Exclusive interview with dCS



Where and how did it all start for dCS?

In 1987, the Converters group at Cambridge Consultants Ltd. left to form Data Conversion Systems Ltd. The group’s expertise was in high resolution ADCs/DACs for demanding applications such as military radar systems, test equipment, chip design and digital audio. In 1996 dCS decided to specialise in pro audio / consumer audio products and move away from consultancy work. This move saw dCS develop a number of digital audio world’s firsts such: 24/48 & 24/96, followed by 24/192, DSD & 24/384 in the following years.

Would you consider dCS an audiophile oriented company?

dCS is definitely a consumer audio company now, no longer a consultancy or a pro-audio manufacturer. For a variety of reasons, we stopped making pro audio equipment in 2008 and our production is now solely audiophile equipment and our products improve every year.

Kindly list all of the present products from dCS.

Scarlatti series: DAC, Upsampler, Clock and CD/SACD Transport.
Paganini series: DAC, Upsampler, Clock and CD/SACD Transport.
Puccini series: CD/SACD Player and USB-Clock.
Debussy USB DAC.

dCS is a synonym for great executed digital converter and players. What is the secret behind it?

Firstly, the dCS Ring DACTM is a discrete balanced design that runs at a very high sample rate with 24-bit performance and does not use any proprietary chips. This means it does not have the limitations imposed by DAC chip technology, so we could keep doubling the sample rate through the 1990s and early 2000’s. Our Ring ADCs use the same principle.

Secondly, the dCS Control Board is like a digital audio PC – we can change its function completely by loading different software. The same board is used in DACs, ADCs, DDCs (Upsamplers), Master Clocks, Transports, Players… and even test equipment. (When the company started, commercial audio test equipment was limited to 16/48). The whole system is controlled by software that is written in-house, so we can optimise the performance.

You don’t implement any tubes, but only solid state. Why is that?

The roots of our audio products are in the pro arena, where converters MUST have a respectable measured performance and be reliable. This cannot be achieved with tubes in the signal path. Over the years, several people have tried to tell us that we are making a mistake by not using tubes – the continuing success of our products suggests that we have the right idea after all.

Have you ever even thought about implementing tubes into your products?

We have tube expertise in the company and we do receive requests from pro customers occasionally so never say never but for now there are no plans.

What is your approach and specific to your topology?

Everything presented to a Ring DAC is oversampled, noise-shaped and converted to 5 bits at either 2.822 or 3.07MS/s. This arrangement gives 24-bit performance in the audio band, low noise and a frequency response that extends beyond 100kHz.

What does state of the art digital audio actually mean for dCS?

Our aim is to design a digital front-end with the closest approach to a top-end analogue system, but without the noise penalty, bulk and steady media degradation of vinyl.  State of the art digital audio to us means that the entire chain from recording to mastering to playback must be state of the art with ultimate fidelity as the priority. Unfortunately this is rarely achieved.

Do you think balanced topology is a must for best sound?

Balanced topology inside a DAC is essential to cancel out switching artefacts and reject interference from the digital circuitry.  Balanced analogue interfaces are a valuable tool for ensuring clean transmission to the power amplifier. Many amplifiers do not have balanced inputs, so we provide high quality unbalanced outputs also.

What set dCS audio design above other manufacturers?

With few exceptions (e.g. CD mechanisms), we do not have to rely on other manufacturer’s solutions – so we have the freedom to design the product in the best way we can. After all these years, the Ring DAC is still a major asset and everything inside a dCS unit is designed with ultimate performance as the objective.

Do you use pure class A in your signal chain?

Yes – the Ring DAC core operates in pure class A mode, as does our discrete balanced output stage. The rest of the analogue circuitry also operates in class A while it is lightly loaded.

What is your approach to power supply and how important it is in your opinion?

Power supplies are extremely important. We use one or more mains transformers for safety isolation, followed by DC-DC converters for cooler running, followed by linear regulators for low noise. Critical circuitry, such as the clock generator and the Ring DAC reference, has multiple stages of regulation.

