Acuhorn R2R XT

R2R + DHT = ? – If you're Wojciech Underschütz of Acuhorn from Poland's Gdansk, its the recipe for a Soekris-based R2R DAC with global-voltage Vicor switching power supply and 2.5/4/5V direct-heated triodes like the 45, PX4, 2A3 or 300B. For €6'900, it's a fully balanced affair, for €5'700 it's single-ended. For €4'000, big DHT turn Sylvania sub-miniature 5987 triodes. In either case, there's USB, coax and Toslink, 28-bit resistor precision and data compatibility of 384kHz PCM and DSD256.