I submitted a query to Panasonic about the optical digital input. They responded that it supports "LPCM, Dolby Digital and DTS". Would LPCM imply that it supports the digital audio out from this unit? Sorry for my naivety.

By the way, to those in the US, this can be found now online at Officemax http://www.officemax.com/technology/ipod-mp3-players-accessories/ipod-mp3-speakers/product-prod4380302. They have it listed for 94.99 with free shipping. Better yet, you can pad your order over $100 (I used some pens/pencils which were clearance) and one of the below coupon codes to get $25 off. Plus you can probably get cashback from ebates or fatwallet. So basically you are getting this for $70 plus the cost of your padding and tax. Needless to say I picked one up and hopefully it works with my system.
 
Below are the codes to try.
 
$25 off $100 expires 03/16/2013

KPD1386734KDGXFP
KPD1390XXVWYMB4TC
KPD12F0NXHDT2GK3C
KPD13855XXJ9WYJNC
KPD13857VYVBNR6BC
KPD13860JN306SHVC
 

Okay, I'm new to this stuff (even if I spent years as an obsessive analog audiophile).  So pardon me if this is a stupid question.
 
I'm trying to set up a music server for Apple Lossless files, to drive high-end speakers (Joseph Audio).  Initially I thought I'd use an old MacBook, plugged into a Schiit Modi DAC and then into the amp.  BUT...
 
How much in terms of sound quality would I lose if I were to put ALAC files on an iPod Classic, and use this PURE i-20 as a DAC?
 
Is the difference *solely* the difference in quality between the two DACs?  Or is there some other sonic benefit derived from using a MacBook rather than an iPod as a source?

Experienced reviewer Skylab reviewed the PURE i-20 as a transport, which promptly caused him to sell his Wadia iPod transport. The notion of using the i-20 (with lossless material) or similar devices in a high-end speaker system is perfectly fine.

The built-in DAC did not impress Skylab so much. But here's the thing - you could start with it and add a standalone DAC later.

As to MacBook versus iPod/i-20 - I have a bias that built-for-one-purpose devices such as the latter pairing should sound better. But it's just a bias. I have not directly compared these situations.

I run my Plinius powered speaker system from the PURE most of the time. Results are superb. However, the quite well-regarded 'Eastern Electric' DAC is used in place of the PURE's.

Thank you!  In terms of output, then, the iPod doesn't do anything weird to the digital stream:  it should arrive at the DAC bit-perfect, and indistinguishable from what emerges from the USB port of the MacBook?  (Not sure why, but I had some sense that files were down-sampled when loaded onto the iPod...)

I just tracked down what I'd read regarding this.  Turns out it was here on head-fi:
 
"I read a while back on Stereophile that the iPod played 48-24 files BUT (and it's a huge but here) truncating on the fly to 16 bits. This matches my experience with my iPods the take and play 48-24 ALAC files but truncating (not even dithering) them."
 
The discussion did not conclude in any way that really put me at ease.
 
 
The conversation is here:  http://www.head-fi.org/t/544673/ipod-classic-best-bitrate-and-sample-rate

Hmm. In my case most of my material is lossless but redbook sourced. Hence, I don't have a problem., i.e. in this scenario the iPod/PURE is bit-perfect.

Higher res material might be an issue for you. In terms of SQ I haven't noticed differences (from my Mac feeding my headphone rigs) between higher res and redbook material. But then I haven't been looking for them, put off by reports of tracks re-issued to show off high-res having been re-mastered at the same time!

I have an open mind on the subject, but the quality of performance in my systems doesn't have me worried at the moment.

As well, if you're new to head-fi be warned that for every well-supported view there is an equally well-supported counter-view, together with many strange pockets of thought this way and that!
I guess it gives us all the opportunity to find the clique most congenial to us

Well, you've introduced me to a new concept.  Well, a new term, anyway.  Anything ripped from a bog-standard CD using iTunes will be "Redbook", right?  And ordinary FLAC files converted to ALAC via XLD?  If I have bit and sample rate set to "same as original", I'm going to get Redbook? 
 
