interface
isn't up to much - sounded fine to me, have to say.

http://www.stereophile.com/digitalpr...r/index2.html#

Not yet looked at the above link. However I do get Stereophile on
subscription and remember reading the DACmagic review (and a later addition
to it IIRC). My impression is that operation with the USB will depend on
how evenly the computer sends the data. If so the real problem is initially
down to that.

FWIW When I started using my DACMagic i fed it from the computer via USB
and then ran an optical output from the DACMagic to my Meridian 563 DAC for
the actual conversion. In effect just using the DACMagic as a USB-SPDIF
convertor, and then having the Meridian reclocking the data to suppress any
jitter.

However I also experimented with using the DACMagic without the Meridian
and eventually decided that also sounded fine. Decided it sounded
indistinguishable to me. So I now just use the DACMagic and am moving the
Meridian on to other duties. Another advantage of this is that the DACMagic
can playback digital recordings at rates above 48k from my new HD P2.

Slainte,

Jim

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