ЦАПы — Audio Note DAC 4.1x

The DAC 4.1x is a valve output D/A converter produced by Audio Note (UK), sold as the DAC 4.1x Balanced and the DAC 4.1x Balanced Signature. It uses the 18-bit Analog Devices AD1865N converter and, like the rest of the company range, is designed to put sonic performance ahead of technical specification figures.

Key specs that matter

The unit accepts digital signals through a 75 Ohm RCA S/PDIF input or a 110 Ohm XLR AES/EBU input, at sample rates of 44.1, 48 and 96 kHz. Both the XLR and the RCA outputs have a 600 Ohm output impedance, and channel balance is within 0.2 dB. Reference output is 1.5 V RMS for the Balanced version and 3.2 V RMS for the Signature. The casing measures 145 mm high, 450 mm wide and 425 mm deep, and weight is 18 kg for the Balanced and 19 kg for the Signature.

Engineering and use context

The circuit contains no oversampling, and Audio Note equally avoids any jitter correction, noise shaping or clock regeneration, stating that music is a time continuum that is irreparably damaged once broken. The filter interface coils and transformers use cores of 80 percent nickel super mu-metal. The power supply uses valve rectification followed by double choke filtering. Audio Note capacitors and tantalum film resistors are fitted throughout the circuit. The two versions differ in their analogue output stage. The Balanced model uses an upgraded version of the output stage from the M6 Line preamplifier, with a 5814a and a 6463 double triode valve. The Balanced Signature instead uses a pair of 5687 double triode valves, which accounts for its higher output level and extra kilogram of weight.

Pairing

With XLR and RCA outputs available, the DAC 4.1x connects to balanced or single-ended line inputs on a preamplifier or integrated amplifier. The lower output of the Balanced version is a point to check against the gain of the partnering amplifier, whereas the Signature delivers a level closer to other Audio Note converters. A CD transport or streamer can feed it through either the coaxial or the AES/EBU input. The full width lines up with the larger Audio Note electronics in a rack.

Alternatives

Further up the catalogue, the Audio Note DAC 5 Special keeps the AD1865N converter and the same chassis size but adds a dual mono power supply and a 5687 valve output stage.