Hi-End S/PDIF Output Interface
hiFace Evo by M2Tech is the new statement in high quality computer audio interfaces. Hosted in a compact and stylish aluminium case, hiFace Evo is capable of flawlessly transfer audio data up to 192kHz, 24 bits to virtually every DAC or A/V receiver around, thanks to its comprehensive outputs set. hiFace Evo incorporates the same leading edge technology as the classic hiFace âˆ’ with some plus. Asynchronous operation up to 192kHz is used in conjunction with proprietary drivers which allow for Kernel Streaming, Direct Sound and WASAPI operation (the latter under Windows vista and 7). Windows and Mac drivers are already available. Very high precision, very low phase noise (jitter) crystal oscillators are used. To further improve their performance, they have a dedicated shunt voltage regulator which ensures a very low noise and spurious-free supply. hiFace Evo is powered by an external power supply (not included), to avoid the dirty USB bus supply from negatively affecting hiFace Evoâ€²s performance. Linear regulators are used all around, to allow all jitter-sensitive digital circuits to operate at their best. Also, a low-pass filter is provided at supply input to further reduce any bad influence from the supply. hiFace Evo can be powered by an external wall adapter (9V 1A will fit), or with a 9V alkaline battery, or with a 7.2V/10.8V Lythium battery. Several outputs are available at the same time: coax on RCA, coax on true 75 Ohms BNC, AES/EBU on male XLR, optical on Toslinkâ„¢ (Toslinkâ„¢ is guaranteed to operate up to 96kHz, though we got operation up to 176.4kHz on certain setups), optical on ST (for high-speed operation up to 192kHz and up to 1.6km or 1 mile), straight I2S for direct connection to DIY DACs on RJ-45 (NOT plug-in compatible with NorthStar products!). All outputs, except straight I2S, are galvanically isolated (coax and AES/EBU via a pulse transformer). AES/EBU output can be set to professional or consumer mode by an internal jumper. In addition, an input for an external clock is available, for those who have a extremely precise and stable clock generator to be used with hiFace Evo. hiFace evo automatically recognizes the presence of the clock on its input and switches on it whenever available. This input is also galvanically isolated via a pulse transformer. Three LEDs indicate power, external clock presence and incoming data from the PC. Connection to the PC is via a type B female USB connector.
1) LOW JITTER, LOW PHASE NOISE, HIGH STABILITY OSCILLATORS Most audio interfaces and USB-provided DACs refer the data stream clock to the same USB interface clock, that often suffers a very heavy jitter (short range oscillator frequency variations). Thanks to two quartz precision oscillators used on M2Tech hiFace, clock source for output data stream features a very low jitter. A more stable clock is recovered by DAC S/PDIF receiver; a low jitter produces a very limited sound image distortion and degradation. Phase noise (main responsible for jitter) is also very low: this guarantees a short and long range clock stability, also reinforced by a board supply voltage regulation (e.g. at environmental temperature stability is 2-5ppm approximately, compared to 50-100ppm performed by oscillators normally used on commercial CD players).
2) PROPRIETARY DRIVERS
The standard audio drivers available on the market (e.g. Microsoft Windows operating system) dictated constraints can be overcome thanks to hiFace proprietary drivers: they allow for transferring audio data, maintaining the original file quality without any loss of resolution quality; also, sampling frequency constraints are overcome, while Microsoft and ASIO drivers oblige to operate at no more than 96kHz. When hiFace is used together with a player application such as FooBar (available for free on Internet), you can transfer S/PDIF stream music files to a D/A converter at 192kHz/24bits maximum frequency/resolution, avoiding undesired PC or MAC audio mixer data processing during the data transfer from hard disk to interface. Presently, Windows XP, Vista, Windows 7 drivers are available, as well as Mac drivers for 10.4, 10.5 and 10.6.
3) COMPACT SIZE AND EASE OF USE
M2Tech hiFace features a very compact size and can be directly (or using an accessory USB A-A adapter, not supplied with hiFace) connected to a High Speed USB 2.0 port of any computer. A very high electric and mechanical performance RCA gold connector provides an output signal, ready to be connected to a Hi-End system. No external power supply is required, as hiFace draws its power from USB bus itself and regulates it with its internal regulators. hiFace USB interface connected to a last generation mini PC provided with a High Speed USB port makes for a complete music transport system at very low prices (in the range of few hundreds Euros). Such system allows for listening any density and resolution music files, playing own CD's using a CD ROM drive, obtaining access to more than 10,000 web radio, many of which broadcast their transmissions with CD quality.
Size: 105x46x104mm (w x h x d, case) 105x50x142mm (w x h x d, total)
Sampling frequencies (kHz):
44.1, 48, 88.2, 96, 176.4, 192
16 to 32
USB 2.0, supply, master clock
S/PDIF x2 (RCA & BNC)
I2S (RJ-45). Supply voltage:
7-11VDC (15VDC max.)
140mA (idle, no output connected)
Master clock input voltage:
I2S output voltage:
LVCMOS (3.3V) with 25mA current capability on each line