ExaSound Audio Design e20 Digital-to-Analog Converter


Equipment report
Digital-to-analog converters
ExaSound Audio Design e20
ExaSound Audio Design e20 Digital-to-Analog Converter

S/PDIF Connection

While USB connections are needed to play DSD files, perhaps you just want a moderately priced DAC to play back your server’s S/PDIF output. I thought the e20’s S/PDIF input sounded just a bit less extended in the high frequencies on the percussion instruments in “The Panther.” And the bass on “Folia Rodrigo Martinez” had very slightly less impact, although the e20 was scarcely bass-shy. Does this mean the USB input was “better” than the S/PDIF input? Well, no; remember, different sources were used and different cables connected those sources to the e20, so it’s impossible to pinpoint which component may have caused the differences, which were very slight.

DSD Recordings

So finally to the question that probably interests you most: How did the e20 sound with DSD native files? To evaluate the e20’s performance with DSD files, I selected Channel Classics’ album Super Artists on Super Audio Sampler Vol.5 and downloaded both the 192/24 FLAC version (2406.9MB) and the original DSD (DFF format, 2956.4MB) version. I listened first to several FLAC files, beginning with Dejan Lazic playing the “Allegro” from Scarlatti’s Sonata in C major. I remember thinking how clean and detailed this recording of a piano sounded. Then, hoping I would be able to detect the difference, I cued up the DSD version of the same recording. Holy flaming cow! The DSD version of the recording made the FLAC version sound flat and mechanical. With DSD, it sounded like a different piano! The DSD version had the relaxed sound I associate with analog playback. In comparison, the FLAC piano sounded bleached and harmonically threadbare; and for some reason, the DSD version of the piece also sounded distinctly more dynamic. Reach-out-and-touch-it textures further increased the impression that, with the DSD recording, I was listening to a real piano. With the FLAC file, the piano notes just splatted into existence, while the DSD file’s piano notes sounded spookily real, beginning with the hammer hitting a string, the note launching into space, and then decaying off into silence as the note ended.

Next, I listened to The Netherlands Bach Society performing the “Quoniam tu solus Sanctus” from Bach’s Mass in B Minor. The same phenomenon occurred: The DSD recording was more realistic, easier to understand, and more dynamic. When the section transitioned to the “Cum Sancto Spiritu,” the way the soundfield opened up and the effortless increase in dynamic power was just thrilling. I could cite other musical examples, but they would all lead to the same conclusion: The DSD version of the recordings sounded superior to the PCM version—and the difference was not subtle.

Thinking that my limited assortment of DSD files may have restricted my findings, I tried some sample DSD files from Norwegian recording company 2L. But here, the superiority of the DSD versions of recordings over PCM versions was even more pronounced. I sampled a recording of the “Allegro” from Mozart’s Violin Concerto in D Major, played by Marianne Thorsen and the TrondheimSolistene, led by Øyvind Gimse. The 192/24 FLAC version sounded quite rich and detailed, but the DSD version just turned up the reality meter several notches. I remember wondering briefly if the soloist was playing a different violin in the DSD version, one that sounded gorgeous. Of course, it was the same violin on both versions. Who said digital can’t reproduce sweet string tone? The spectacular 2L recordings aren’t yet commercially available in DSD format; I hope that changes soon.


I have always regarded my AKG K701 headphones as a benchmark for high-frequency linearity, but the e20’s headphone amplifier gave them a high-frequency rise that sounded a bit bright. With headphones having a bit more roll-off (the Sennheiser HD 650s and, even more so, the HiFiMAN HE- 400s) the e20’s HF response sounded much flatter. And the e20s produced deep, very well-defined bass, quite spectacular through the HE-400. The combination of the e20 and HE-400s became a favorite, sounding sweet and detailed, but not the least bit bright.


My Audio Research DAC8 cost twice as much ($4995) as the e20, and is housed in a full-sized chassis with a sturdy but not terribly thick faceplate. As with most Audio Research components, the DAC8 is available in either black or silver finishes. Like the e20, the DAC8 is totally solid-state, but nevertheless sounds sweet and beautiful and dead quiet. Since it was brought to market before the DSD playback standard was developed, it doesn’t play DSD files; however, it plays PCM files up to 192/24 through all inputs except TosLink. Both ASIO and Windows Audio Session Application Programming Interface (WASAPI) drivers are available for the asynchronous USB input. I used the USB input with ASIO drivers.

Some quick sonic impressions: on “Folia Rodrigo Martinez,” bass extended just a tad deeper, and the instruments had a slightly richer harmonic presentation. Jennifer Warnes’ “The Panther” had excellent high-frequency extension, but the e20’s extended just slightly higher. On “Allegri Miserere,” the front choral group was just as well defined through the ARC, and I could hear more room reverberation from the distant solo group, which helped placed them farther back in the recording venue.

When I played the Scarlatti “Allegro” through the DAC8, the FLAC version sounded a lot more like the DSD version did through the e20. The piano’s notes sounded more fully developed, with a hammer strike, launch of the notes, and decay that sounded much more like a real piano. And dynamics were substantially stronger, much closer to the DSD recording through the e20. Unfortunately, the Audio Research won’t play DSD files.

Is it fair to compare the e20 to a DAC that costs twice as much? Maybe not, but it shows that as good as the e20 is, it’s possible for PCM files to sound even better; all it takes is lots more money.