Since fake news is on everyone's minds these daysI would say it's been in the news a lot, but that kind of reasoning is too circular even for meit's worth keeping in mind that there's also such a thing as fake praise. You see it every day, whether it's a fake Google reviewan alarming number of businesses seem unaware that real people don't actually say things like "the team at New Hartford Chevrolet really listened to all of my needs"or fake trophies handed out to all 20 co-captains of your child's soccer team.
The most notable aspect of Benchmark Media Systems' DAC3 HGC ($2195), which I favorably reviewed in the November 2017Stereophile (footnote 1), is its low noise floor. John Atkinson's measurements corroborated Benchmark's claim that the DAC3 is capable of "at least" 21-bit performance. While significantly less than the theoretical potential of a 24-bit data format, 21 bits is still the state of the art, and corresponds to a dynamic rangethe ratio of the highest achievable digital-domain volume to the DAC's internal noiseof 128dB. That's well above the dynamic range that most power amplifiers can achieve. A good-measuring high-end solid-state amplifier is likely to have a dynamic rangethe highest attainable ratio of signal to noiseof about 100dB ref. its maximum power.
The men behind HDCD (LR: Pflash Pflaumer, Michael Ritter, Keith Johnson
High Definition Compatible Digital® (HDCD®), the proprietary process for improving the sound of 16-bit digital audio, has finally arrived. More than a dozen digital processors using the technology are on the market, and the professional encoder used to master HDCD discs is following closely behind.
The author demonstrating stereo microphone techniques at an English audio show in 1981.
For most people the terms hi-fi and stereo are synonymous, and yet it is clear that there is still a great deal of confusion over what the word "stereo" actually means. There isn't even a consensus of opinion amongst producers of records, designers of hi-fi equipment, audio critics and music lovers as to the purpose of stereo, and considering that the arguments show no sign of diminishing in intensity, it is instructive to realise that 1981 sees both the 100th anniversary of Clement Ader's first stereo experiments and the 50th anniversary of Alan Blumlein's classic patent on stereo.
Do-It-Yourself (DIY) loudspeaker projects are quite common in the UK, where details about several excellent designs, including a recent one by Martin Colloms, have been published for public domain consumption. Stateside, the situation is rather grim, where only an occasional subwoofer project (always popular) makes it into the commercial magazines.
The right thing at the wrong time is the wrong thing.Joshua Harris
The sampling theory formulated by Claude Shannon in the late 1940s had a key requirement: The signal to be sampled must be band-limitedthat is, it must have an absolute upper-frequency limit. With that single constraint, Shannon's work yields a remarkable result: If you sample at twice that ratetwo samples per period for the highest frequency the signal containsyou can reproduce that signal perfectly. Perfectly. That result set the foundation for digital audio, right up to the present. Cue the music.
In an article published in the March 2018 Stereophile, I wrote that critics have been attacking MQA, the audio codec developed by J. Robert Stuart and Peter Craven, by accusing it of being lossy. The critics are right: MQA is, in fact, a lossy codecthat is, not all of the data in the original recording are recovered when played back via MQAthough in a clever and innocuous way. For MQA's critics, though, that's not the point: They use lossy mainly for its negative emotional associations: When audiophiles hear lossy, they think MP3.
When you come to a fork in the road, take it.Yogi Berra
Over one busy week in 1986, Karlheinz Brandenburg laid the foundation of a technology that a few years later would upend the record business. Brandenburg, a PhD student in electrical engineering at the Friedrich-Alexander University Erlangen-Nuremberg, was figuring out how to code digital music efficiently enough that it could be delivered over digital telephone lines. A patent examiner had concluded that what the application proposed was impossible, so over a week of late nights, Brandenburg produced the proof of concept and more. It was another decade before the technologyMPEG-2 level III, more commonly known as MP3would find its true home, the Internet.
Loss is nothing else but change, and change is Nature's delight.Marcus Aurelius
Master Quality Authenticated (MQA), the audio codec from industry veterans Bob Stuart and Peter Craven, rests on two pillars: improved time-domain behavior, which is said to improve sound quality and what MQA Ltd. calls "audio origami," which yields reduced file size (for downloads) and data rate (for streaming). Last month I took a first peek at those time-domain issues, examining the impulse response of MQA's "upsampling renderer," the output side of this analog-to-analog system (footnote 1). This month I take a first look at the second pillar: MQA's approach to data-rate reduction. In particular, I'll consider critics' claims that MQA is a "lossy" codec.
I don't think I've ever seen an audio debate as nasty as the one over Master Quality Authenticated (MQA), the audio-encoding/decoding technology from industry veterans Bob Stuart, formerly of Meridian and now CEO of MQA Ltd., and Peter Craven. Stuart is the company's public face, and that face has been the target of many a mud pie thrown since the technology went public two years ago. Some of MQA's critics are courteousa few are even well-informedbut the nastiness on-line is unprecedented, in my experience.
The problem confronting the magazine reviewer when organising the necessary listening tests to accompany/reinforce the measured behavior of a device under test is complex. There has never been a problem with the measurement aspect; as long as someone has access to the same test gearand full knowledge of the test conditionsthen he should be able to replicate the critic's findings exactly (assuming an infinitely narrow spread of behaviour from sample to samplea rasher assumption with some manufacturers' equipment than of others). However, when it comes to determining reliably the audible (or inaudible?) effects on music program by an amplifier/cartridge/loudspeaker etc. then the going gets tough.
The mice in the walls call summer to close while nets come down and leaves turn dead red, but by the time you see this there'll be holiday music in the air . . . and some generous soul might, just might, sneak a few looks through this issue of Stereophile to see what gifts to buy before the tree goes up and presents are openedand all will be nice!
And what better way to serve those possible givers of audio giftsand, at the same time, honor our hobby's most deserving designers and manufacturersthan with our annual Product of the Year awards?
It's day five of our planned month-long stay à Paris, late April through most of May. My wife is here for workfor me, it's strictly for pleasureand we're enjoying Paris's rich, sensual goodness: food, museums, architecture, coffee, people, food. And yet, earlier today, when we were out for a walkwe've been walking close to 10 miles each day, exploring the cityI realized that my life here has been missing something important.
The issue is this business of "single-speaker" listening and demonstration, which has become fashionable in the UK.
The premise: bringing a second pair of loudspeakers into your auditioning room upsets the sound of the pair you're listening so badly that the first speaker's ability to correctly reproduce the timbre of musical instruments is destroyed. This observation is almost surely correct.