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silverlight
2009-04-21, 06:03
Hi - quick question, as I couldn't find a clear answer on this in the archives --- if I set the Mac default output in the Audio MIDI Setup program to 24/96 2 Channel, will all files fed to the Transporter be sent in 24/96 (upsampled from 16/44.1 where necessary)? Reason being that I'm working with an external DAC and de-jitter solution and it's an additional cost to have an upgraded 16/44.1 clock added and if everything is coming out in 24/96 I can ignore it. My source files are a combination of ripped CD's at 16/44.1 (Apple Lossless or AIFF) and downloaded WAVE at 24/96.
Thanks for any insights!

radish
2009-04-21, 07:40
Audio settings on the server machine make no difference to SB players such as the TP. You can probably setup SC to upsample everything to 24/96 with SOX if you need it, but it will take a bit of tweaking.

abqpete
2009-04-21, 07:49
Silverlight,

What is your connection scenario? Are you feeding the Transporter directly from the Mac's digital output? If yes, then what you describe is true as the Audio Midi settings will do sample rate conversion (as needed) to whatever you select.

However, if your Mac is running Squeeze Center and sending the music via the network, then your Audio Midi settings have no impact.

Regards, Peter

silverlight
2009-04-21, 09:24
Peter- I will be using a network connection using wireless N (have an Airport Extreme at my home theater to connect BluRay, TivoHD, AppleTV, TP with ethernet cabling). Transport will be connected to an Empirical Audio Pace Car 2 (word clock + Toslink connection) which then in turn will connect to my Meridian 568.2 serving as the DAC to Krell amp, etc.
(note: I say I will be using as I just ordered the TP and should be arriving next couple days)

On the fly upsampling by SqueezeCenter sounds like a possibility then. (although I'm sure the quality would be better if I did it on my own with r8brain/Win or Adobe's Audition, but that would be time consuming).

Related question - if I have a 16/44 file (Apple Lossless or AIFF) then without a modification, it will pass this through, likewise with 24/96 AIFF both as is? If I download a 24/192 file, the SqueezeCenter will convert to 24/96?

Thanks!

radish
2009-04-21, 09:56
Peter- I will be using a network connection using wireless N (have an Airport Extreme at my home theater to connect BluRay, TivoHD, AppleTV, TP with ethernet cabling). Transport will be connected to an Empirical Audio Pace Car 2 (word clock + Toslink connection) which then in turn will connect to my Meridian 568.2 serving as the DAC to Krell amp, etc.
(note: I say I will be using as I just ordered the TP and should be arriving next couple days)

I might suggest listening to the TP on it's own - it's pretty good...also without the pacecar. Check the audiophile forum for more opinion on that, I remember it being discussed.


Related question - if I have a 16/44 file (Apple Lossless or AIFF) then without a modification, it will pass this through, likewise with 24/96 AIFF both as is? If I download a 24/192 file, the SqueezeCenter will convert to 24/96?

Up to 24/96 will be transcoded to FLAC at the native rate. 24/192 will be transcoded and downsampled to 24/96 FLAC.

silverlight
2009-04-21, 11:22
I might suggest listening to the TP on it's own - it's pretty good...also without the pacecar. Check the audiophile forum for more opinion on that, I remember it being discussed.


Up to 24/96 will be transcoded to FLAC at the native rate. 24/192 will be transcoded and downsampled to 24/96 FLAC.


Thanks Radish, that's very helpful. Out of curiosity, is the transcoding to FLAC lossless at the bit level? (i.e., should I be concerned about not using FLAC files as source material, not that Apple/iTunes supports it yet anyway from what I've read...)

I did see the discussion on de-jitter boxes in the Audiophile section. I've read alot about this on the net, stereophile, and chatted with a few engineers/audiophiles and certainly an active discussion. Ultimately our ears will decide, and will definitely do some A/B comparisons as the DAC in the TP seems to be well reviewed and regarded. I'll also try using the Meridian with and without the Pace Car 2 to see what changes. Guess it will depend alot also on the synergy between the various components and cables (or lack thereof) and personal preferences.

Phil Leigh
2009-04-21, 11:23
Peter- I will be using a network connection using wireless N (have an Airport Extreme at my home theater to connect BluRay, TivoHD, AppleTV, TP with ethernet cabling). Transport will be connected to an Empirical Audio Pace Car 2 (word clock + Toslink connection) which then in turn will connect to my Meridian 568.2 serving as the DAC to Krell amp, etc.
(note: I say I will be using as I just ordered the TP and should be arriving next couple days)

On the fly upsampling by SqueezeCenter sounds like a possibility then. (although I'm sure the quality would be better if I did it on my own with r8brain/Win or Adobe's Audition, but that would be time consuming).

Related question - if I have a 16/44 file (Apple Lossless or AIFF) then without a modification, it will pass this through, likewise with 24/96 AIFF both as is? If I download a 24/192 file, the SqueezeCenter will convert to 24/96?

Thanks!

I think you will find that on-the-fly upsampling via SOX is as good as it ever needs to get. Bear in mind that ALL upsampling is simply adding things that are not really there...

radish
2009-04-21, 12:17
Out of curiosity, is the transcoding to FLAC lossless at the bit level?
Yes it is.

abqpete
2009-04-21, 19:13
In addition to what has already been said, do not forget that the Meridian 568.2 will upsample 44.1 to 88.2 via their own algorithms. I remember Bob Stuart telling me that they spent a lot of time testing various upsampling techniques and settled on what they thought was best.

Regards, Peter