BENCHMARK MEDIA: Howard Popeck speaks at length to people with interesting things to say: John Siau – Benchmark Media DACs

Originally published 2014

John ... in the audiophile world Benchmark Media have entered quickly and built a terrific reputation from scratch. Very impressive. However from your perspective, how do you see the differences between studio buyers and audiophile end users?

The short answer is that audiophiles talk more. Audiophiles are passionate about their love for music and music reproduction. Studio buyers share this passion, but rarely have as much time available to discuss the details of their audio chain.

The long answer is that Benchmark has made two market transitions:

We began 25 years ago by manufacturing audio equipment for television networks. These networks have hundreds of audio devices in the distribution chain and we specialized in building audio distribution amplifiers that could be cascaded with minimal damage to the audio. To achieve these goals we built products that measured +0/-3dB 0.1Hz to 500 kHz, with THD+N less than 0.0003%, and with a SNR of 125 dB. Our goal was to build the highly-transparent audio products that the television networks needed. They needed this performance so that they could achieve reasonable performance through extremely long and complicated audio chains.

We expanded our operation by introducing extremely transparent audio devices for studio applications. These included microphone preamplifiers, D/A converters, and A/D converters.

Finally we began selling our professional D/A and A/D converters to audiophiles who appreciated our intense emphasis on sonic transparency.

Are you a DAC chip maker and if so are your chips made to your specification i.e. proprietary – or do you buy third-party off the shelf so to speak?

We are not a chip maker but we have participated in the design of DAC chips, SRC chips, and Op-Amps. We have a close working relationship with the manufacturers of these chips. We let them know what we need and why we need it, and for the most part, they have been very responsive. We have had significant influence on the development of a number of audio ICs.

Is microphony, (currently a big issue in the domestic audio world) a fact, or merely conjecture – or perhaps a bit of both?

Microphony can be a major issue in audio products that use valves, but it can also be an issue with certain passive components. A gentle tap on the chassis will usually reveal a microphony problem – if one exists. No music should be played during such a test, and the playback gain should be gradually increased as the test is conducted. In such a test, microphony will disturb an otherwise quiet noise floor as the unit is tapped or vibrated.

How do you protect the performance of your DACs from the impact of microphony in high sound pressure environments?

Before any product is released to market, we subject it to very high levels of vibration while listening to the noise floor and while viewing the noise spectrum on a high-resolution audio analyser. Any disturbance in the noise floor is an indication that a microphony problem exists. We also tap each component with a ceramic probe while listening to the noise floor. Benchmark products are not microphonic and can be used in high sound pressure and/or high vibration environments without isolation accessories.

On the assumption that the primary objective of a Benchmark DAC is that it should neither add nor detract from the original signal, how can you determine that this goal is being achieved at the analogue stage? Or put differently, assuming that any analogue circuit must surely add it’s own sonic signature, however small, how is the extent of that signature determined?

Our products are designed to achieve sonic signatures that are below the threshold of hearing. In other words, our goal is to produce products that have total error signals that never reach the threshold of hearing at normal playback levels. In our products, THD, IMD, noise, jitter-induced distortion, RF-interference, power-supply hum, and microphonics are held to levels that are 115 dB to 150 dB below the level of the audio signal.

Phase and frequency response errors can contribute to sonic signatures and for this reason we design our analog circuits to have a 0.1 to 500 kHz 3dB bandwidth.

The up sampling system used in the DAC1 converter frequency-shifts the digital filter that is built into the D/A chip and replaces it with a higher performance filter. High-frequency D/A images are reduced to inaudible levels.

Currently, what is the limiting factor on the performance of a DAC? Is it the chip, the power supply or should I mind my own d**n business?

In a well-designed system the DAC chip is the limitation. Anyone who is building “high-end” products that are limited by power supply performance should find a different “d**n” business.

Many DAC products are limited by the performance of the analog output stages. Other DACs are limited by the performance of their clock system. In my opinion, these defects are inexcusable in a high-end product.

Many good systems with good DACs are limited by the performance of the volume control system. Much of the success of the DAC1 family is due to the high-quality analog gain control. Competing systems often use digital volume controls that significantly reduce dynamic range.

Now, a little bit of well-intentioned levity if I may. If Benchmark Media were a automotive company, then which automotive company would you choose to be?

Mercedes or BMW – well engineered, form follows function, high-performance, reliable, and worth the extra cost.

We are not a mass-produced economy brand, nor are we a “cost-is-no-object” exotic brand. Personally I have always driven German cars and American trucks. I like the performance of German cars and I like the no-nonsense durability of American trucks. I am not a fan of vinyl tops, imitation wood, chrome wheel covers, and other such nonsense.

Another car that I have admired is the original Morris Mini. In 1959 it introduced a number of innovative technologies that are now common in today’s automobiles. The Mini’s transverse engine, front-wheel-drive transaxle, and efficient use of space inspired several generations of front wheel drive cars beginning with the VW Rabbit.