Do dCS components need or benefit with outboard power solutions?

Power for our products is generated from 12V DC, so battery operation or separate power units would not be difficult to arrange. We make a 4-box digital front end, so a fifth box would be hard to accommodate. The improvements over a simpler system (e.g. the Puccini Player) are largely due to separation of functions, so adding a separate power supply option may well be worthwhile.

What importance do you give to the built in elements? Are they crucial to your approach or do you find tuning them in the right combination to be of the most importance?

The choice of high quality parts is essential to good sonic performance. To this end, we use metal film resistors and polypropylene capacitors in critical positions. The analogue path is entirely direct-coupled – there are no coupling capacitors that might add a sonic signature. Selecting crystal oscillators that have excellent phase noise performance is an ongoing process!

Even the latch chips used in the Ring DAC core are carefully chosen for consistency.

Lot of audiophiles find your electronics as match made in heaven for classical music. Why is that? Transparency?

dCS’ specialty is delivering the ultimate in Musicality and by this we mean:

Melody and harmony. These are the keys to musical beauty and our systems possess the ability to play simultaneously several harmonically related notes (a chord) and preserve all of the information on the recording.

Playing the note at the right time. A great Hi Fi system needs to accurately convey this aspect of performance. Without this a recorded performance can sound anything from bland to unfathomable.

With the note at the right volume. Very few Hi Fi systems achieve a true wide dynamic range. Real dynamic range encompasses the ability of the system to simultaneously reproduce a loud instrument and a quiet one. With dynamic range comes insight into interpretation, a slight emphasis on a note in a bar implies a rhythm and feel that is easily lost in most reproduction systems. The ability to convey complex rhythms passed around many disparate instruments is beyond most systems at any price.

We see the job of a Hi Fi system being to preserve the subtle information on a recording through the reproduction chain and present it to the listener with all of the emotional content intact. Looking at musical reproduction this way is what dCS is all about and in our opinion is achievable only by the finest music reproduction systems.

It seems, that contemporary digital audio moves towards details, speed, transparency etc.  Where is the line between resolution and musicality?

Opinions will vary, but our listening tests suggest that musicality really starts to suffer below
about 20 bits. More bits in the recording means more information is captured and (if the DAC is capable) results in more detail.

A higher sample rate is also a major factor, as more samples makes it easier for the DAC to reconstruct the original waveform. This also adds detail and transparency to the sound.

Where do you think everything will stop with sampling frequency and bits?

Computer infrastructure is the limiting factor. We pioneered 24/192 in 1997, but it has only been in the last few years that native 24/192 recordings are available – and even Windows 7 does not support this format without special drivers.

We developed the first DXD (24/176.4 or 24/384) converters in 2004, and heard some really remarkable performances just from upsampling SACD data to DXD. Unfortunately, the pro audio industry regarded this as a step too far and most showed little interest. It is good to see companies like 2L releasing native DXD recordings. This is the obvious next step.

Do we need 32-bit digital recordings? 

Only if we can develop TRUE 32-bit ADCs and DACs.

A 24-bit DAC that “does something” with the last 8 bits is not the same at all.

Word length will probably extend to 32 bits “because we can” rather than because we need more than perhaps 28 bits. True native 32/384 would be fabulous. I can dream…

We use double-DXD as an intermediate stage inside our DACs, so we could take the next step at some point, if there was a demand.

Some people from industry say that digital audio era is only approaching us. Do you think that great digital is the future or is it already here?

Its already here in terms of technology. The software, hardware, bandwidth, storage space is all available to provide fantastic digital audio playback. The real bottleneck is high quality music being easily available.

Please tell us more about your CD and SACD player?

