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PowerBook G4 + Apple Express + iTunes +? to analog

My goal: Optimize my wireless Mac system to rival the quality of my Arcam CD192 CD player (running into an analog Arcam amp).

This isn't (yet) a question about brand recommendations (e.g., external DACs). At this point I simply need some help understanding how the system should be configured and what types of items I have to buy. I've already decided not to go with SlimServer or Sonos because I prefer to use my existing Mac computers + iTunes + Airport system as my source.

Current setup:

Office/server room:
1. Power Mac G5 dual 2.5
2. Lacie 500GB external drive (holds the Apple Lossless files)
3. iTunes running on the G5 ("iTunes Music Sharing" enabled)
4. Airport Express (802.11g) used as base station/Internet router

Listening room:
1. PowerBook G4 (next to listening chair, with iTunes channeling the shared playlist from the G5)
2. Mac out: analog 3.5mm headphone jack + RCA adapter
3. Amp in: analog RCA jacks on Arcam FMJ A32 + Dynaudio Audience 72 speakers

The audio quality with this set up actually is quite good on first blush. A/B comparisons with the Arcam CD192 are difficult, partly because the Mac source is about 5% lower in volume. I suspect that the Mac source is slightly less "authoritative" or "robust" than the CD player, but because I have to increase the volume of the Mac source to match the volume of the CD player, I can't be entirely objective. I also suspect that the Mac source might be somewhat fatiguing, but this could be due to the higher than normal volumes I used for A/B testing. So, while I'm not entirely convinced I actually need more components, I'll accept the conventional wisdom that an external DAC would overcome any deficiencies, fatiguing or jitter in the Mac source.

My questions:

If I buy an external DAC,

1. Must I buy an additional Apple Express for the listening room, or can I simply hook up the DAC to the PowerBook? (I would need a 24 foot cable to get from the PowerBook to the DAC/Arcam amp. An Airport Express could be located about 3 feet from the DAC/Arcam.)

2. Which type of DAC input -- USB, Firewire, or optical -- is recommended for this setup? Does the answer depend on distance from the digital source (question #1) or on the particular qualities of each connection? Or both?

3. Would I hear an improvement with only the DAC (versus analog headphone jack), or is an anti-jitter box recommended as well?

4. Must I change the way I use iTunes? For example, do I have to make the PowerBook G4 the "iTunes master," so that it directly accesses the library on the Lacie HD over the wireless network? Or is my current "shared playlist" method (using my G5 as the master) OK?

I realize that questions #2 and #3 are probably the most contentious and have already been asked on this forum, so I apologize for the repetition, but haven't seen a concise discussion of the issue of distance. Perhaps I missed it. Feel free to point me to other discussions as needed. Thank you!
syncrasy
sammie
220 posts
 
I'm rather new at this, and I can't comment on your "share" stuff, but I think I can share a few things I've learned about how to optimize for sound quality....

1. sound quality will be best if you go USB or Firewire from the powerbook direct to a DAC. Also, if you go USB or Firewire, the cable should be pretty short -- 1M or so.

2. Airport Express is certainly an option, but the DAC in the AE is not so good. And, if you go AE to a DAC, there's a lot of jitter created by the AE, which will again negatively affect sound quality.

I've tried both.....Macbook to USB DAC and using a AE. Macbook direct to DAC sounds much better.

3. You can use a Iphone or Itouch to control the powerbook remotely. I haven't tried this, but I've heard it works very well.
kjweisner's avatar
kjweisner
293 posts
 
I'll offer my own experience as a point of view although I do NOT have a Mac serving the music (PC). I have beeen streaming Apple Lossless wirelessly to three (3) AEs (one at each stereo), which in turn are feeding the DACs via Optical digital.

My collection is entirely from CDs I've burned to the hard drive, a number of which are HDCD. The relevance is that when these tracks come up the DAC's HDCD indicator is illuminated. IMHO, this suggest the data is fairly pristine and fully reconstructed just as it would have been from my CD transport. In practical terms, the AEs do a great job (to me) with the digits.

Where I've had issues is with interference (microwave oven) and dropped connections. I never could pinpoint or fault the AEs, the router, the wireless access point, etc. My office is in my listening room where I stream about 6-10 hours a day--having this working reliably is very important to me!

This weekend I pulled network cabling to all of the AEs so they're now hardwired to my network switch. Now, there's no interference, dropouts, etc. And I can turn on any/all of the systems for whole house sound that's perfectly in synch!

What Sammie said about using the iPhone or iTouch is true--I have an iPhone with the free "Remote" application installed and it's fantastic! Controls iTunes (play, pause, skip, find), displays the album art, playlists, etc. Very cool but only works w/iTunes which I don't consider a hardship at all!
syncrasy OP
14 posts
 
Thanks Sammie and KJ for your responses. I'm still assessing my situation and reading more on the topic.

KJ, why do you have both Airport Expresses *and* DACs? Are you doing this to bypass the AE's built-in DAC? Perhaps this explains why you haven't observed the AE jitter that everyone else seems to complain about. Can you clarify?
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