My reference system includes a PS Audio DirectStream DAC, which will directly drive one amplifier but not two, and I needed to drive both my David Berning ZH-230 power amp and my JL Audio fathom f110 subwoofer. So I had to interpose my Audio Research SP20 preamp between the DAC and the amplifiers to adequately source them. I moved the Paul Pang USB cable to the PS Audio DAC and connected the preamp to my speakers and subwoofer, using the same cables I had with the Comet to assure the only difference in the comparison was the DAC, the preamp, and the interconnect between them. The PS Audio DAC had the latest upgrade, the Pikes Peak OS. The cost of this equipment used for comparison was $5995 for the DAC, $9000 for the preamp, and $1400 for the Clarity Cables Organic interconnect cable, for a grand total of $16,395.
On Concerto Symphonique No. 4, the PS Audio DAC produced very detailed sound, with even more harmonic accuracy than the Comet. The overall transient envelope of the piano was quite realistic, with initial transient, sustain, and decay all sounding very lifelike. In other words, it sounded a lot like a piano, but played in a somewhat percussive style. As with the Comet, dynamics were explosive. The PS Audio DAC sounded exceptionally good to me, but the Comet came doggone close to matching its performance on this challenging piece.
On “Melody Road,” the PS Audio DAC had slightly deeper, more forceful bass, and exhibited even more detail in the instrumental accompaniment. Diamond’s voice exhibited superb nuance.
On “Miserere,” the tenor’s voice was even smoother and more detailed, his slight vibrato becoming more obvious. The distant solo group was reproduced with amazing detail, more realistically than I’ve heretofore heard it. I could hear the individual singers better than ever. The impression of the distant location of the solo group was just ideal, the epitome of how detail and reverberation should be rendered, with none of the smeared echo I once had mistaken for portrayal of depth. The PS Audio’s performance of “Miserere” was a benchmark for the piece.
“Spanish Harlem” was pretty close between the two DACs, but I thought the PS Audio DAC conveyed the resonance of Pidgeon’s voice slightly more realistically, and I could hear more texture in her voice.
Overall, I was surprised how close the Comet came to the performance of the PS Audio DAC/Audio Research preamp. The latter was a bit richer sounding, with more detail, and amazingly good bass response, but considering the reference gear was over 6½ times as expensive as the Comet, the Exogal was clearly a way better value. The Law of Diminishing Returns was in play here.
The Exogal Comet looks great and sounds even greater. Easy to set up and use, it has enough flexibility to serve as the front end of most systems, although the extremely low impedance of its analog input severely limits the analog sources it can handle. The idea of using a smartphone app as volume control is clever, and works very well. If headphone listening is a high priority, I’d look elsewhere; the Comet’s headphone amplifier is limited in power. As a DAC and front end for digital sources, the Comet is a spectacular success and, especially at its moderate price, I strongly recommend you audition it in your system. It represents Exogal’s very auspicious entry into the marketplace, and I look forward to hearing the company’s future products.
SPECS & PRICING
Frequency deviation: 0.1 dB at 20kHz
THD: 0.007% (at -9 dB full scale and 400Hz)
Output voltage (on both the RCA and XLR outputs): 2.6V
Input impedance: 1k ohm
Output impedance: 9 ohms on the RCA jacks (unbalanced), 18 ohms on the XLR jacks (balanced)
Prices: $2500 ($3000 for Comet Plus with upgraded power supply)