This review page is supported in part by the sponsors whose ad banners are displayed below

“The shielded box contains a filter to reduce the electro-magnetic pollution (unwanted high frequencies) which come from the computer (processor, RAM, buses, switching power supplies). All of it will interact with the DAC to produce what we sometimes call a digital sound. All signals are filtered, not only the 5V power supply. I have worked before with mobile phones where these problem are common when digital is mixed with radio and audio. For example when your GSM mobile phone is communicating close to a hifi system or FM radio receiver, it can produce a 400Hz square tone which you can clearly hear. This is an example of electro-magnetic interference. This happens also from the computer to the DAC but you can't hear it as clearly. It just makes the sound more digital and you think that the DAC isn’t very good."

Operational quirks. Positioned 4cm from the DAC end of the cable, measuring 5.5 x 6 x 3.5cm and weighing 188g grams—heavier than most dongle DACs—the filter box poses logistical issues when connecting to full-size D/A converters. The weight of the filter placed too much strain on the PS Audio DirectStream’s USB port to require additional support for the filter box. This in turn necessitated sufficient shelf space behind the DAC. A similar scenario played out with the Aqua La Scala MKII. The filter box had to rest on an unused input cable.

Listening proper started in the head zone with the reviewer’s stethoscope: a pair of Sennheiser HD800. Schiit’s Bifrost Uber and Asgard 2 provided the respective D/A conversion and amplification. Upfront was a MacBook Air running Qobuz Hi-Fi + Amarra SQ.

The LightHarmonic cable doubly underscored the HD800’s straight-talking incision in the uppermost frequencies to contrast the TotalDAC D1 as the smoother talker of the two. For those who can’t get enough of the German dynamic’s deep X-ray abilities, the LightSpeed’s extension of separation and forensic analysis will be tough to resist. Or ignore. Old Red ensures front-row seats for greater exposure to on-stage pops, clicks, fizzes and farts. The TotalDAC takes the listener back ten rows. It burnishes the HD800’s pin and needles delivery and lowers the musical centre of gravity by emphasizing tonal mass.

Moving over to the higher-dollar drain of an Antipodes DXe music server, PS Audio Direct Stream DAC, AURALiC Taurus headphone amplifier and Audeze LCD-X headphones, the delta between Californian and Frenchman narrows considerably. A preference here proved too close to call.