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Design: All three devices share the same aluminium housings differing only in their front and back panels. This significantly reduces manufacturing costs. These boxes are very small and lightweight. Dimensions are 105 x 46 x 104mm (WxHxD). And here's the problem. They cannot be placed such as to resist moving about with any stiffer cable like an Oyaide which will up-end ‘em. I think that it would be useful to devise some kind of mini rack for all three, holding them together for more weight made perhaps of wood like an old Marantz—or metal?—seated atop good anti-vibration feet. It should be functional and include a system for cable routing. And look good. All these M2Tech boxes are made in Italy by the way.


hiFace EVO. This is an asynchronous 24/192 digital-to-digital converter that converts USB to S/PDIF in five different forms – coax, I²S on Ethernet socketry, Toslink, ST and AES/EBU. Its proper full name is HiFace EVO 192kHz 24-bit Digital Audio Interface. In short we can say that it converts the digital signal that's output via USB to a digital signal that’s 'understandable' by classic D/A converters. The front panel sports four electrical outputs—I²S, AES/EBU, coax and BNC—while the optical outputs of TOSLINK and ST are at the back. Here we also find a USB 2.0 input. The company offers a suitable driver on their website. Next to the USB socket is a green LED to confirm synchronization between converter and computer.

There are two more inputs - BNC for an external clock also with LED; and a power socket for an external 7-11VDC power supply with another light diode. The entire circuit is mounted to a single PCB. In its center is a Xilinx Spartan XC3S50A DSP which houses the software-driven converter. The same IC is used in the company’s Young D/A converter. All electrical outputs and the clock input feature isolation transformers for galvanic isolation from the PC. Optical outputs are isolated by definition. Adjacent to the DSP chip we find two nice clocks for the 44.1kHz and 48kHz sample-rate families. The power supple socket is equipped with an active low-pass filter to improve the AC quality.


EVO Supply. This is a battery power supply for M2Tech’s entire EVO family of products but not just for them. It is based on three Li-Ion 2200mAh batteries. The power supply provides current to 1A peak and 500mA constant at 9V (low-noise power supply) or 9.5-11V (rechargeable). Its front panel is bare. On the back we have a socket for an external 15VDC power supply and two voltage outputs. Those are very nice. Next to them we find two switches: 'battery/charge' with an LED and 'on/off'. The first selects the operating mode. We can either work only on batteries with the mains disconnected or with an automatic power supply. In the latter case the batteries are automatically recharged if needed. After charging the charger disconnects. Together with the power supply we get one charging cable. Its plug on the power supply side (5.5x2.1mm) is excellent but the cable itself is rubbish. Inside the case we have three battery cells and the accompanying charger circuit. The voltage outputs for the external devices feature additional electronics but I couldn’t determine what those were.


EVO Clock. This is a high-precision external master clock based on low phase noise and very accurate temperature-compensated crystal oscillators. As we read in the manual, clock stability could be improved even further using OCXO oven-compensated crystal oscillators with their own heater that keeps the oscillator’s temperature constant but those are very costly. The EVO Clock is used primarily for controlling the hiFace EVO converter but not exclusively so - it's very versatile. With the M2Tech converter we use two oscillator frequencies: 22.5792MHz for files with sampling rates of 44.1, 88.2 and 176.4 kHz; and 24.576MHz for 48, 96 and 192kHz. A small switch chooses between them. I'd rather have this automated but no problem. The EVO clock provides a 3.3Vpp at 75Ω output.

However one can use this clock also for many other devices. Hence the large knob in the center of the front panel. Here we choose the sampling frequency between 44.1 up to 384kHz with a ‘super clock’ option of x 128 and x 256. The output signal may have the value of 3.3Vpp at 75Ω or Lo-Z for high-impedance inputs. At the back of the unit we have two BNC connectors - one for the MCLCK output (EVO devices) and the other for WCLCK (other devices). Unfortunately I do not know whether this M2Tech clock can send two signals at the same time, allowing a common clock for D/D converter and DAC. There also is a socket for a 9VDC external power supply with an LED.

This circuit too is assembled on a single PCB. In its center are two large quality clocks for the 44.1 and 48kHz sampling rate families. Next to them we have a large Xilinx DSP with software-driven PLL loops to control the desired clock frequency. BNC outputs feature matching transformers for galvanic system isolation. The power supply socket is equipped with an active low-pass filter circuit to minimize noise.
opinia @ highfidelity.pl
M2Tech website