SFD-2

About the SFD-2

The Sonic Frontiers SFD-2 is a high-end digital-to-analog converter (D/A processor) with a fully balanced vacuum-tube output stage using two Sovtek 6922 (6DJ8) dual triodes. It uses differential 20-bit UltraAnalog DACs with 8x oversampling digital filtering, and provides three digital inputs: coaxial S/PDIF on RCA, AES/EBU on XLR, and AT&T ST-type optical, plus one S/PDIF digital output on RCA. Analog outputs consist of one pair of single-ended RCA and one pair of balanced XLR connectors. The specified performance includes a frequency response of 5Hz to 20kHz ±0.5dB, signal-to-noise ratio greater than 110dB (A-weighted), total harmonic distortion of 0.05%, and channel separation better than 105dB at 1kHz. Output level is 3.5V single-ended and 7V balanced. The chassis measures 19" W x 4" H x 13" D (48cm x 10cm x 33cm) and weighs approximately 26.5 lbs (12kg). Introduced in the early 1990s and now discontinued, the SFD-2 is widely regarded as a classic tube-based DAC noted for its refined, musical presentation and strong build quality.