MARCO Manunta, M2Tech’s chief technical officer, shares some insights with us on the company’s approach to designing its digital processors.
The computer is increasingly becoming a source component for hi-fi systems. In your opinion, why has it become so popular over the past five years or so?
I think there are three main factors: 1) The turnover in customers platform – more and more young people, acquainted with computers, are buying hi-fi; 2) Music files are easier to buy than CDs or vinyl, as you can just pay for them with your credit card and download them onto your computer, it’s a matter of a few minutes, no waiting for shipping, no going to shops which are almost never provided with what you’re looking for, no returns of defective discs; 3) Music files’ quality often overcome that of music in CDs or DVDs.
Also, we must not forget the increasing bandwidth capability of home links which makes it easier to download huge files. If such a bandwidth was available 10 years ago, in my opinion, computer music would be an established reality today.
We know that computer-based audio is a lot more than just plugging in a 3.5mm jack into the computer’s sound card stereo audio output. What are the challenges you face in designing an interface between the computer and the hi-fi system that performs to the standard expected by audiophiles? What are the inherent problems that you have to address? Could you answer this in respect of: (i) the operating system, both Windows and Mac; (ii) hardware – USB function, in particular; (iii) could you explain more about bit-perfect audio and jitter; (iv) any other factors that you consider crucial?
I see no real difference between operating systems – each one has its limitations and strengths. Major challenges are high sampling rates handling capability, jitter and hidden samples processing. We addressed the first one with proprietary drivers and firmwares in our interfaces. The second one was addressed by letting the interface be master to the host (computer), thus freeing transfer from bad computer timing.
The third one is the most subtle and difficult to address. We managed to have our devices able to work in kernel streaming mode (Windows), thus avoiding the operating system being able to do any unwanted processing, and making Mac drivers in a way that they inhibit Core Audio processing even in normal float mode, thus obtaining bit-perfect operation in both cases.
It must be said that the system’s intrinsic performance is more and more relevant as the sample rate increases; a great system operating at 44.1kHz can be poor when operating at 192kHz, because absolute jitter values are more and more relevant as the sampling period decreases (with the increasing sampling frequency).
What is M2Tech’s philosophy when designing computer-based audio products? What is it the company aims to achieve?
We always design to obtain the best instrumental performance out of a certain design, with regards to budget. Usually, this also pays back in terms of sound quality. We try to keep data processing at a minimum and avoid asynchronous processing as it may generate artifacts in the sound. We choose good parts in critical positions (e.g.: in the Young, we use polypropylene capacitors and MELF non-inductive resistors in the analogue stage, as well as very low ESR capacitors in the power supplies to reduce ripple without increasing the complexity).
Then, we have a restricted panel of expert listeners who help us to refine the design, sound-wise. We don’t want to make “final” equipment – they are generally very expensive and the market is even less willing to accept this kind of equipment. We want to offer very good value-for-money products. Of course, this is not same as “cheap” products. It only means that we don’t want our customers pay for what is not strictly related to their pleasure in using our equipment.
How is your approach different from other manufacturers?
I’m not the person to answer to this question, but maybe some hints can be found in the previous answer.
Please tell us more about the new Vaughan DAC – what are the improvements that have made over previous products that justify the significant increase in price?
For sure, the DAC section, with the array of ICs driven in time-shift fashion. Then the supply, with the large-capacity battery and the dedicated battery charger. Again, the comprehensive input range, the headphones output and the remote control.
More in detail, we made I-V converters using ultra-high quality op amps, with an extensive use of polypropylene capacitors and MELF resistors in all the conversion and analogue stages. The digital volume control operates on a very large word arithmetic, so no truncation distortion is heard, even on very low levels.
Anything else you would like to share with our readers?
Two things – 1) We are serious about designing, manufacturing and marketing our products. This leads to products which are maybe more expensive than some competitors, but also have an added value in terms of applied research and intrinsic design quality, which in turn give benefit to the sound. Our cabinets are filled with carefully-thought designs. Moreover, our products are entirely made in Italy. 2) Stay tuned for the new products to come soon!