ЦАПы — Line Magnetic LM-32DAC

The LM-32DAC is a D/A converter made by Line Magnetic, a manufacturer in Foshan, China, best known for its reproductions of Western Electric designs. Launched in July 2021 at EUR 2,499, it offers a choice between a valve output stage and a solid-state output stage, selected from the front panel.

Key specs that matter

The DAC is built around the ES9028PRO Sabre with HyperStream architecture, and USB is handled by an XMOS USB 2.0 receiver. Supported sample rates are 44.1, 48, 88.2, 96, 176.4, 192, 352.8 and 384 kHz, plus DSD64, DSD128 and DSD256. There are five digital inputs, AES/EBU, BNC, coaxial, optical and USB, and the coaxial input has an impedance of 75 ohm. Outputs are one RCA pair and one XLR pair. The valve stage uses two 12AU7 double triodes and delivers 3 V with an output impedance of 2 kOhm, THD of 0.5% and 92 dB S/N. The solid-state stage delivers 2.5 V at 600 ohm, with THD of 0.02% and 98 dB S/N. Dynamic range is 120 dB A-weighted, and frequency response is 15 Hz to 50 kHz ±1 dB. The chassis is 430 mm wide, 325 mm deep and 105 mm high, with a weight of 6.7 kg.

Engineering and use context

The digital and analogue sections each have an independent power supply. The digital circuits run from an R-core transformer with transistor rectification, while the analogue side uses a toroidal transformer with a 6Z4 valve rectifier. Separating the two stops noise from the digital processing from reaching the output stages. The switchable output stages give two measurably different results from the same converter chip. The 12AU7 stage has a higher output but also a higher output impedance and higher distortion, whereas the transistor stage offers lower distortion, lower noise and a lower output impedance. Both stages feed the same RCA and XLR sockets, so the choice is made with a button rather than by changing cables. The broad input set covers computers over USB, CD transports and streamers over coaxial, BNC or AES/EBU, and televisions or game consoles over optical.

Pairing

The higher output impedance of the valve stage suits preamplifiers and integrated amplifiers with input impedances of 20 kOhm or more. With low-impedance inputs, the solid-state stage is the safer choice. A CD transport or network streamer with a digital output completes the source side.

Alternatives

The Line Magnetic LM-502CA is an earlier valve DAC with switchable 12AU7 and solid-state outputs and sample rates up to 192 kHz.