Power Amplifier Reviews

Measurements

Frequency response
81 Hz to 20 kHz ±7.9 dB

Bass limit
63 Hz at 94.3 dB

To measure the quasi-anechoic frequency response of the CEntrance speaker, I placed it atop a 2-meter stand and placed the microphone at a distance of 1 meter, enough to incorporate the contributions of all the drivers. I placed the microphone at the same height as the tweeter. I ran a ground plane measurement at 2 meters to get the combined response of the woofer and port, then spliced the bass measurement to the quasi-anechoic measurements. I used a Clio FW analyzer in MLS mode for the quasi-anechoic measurements and log chirp mode for the ground plane sweep, feeding the test signals into the line input of the CEntrance amplifier.

The graph shows the average of measurements taken at 0°, ±10°, ±20°, and ±30°, smoothed to 1/12th octave. As you can see, the tonal balance is admirably even from the bass all the way to 20 kHz, and that's especially unusual for an averaged measurement because the average takes into account the usual high-frequency roll-off at ±20° and ±30°.

But as you can also see, there's a big reinforcement/cancellation effect between 1 and 2 kHz, which suggests the crossover might have room for improvement. (I did try moving the microphone up and down to get a better measurement, but it didn't help.) The boosts at 1.3 and 2 kHz would probably be more audible than the scary-looking dip at 1.7 kHz. Off-axis performance is great, though; there's just a mild roll-off above about 4 kHz.

Bass output measurements, performed using CEA-2010 technique with the CEntrance amplifier powering the speaker, indicate decent bass performance for such a small speaker. I did get some measurable output at the next measured frequency of 50 Hz, but it was down -11.9 dB from the 63 Hz measurement, so it would be barely audible. - Brent Butterworth

Bottom Line

Anybody looking seriously at a small system like this these days is probably trying to simplify, without giving up anything in raw performance terms. Since for many these days a single source - be it a computer or a set-top-box or a tablet or a high-end-media streamer - acts as primary gateway to a wide variety of digital audio content, from Internet radio to streaming services to local libraries, there's little need to clear space on your desk for an AVR to handle routing. Thus a little integrated amp like the DACmini PX makes a whole lot of sense. Even more so if you're using the PX's aesthetic inspiration and sibling in footprint, the Mac Mini, as your music server. Maybe you have a treasured analog source? That extra analog input lets you rope in your vinyl (you'll need a phono preamp, of course) or reel-to-reel.

The cost is a little prohibitive for most, obviously. And that's really the rub here - if you're looking at this as a room-filling solution (in which capacity it could easily serve), the cost of the ADS might begin to give pause, since you could put together something larger and louder for less. CEntrance suggests a dorm room application; given the price, that dorm room might have to be at Bennington. But as the name - Audiophile Desktop System - implies, this is really meant for those looking for a personal critical listening setup, and given how well it performs, the tariff may not be too much to bear for the folks looking for really impressive performance in the near field, or perhaps interested in trying out the coaxial/coplanar concept.

And judged on those criteria, the ADS delivers. It really is an impressive-sounding little system, with sterling performance across the audio spectrum. And if you look at this as a personal listening system, it doesn't cost any more than, say, a pair of Audeze LCD-3 headphones, or an LCD-2 and a pretty nice headphone amp.

Bassheads might want a bit more bottom, but given that this is a 2.0 system with such a small footprint, it delivers plenty of kick. There's no dedicated sub out on the DACmini PX, though perhaps that - plus an appropriately tiny matching sub - might make a nice follow-up project for CEntrance.