The Puccini Player is housed in an aluminium case fronted by an anodised aluminium front panel that has been sculpted from a solid billet. The case is reinforced with sound-deadening material to help reduce vibrations.
The Player uses the same Control and Ring DAC boards that are used in our Scarlatti and Paganini stacks – except that all the functions are performed by one set of boards in one box. The CD mechanism is the same as that used in the Paganini Transport – Esoteric UMK5. The Puccini will obviously play CDs and SACDs, optionally upsampling the CD data to DSD before conversion by the Ring DAC. There is direct access to the Ring DAC via two SPDIF inputs, supported by a separate word clock input. A license code (supplied free when new units are registered with dCS) turns on the DSD upsampling feature for the digital inputs (this is in addition to our standard PCM oversampling processes).

The Player is a formidable product in its own right, but the addition of the matching Puccini U-Clock adds another dimension to the sound quality by improving the Player’s already very low jitter level even further and providing a gateway for high end performance from a computer source.

The U-Clock features our asynchronous USB to SPDIF converter, which can pull data from a computer under the timing control of the clock section – breaking the link to the computer’s jittery clock. The SPDIF output plus a word clock feed can then drive the Player’s ring DAC. This combination gives excellent results when driven from any recent Mac or PC (or another digital source).

I guess you also don’t think that CD’s are obsolete, or?

Most of our customers have large collections of CDs (1000+ is common), and many are reluctant to change to hard-disc-based storage. We have always regarded optical discs as a means of streaming digital data to our converters – and no more than that. We will continue to support CD and SACD playback for as long this is economically feasible.

All 4 of our product ranges have supported computer audio for some years, so the demise of the CD will not be a problem for us.

Do you produce everything in house or do you employ subcontractors?

dCS is a small company (there are 15 of us at present), so we have to subcontract the manufacture of boards and metalwork – but always to our design. The hardware & software are designed in house, we do programming, final assembly, test and shipping.

Do you still believe in traditional European quality?

We know that we can source what we need in the UK – albeit at a high price. Our suppliers are close to visit in one day if there is a problem or a new concept or process that needs to be worked on.  We have tried sourcing some small metal parts from the far east – the samples were perfect but the production run was unusable. It seems we have to pay for the care taken in manufacture.

Audiophiles seems to rank you among finest manufacturers and we often see dCS in the best company in the high-end audio fairs.  What is the difference between let us say German approach and a British one in your view?

This is hard to answer because we have never been a German manufacturer!  :o) We make sure the science is right, test and then listen. We try to keep an open mind when we discover an effect that improves the sound, even if we cannot rationalise it scientifically. For example, the dCS Upsampler provides sonic improvements that are obvious to most listeners, but conventional sampling theory indicates it should not make any difference.

What is it that you would say that set dCS audio from competition?

The incredible flexibility of our hardware and software allowed us to take huge technological leaps that others could not.

What is exact dCS audio/sound approach?

Our aim is that every product we make will be the best in its class.

Do you ever plan to bring amplification to your line?

Our new factory that we moved into in June 2010 provides the space we need to consider amplification seriously.

Can you elaborate on special and innovative approaches that you use with your converters?

The Ring DAC takes 5-bit binary data at 2.822 or 3.07MS/s from the Control Board. The data is decoded into 32 individual lines which pass through a randomiser (which breaks up patterns in the errors). The data is clocked into a large array of latches, which drive balanced currents into a balanced summing amplifier. The amplifier converts the currents to voltage, rejects unwanted common-mode artefacts and filters out the noise above 100kHz. This leaves a balanced, very high quality audio signal.

What is the secret of dCS audio rising presence in high end audio world?

As I said before our aim is that every product we make will be the best in its class. This combines with the 21+ of leading edge experience in digital audio means that we are well placed to keep on pushing the boundaries of digital audio.

Would you say that high quality is more affordable today or you have to pay premium price for best components and sound?

Mid-range audio products are steadily improving as technology marches on. Designing and manufacturing the very best equipment in relatively small numbers is expensive and will probably always be so.

Where does hifi stops and high end comes in for you?

That point is reached when you can sit back, enjoy the music, almost believe you are with the musicians and experience that moment when there is only the music.

What is the future of digital audio and where do you see dCS in it?

