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View Full Version : Follow up to CD transport vs Squeezebox sound quality



Jason
2004-06-01, 18:23
I would like to know this also.

-----Original Message-----
From: discuss-bounces (AT) lists (DOT) slimdevices.com
[mailto:discuss-bounces (AT) lists (DOT) slimdevices.com] On Behalf Of dean blackketter
Sent: Tuesday, June 01, 2004 5:08 PM
To: Slim Devices Discussion
Subject: [slim] Follow up to CD transport vs Squeezebox sound quality

Eric,

Thanks for the report. I'm curious, did you do the A/B testing blind or did
you know which input you were listening to during the test?

-dean

On Jun 1, 2004, at 3:13 PM, Eric Brandon wrote:

> In an earlier post I reported hearing no difference between the
> Squeezebox and a $3500 Wadia 860x CD transport. That test fed the
> signals to a $4500 dCS purcell upconverter which reclocked and
> upconverted the digital signals before sending them to the DAC. I was
> asked to try connecting the Squeezebox and the CD transport directly
> to the DAC and report again. Here is that report.
>
> I ripped Patricia Barber's "Companion" as WAV files using iTunes.
> This is a
> great test disc because it is extremely well recorded, it is a live
> "unprocessed" performance using acoustic instruments, and there is a
> lot of space between the notes allowing the listener to really focus
> on the attack/timbre/decay of individual notes by individual
> instruments. I also created Apple Lossless Codec (ALC) copies of the
> WAV files to try that out too.
>
> I was able to A/B compare the CD transport to the Squeezebox by
> switching the DAC's input source on the remote control while both
> played. Volume appeared to be exactly matched.
>
> Results
> 1) The Squeezebox did not sound quite as good as the Wadia CD
> transport. On the Wadia the bass sounded tighter and better focused.
> Patricia Barber's voice was more realistic on the CD, sounding a
> little "chesty" on the Squeezebox. Finally, the with the Wadia the
> instruments were better defined in space, both individually and in
> relation to each other.
>
> The differences were not enormous. I think it is fair to say the the
> Squeezebox sounded about the same as hooking up a typical Sony DVD
> player or SACD player to the DAC and then playing the CD on that. The
> Wadia is just an extraordinarily good, optimized-for-CD, transport.
>
> 2) I could detect no difference between WAV files and ALC files played
> on the Squeezebox. There was no way to do a realtime A/B test of this
> however.
>
> Conclusions
> 1) The Squeezebox does benefit from having its digital output
> reclocked and upconverted by an outboard digital signal processor.
> With this additional step, it sounds as good as the best CD transport
> I know.
>
> 2) There are many other variables that could be tested that might
> explain these results or narrow the gap.
>
> a) The Wadia CD transport stands on very sharp little spikes that help
> isolate it from vibrations of the shelf caused by the loudspeakers.
> Perhaps putting some vibration isolation mats or spikes under the
> Squeezebox would narrow the gap I heard here. (p.s. if you think this
> is crazy talk think about the fact that the vibrating device vibrates
> the cables that are attached to it.)
>
> b) The Wadia has a heavy, expensive, power supply that reduces the
> effect of grunge on the AC line modulating the timing the and
> crispness of the
> square-
> wave that carries the clock timing in the digital signal. Perhaps
> plugging the Squeezebox into a power regeneration device such as a PS
> Audio powerplant would help.
>
> c) There are a lot of other variables we could test -- ripping with
> itunes vs EAC, Squeezebox optical vs. coax output, etc. Who knows?
> That what makes this hobby fun.
>
> - Eric
>
>
>