Интегральные усилители — SMSL AL400

The AL400 is a compact SMSL integrated amplifier from China that combines a DAC, a phono preamplifier, an HDMI eARC input, Bluetooth and a subwoofer output in one desktop chassis. It is built around a Texas Instruments TPA3255 Class D amplifier chip and a Cirrus Logic CS43131 converter, with an XMOS XU-316 handling USB and a Qualcomm QCC5125 chipset running Bluetooth 5.1, and it is aimed at both stereo and 2.1 systems including a television.

Key specs that matter

SMSL rates the AL400 at 2 x 85 W into 8 ohm at 0.003% THD+N and 2 x 165 W into 4 ohm. Signal to noise ratio is 101 dB and channel separation is 100 dB. The analogue line input has a sensitivity of 560 mV and an impedance of 22 kohm. The chassis measures 254 x 45 x 210 mm and weighs 1.7 kg, and the unit draws 40 W from a 100 to 240 V AC supply. The European price is around EUR 310, and black and silver versions exist.

Engineering and use context

Inputs cover one stereo RCA line, USB-C, coaxial, Toslink optical, a phono input accepting MM and MC cartridges, HDMI eARC and Bluetooth. Over USB the converter accepts PCM from 16-bit to 32-bit and from 44.1 kHz to 768 kHz, plus native DSD64 to DSD256, while coaxial and optical reach PCM at 24-bit and 192 kHz and DSD64 over DoP. MQA decoding works on USB, coaxial and optical, and MQA-CD is supported. The Bluetooth receiver handles LDAC, aptX Adaptive, aptX HD, AAC and SBC. A three-band parametric equaliser adjusts treble, midrange and bass, and each band has its own frequency, gain and Q control, the last one setting how wide a range the adjustment affects. For 2.1 use the subwoofer output has a low-pass filter selectable at 55, 85, 120 or 160 Hz, plus a phase switch between 0 and 180 degrees. A remote control is included.

Pairing

The AL400 can drive passive bookshelf or floorstanding speakers, and an active subwoofer connects to its own line output. A television connects via HDMI eARC, a turntable with either cartridge type goes straight into the phono input, while a computer feeds the USB-C port. Streaming from a phone or tablet goes over Bluetooth with the high resolution LDAC or aptX Adaptive codecs where the phone supports them, and the remote control lets the equaliser and inputs be switched from the listening seat.

Alternatives

The SMSL AS400 is a sister integrated model with DAC that relies on an Infineon MA5332MS chip and adds headphone outputs.