The idea of “cloud storage” has some obvious advantages, but also some risks. Will your private music library on a server in a low-cost location be wiped out by a solar flare or a tsunami or a clerical error?

Music on demand services such as Spotify are proving popular, but at this time are only CD format or lower at present. High-res on demand is only a matter of time.

Regardless of where the music is stored, we expect the typical resolution will continue to increase and that dCS will be providing top quality converters, whether they output digital or analogue.

Are physical medium obsolete?

The market is heading that way. We are seeing a trend away from Transports/Players towards USB-equipped Upsamplers and DACs.

Downloading quality music is becoming common, and music shops are rapidly disappearing from shopping centres.

Do you think analog master tape quality can be matched within the digital domain?

Magnetic tape uses a finite number of magnetic domains to store an analogue signal, so even tape has a built-in resolution limit just like digital audio. (Similarly, vinyl discs are limited by the finest detail the cutter can make in the groove.)  I suspect that DXD, or possibly the next step on from native DXD, will exceed the performance of tape.

What is the difference between audiophile and pro oriented products?

Our previous generation of audiophile products used the same Control and Ring DAC boards that were used in our pro range. The main difference is in features and interfaces.

Our audiophile products are easy to set up, they have IR remote control, 1394 interfaces for DSD and a simplified menu structure.

Our pro range is intended to be set up by experienced studio staff. The remote control is by RS232 only, they have multi-wire pro interfaces such as SDIF-2 or Quad AES which can mis-connected easily and the menu structure is more complex to include features an audiophile would not use.

We hear many theories on importance of master clock. Can you tell us more about dCS view?

Good clocking is as important as clean data! You need both for world-class digital sound.

Nearly all digital audio components have a clock generator inside but which is the best source for the system master clock?

In conventional Transport + DAC systems, the DAC extracts the clock from the Transport’s data stream. You can improve this somewhat by adding a word clock link from Transport to DAC, but listening tests indicate that the Transport is the worst point in the system to generate the master clock. This is probably due to magnetic interference from the motor and power supply modulation by the motor currents.

You can improve the sound appreciably by using the DAC as the master clock and locking the Transport to it through a word clock link. Here the DAC is not trying to lock to anything and its internal clock can be quite clean, limited by interference from the DAC circuitry. Common sense suggests that this should be the best arrangement.

Now add a Master Clock unit to the system and lock the other units to it. The sound stage blossoms out even more, the music acquires more detail, delicacy and air. Here the Master Clock unit has a relatively simple job to do – generate a clean clock and do nothing else, so there is minimal interference. This clock signal is more accurate than the clocks inside the other 2 units, but more importantly, it has much lower jitter. Jitter is the bane of good quality digital audio. The Phase-locked-loops in the other 2 units lock to the clock and filter out jitter inherent in the word clock cable/interface, resulting in an even cleaner clock inside the unit.
Yes, it is a confusing subject, but it is hard to argue with the listening tests.

What do music lover gets with adding upsampling? Is this not just another processing in chain?

A separate Upsampler is difficult to justify. Sampling theory indicates that the Upsampler should not make any difference, as the DAC’s oversampling deals with this function.

However, it is easy to demonstrate to anyone with an open mind and reasonable hearing that progressively upsampling CD data to 24/44.1, 24/88.2, 24/176.4 and then DSD makes incremental improvements in fine detail, spaciousness and image depth. The final step is to return to raw CD data – then my rapt audience jerks in shock and asks “what went wrong?”

It seems that dCS is getting stronger this past few years. Why?

Its a real team effort and a result of some very talented people helping to develop and deliver great products that perform to the highest level and are also extremely reliable.  We also like to think that our approach to customer service means that dCS customers are loyal to the product and enjoy being part of our community.

What is high end reproduction for you?

High end reproduction should allow the listener to forget about the technology, sit back and enjoy “Only the Music”.

www.dcsltd.co.uk


Matej Isak: text
Mono & Stereo high-end audio magazine
May 2011, All rights reserved
mi(at)sgn.net
matejisak(at)gmail.com