In which case, I'm golden:  that's all I'm looking to play.
 
I'm assuming ordinary FLAC files are 16/44.1 -- perhaps I shouldn't.  I do have the option of setting XLD to convert to this sample rate and bit depth:  is that wiser?
 
By the way -- if these questions are too elementary, feel free to point me to the right place to talk about this...

You'll see "Redbook" a lot. It refers to the original specification behind the CD (44.1, 16 bit) format. There's a thread somewhere round here that goes into the history.

Concerning your FLAC question, I have some Alice Sara Ott downloaded in FLAC. Forget the advertised specs, but once added to iTunes using Audirvana it appears as AIFF at 1411 kbps. That sure suggests its higher than redbook.
It has also migrated to my iPod perfectly happily. I can even play it.

That said, it's completely possible your link is right about the iPod truncating these tracks to red-book (a hardware or OS rather than an ALAC/FLAC limitation I suspect).

IF so, as you know the PURE can't help. I suggest you look around a bit more - there will be head-fiers far more knowledgeable than me on this question.

I wish I could point you to the right place!! Head-fi's pretty big. One tip - google is usually more effective locating relevant head-fi threads than head-fi's own search. Good luck!

Thanks.  I'm using Audirvana as well (although I convert to ALAC, rather than using it to play FLAC files).  Brilliant software.  I've noticed something odd, and it will be interesting to see how an iPod with i-20 deals with this scenario:
 
I've inherited some Ray Charles tracks that are tagged as 96 kHz in iTunes. When they're played through Audirvana, they're identified as 48 kHz.  Wonder what's going on here.  And whether I should just deal with potential problems in advance by having XLD simply convert everything to 44.1
 
 
UPDATE:  Just for the hell of it, I had XLD take the same FLAC file and convert it at 44.1 -- and I'm A/B'ing the two versions.  Can't hear any difference on this system (an iMac through a uDAC-1 into Grado SR1-125s).  Which isn't to say that I wouldn't hear it on a different system, or with different files.

I don't know either, but the thing about 96 is it's a clean multiple of 48. You'll notice sample rates are generally 1,2 or 4 x the two base rates of 44.1 and 48 Kbps, e.g. you'll see dacs increasingly rated on ability to handle both 192 and 176.4 kbps.

Maybe audirvana is identifying the base rate, idk. Would be wise to find out before converting everything to 44.1. There's a possibility conversion from e.g. 96 to 44.1 will generate artifacts (at any rate, see what Jason Stoddard of schiit has to say about up sampling, the opposite process...).

You've raised some good questions.

Good -- I'm glad I'm making sense.  Does OS-X's Audio Midi setup have something to do with this?  Oddly enough, the Midi panel won't *allow* me to choose 96 kHz.  The only options I have are 48000.0 and 441000.0 -- which makes it impossible to set things up according to Nuforce's instructions.  (They also specify 2ch- 24bit, and this doesn't come up as an option either.)
 
Is Midi perhaps dictating to Audirvana that 48 kHz is the maximum?

I think (not sure) Audirvana bypasses or dictates to Midi.

But you are best to take this out of this forum as we are straying away from the i-20 - and my area of knowledge.
You should be able to find a forum on head-fi that talks about setting up OS-X and Midi...

Quote:

grindingthud said:

I can control volume to my WA3 over the analog out via the iPod. The i20 remote controls the volume also. Not sure what effect it has over the toslink.

Click to expand...

The volume can be controlled over toslink as well. Yes its possible to hook up the active monitors directly from the i20. All you really need to tweak is the volume setting on each speaker to find a sweet spot that allows play with volume control from the i20.

For best audio quality have the i20 volume at Max, in theory I think this is bit perfect.  Adjust the volume with your amp.