At this point, I rarely listen to music from traditional physical media (e.g. CDs). In the living room, I have the optical output of my Mac mini hooked up to my hi-fi, and an old Airport Express also hooked up via optical to the system. I used to use my laptop to play either my lossy or lossless iTunes library, streamed to the AX; or, alternatively use the remote controlled Front Row interface of the mini, displayed on my TV, to play music directly on that machine (as well as video...).
However, with the new iTunes remote, I just pick my a library, dial up my music on the iPhone, and have it stream to the AX. Easy and efficient.
By contrast, in the bedroom I have a Logitech SlimDevices Squeezebox 3. As I mentioned, it's a nice little unit. I bought it, for more money than I really wanted to pay, because it would pull music from my other computers, and give me an interface (via the built-in display and traditional remote control) to choose the music and control playback over my bedroom stereo, without having to walk to the living room or have a computer around. As a bonus it makes a nice clock and also displays the weather.
With the new Remote app, though, all of the music functionality could be had through my iPhone and an AX. As mentioned, I could obtain a late model AX for $60, and it looks like the Squeezebox 3 would pull $200 or so on eBay, leaving me with a net profit. As an added bonus I can have the same music playing over both the living room and bedroom hi-fis, see album art on the iPhone, etc. Plus, when I eventually end up somewhere else, more AX units make it cheap and easy to wire up more rooms for sound.
Besides losing a clock and weather display, the potential downside is audio quality. As I mentioned, the Squeezebox likely has a better DAC than the AX. I'd consider accepting that because my bedroom stereo is already a compromise from an audio perspective (assembled, as it was, for $400), and because an inexpensive, stand-alone DAC would probably make up the difference at some unspecified point in the future.
But, ostensibly being a man of science, this question of quality demands further investigation. Was there a measurable difference between the two units? An audible one?
Conveniently, the answer to the first question is readily available. Stereophile has reviewed both the Airport Express and the Squeezebox, and, even better, their reviews frequently include a thorough set of measurements.
Out of
Stereophile's measurements of the Squeezebox, the first relevant measurement is in Figure 1, the frequency response. There's a pretty striking rolloff of extreme high and low frequencies, particularly the low ones. The high ones are less important since I'll just become progressively more deaf to them as I age anyway.
Figure 2 is interesting too, showing the difference in volume of a low-level (-90 dB) signal and the noise level of the device (relatively steady at -110, but rising at the higher frequencies.
Perhaps most important is the decoding of a -90 dB 1 kHz sine wave (Figure 5). It's not quite as clean as
a state of the art component (cf. Figure 4), but it's got three relatively well defined voltage levels, which, as I understand it, is the truly important thing to look for.
Compare to the
Airport Express measurements. Frequency response (Figure 1) is quite flat, definitely better than the Squeezebox. Signal to noise (Figure 2) is better at low frequencies, but slightly worse at high frequencies.
Most interestingly, though, look at Figure 5, the sine wave. Visually, it's downright ugly. and not particularly consistent between cycles, either. So based on the graphs, you'd expect, maybe, that the AX would have more energy in the bass and high treble, but that the Squeezebox would be clearer, overall.
I'm not sure I noticed the former, although that could be a function of a 30-year-old receiver and a (relatively) small 8" subwoofer. The latter, though, I think was apparent.
I hooked both devices up in the bedroom, and it was easy to flip between them with a switch on the receiver, if not particularly convenient, requiring me to move from my listening position. I listened to some National, some Joanna Newsom, and some Ben Folds, and didn't really notice much difference. Both seemed reasonably clear.
But turning to Modest Mouse's "Float On" and Okkervil River's "Black", two favorite test tracks of mine... well, first of all, it seemed that the rendering of the Squeezebox somehow "sucked me in" more. I felt a stronger desire to continue listening, and I enjoyed it more. And, focusing in on a cymbal hit at around 20 seconds in "Black", I think I could hear a definite difference between the devices.
But this was largely an academic excercise. I love the Squeezebox and think it's a wonderful gadget, but the interface lacks a bit compared to the elegance of the iPhone's touch screen, it's pricey for a future multi-room expansion, it requires separate software, and it always is pretty much a hack to get it to integrate properly with iTunes. The Airport Express sounds good enough, in the final analysis, that I think I'll buy one and sell the Squeezebox. And maybe there will be an upgrade down the line, a $200 or so external DAC (which still keeps the total price below the retail of the Squeezebox). That's the nice thing about components with digital outputs—the important thing is that they're convenient and flexible. You can always make them sound better with a better DAC.
Anyway, that got pretty technical, but I think it's fascinating comparing measurements to listening. Hell, I find the measurements in general fascinating. Plus, I still think it's amazing how Apple, with a couple of seemingly unrelated hardware releases, and one seemingly tossed-off software release representing the final peace of the puzzle, makes itself a viable competitor in the multi-room digital audio market at a fraction of the price of other solutions. Apple's not even trying to compete in this segment, and yet they have a very competitive product just by virtue of building a few cool pieces of gear.
Labels: Apple, hi-fi
