MEASUREMENTS

I measured the DirectStream MK2 first using my Audio Precision SYS2722 system,¹ then with the magazine’s higher-performance APx500. The review sample was fitted with the v2.3.5 FPGA firmware, but after I experienced some anomalous measured results, I installed the v2.3.3 firmware package, which was available as a download on the DirectStream MK2’s information webpage. I then installed the v2.3.6 firmware when it was available and repeated the testing.

The DirectStream MK2’s optical input locked to sample rates up to 96kHz, the coaxial and AES3 inputs locked to datastreams with all sample rates up to 192kHz. Both Roon and Apple’s USB Prober app identified the USB-connected D/A processor as “PS Audio Extended Resolution USB” from “PS Audio,” with the serial number string “Version 3.02 11/30/2022.”