In 1966 the Mini surprised the world by placing 1st, 2nd, and 3rd at Monte Carlo against exotic “high-performance” cars before being disqualified by the French for “non-conforming” headlights. The Mini demonstrates how innovative technologies can trump a brute-force cost-is-no-object approach to engineering.

The DAC1 introduced UltraLock™, an integrated analogue volume control, a zero-ohm headphone amplifier, ground-breaking performance, all in a compact, rugged, and affordable package. The Mini blurred the barrier between the family car and the sport car. The DAC1 has blurred the barrier between high-end hi-fi and professional audio.

Now getting back to the nitty-gritty, you make a point re your Jitter-Immune UltraLock™ Clock System. What’s not clear to me is how the effects of not having this might be heard by the musically-inclined layperson. So, imagine if you would please a Benchmark DAC demo alongside another notable brand of DAC but without your Jitter-Immune UltraLock™ Clock System. What differences should they hear right away, or should they look for?

Jitter-induced distortion produces sidebands that tend to fall in the middle of the audio band. This distortion clutters the midrange and obscures musical details. The first impression that many have had when listening to the DAC1 is that it has a dip in the midrange frequency response. The DAC1 will often sound like it has less midrange than a DAC with a jitter problem even when both DACs have ruler-flat frequency response.

This initial impression soon gives way to an appreciation for the open and detailed midrange delivered by the jitter-free UltraLock™ clock system. The missing midrange is jitter-induced distortion!

Is the fact that as far as I know, none of my Benchmark DAC owners have ever used the headphone outlets even though they use headphones surprise you?

In a word ….. yes!

The HPA2™ headphone amplifier may be the cleanest headphone amplifier available. The output impedance is well under 1 Ohm to insure tight control over the drivers for low-distortion and accurate frequency response. I strongly encourage DAC1 users to explore the capabilities of the built-in HPA2™. The HPA2™ removes the harsh sound from 45-Ohm headphones such as the Sony MDR-V600 and even improves the distortion performance of much cleaner headphones such as the 300-Ohm Sennheiser HD 650.

The HPA2™ has the power to drive low-impedance headphones cleanly, and it has the headroom required to drive high-impedance headphones. All headphones benefit from the extraordinary damping provided by the near 0-Ohm output impedance.

If I could wave the proverbial ‘magic wand’ then form my perspective the ideal Benchmark DAC would be an HDR but at a cheaper price because of the removal of the headphone facilities. But I guess the retooling costs would be prohibitive, right?

The HPA2™ and the DAC1 share a power supply, chassis, gain stages and other expensive components. Removing the headphone buffers and jacks would not result in a significant price reduction. The high-performance built-in HPA2™ is included at a cost that is far less than the cost of a stand-alone HPA2™ headphone amplifier, but with all of the performance of a stand-alone unit.

Rumour has it that our own BBC uses Benchmark Media products. Is that true and if so, what’s the story behind that coup please?

We have been building audio products for television studios for 25 years. The BBC has been using our products for many years.

Okay, time for an admission here on my part. Rarely have I heard significant differences between RCA connection and optical connection in any DAC let alone my own Benchmark one. Have you heard these and if so, how would you characterise those differences?

We do not believe there is a difference when using a DAC1. The Benchmark UltraLock™ system attenuates the jitter to insignificant levels and consequently both interfaces deliver the same performance through the DAC1. However, digital connections can be an issue with some products.

These differences can be measured on products that lack good jitter-attenuation systems.

Contentious I know, but have you heard sonic differences between competing RCA interconnects of the same length both into and out of any of your devices and if so, did those differences translate into improvements for you?

The Benchmark UltraLock™ system insures that digital cables have no effect on the sound.

Analogue output cables can attenuate high frequencies if they are too long, or if they are driven with high impedances. Our RCA outputs have very low impedance 30-Ohm drivers. We have published a chart in the manual that shows a maximum recommended cable length of 1,360 feet for a loss of 0.1 dB at 20 kHz.

Given the apparent commercial failure of DVD-A and the less than stellar success of SACD, is their situation a sonic tragedy for the end user and if so, why?

No, these formats have serious shortcomings. I never liked the slow loading and menu navigation on these products. CD’s play when you put them in the machine. I shouldn’t need a video screen to navigate the disk – bad idea for audio. High-resolution downloads are the answer. Files can be served from computers, digitally connected iPods, and similar devices without the possibility of data errors that can occur when reading any of the optical disks. In the near future, nearly all recordings will be sold and distributed electronically. All disk formats will die. I predict that the last disk format to die will be the 33-RPM LP.

From your view atop the digital mountain, is there life left in the venerable Red Book CD format – or is it dying a slow death?

The CD is terminally ill.