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It was Euphonic Technology's Michael Goldfield who put me on to the Sony D-7S Discman. "The sound isn't state-of- the-art," he said, "and it's not a candidate for mods. But you'll love it." He was right.

This is the nicest toy I have had since I got my first English bicycle. One of the greatest pleasures is showing it off in front of teenagers, who turn green with envy. Adults, too. Everyone who sees it, and listens, says they want to go out and buy one. And so far, a dozen of my friends and acquaintances have.

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Description: Portable "Discman" player (CD equivalent of Walkman tape player). Frequency response: 20Hz–20kHz +1/–3dB. THD: 0.008%. Dynamic range: 90dB at 1kHz. Outputs: line 1.6V RMS into 10k ohms; headphone 30mW/ch into 32 ohms. Power source: 9V adaptor (supplied), 6V lead-acid battery pack (supplied), 8 AA cells in battery case (optional), or car battery cord (optional). Supplied accessories: carrying case, shoulder strap, signal cable (stereo mini to two RCA phono); headphones not supplied.
Dimensions: 1.25" (31.5mm) by 5" (127mm) by 5.25" (132.5mm) (…

Peter W. Mitchell: The public debut of Philips's digital compact cassette (DCC) was the biggest event at the 1991 CES in Las Vegas…

Since taking over reins and reign at Philips, Jan Timmer (previously head of PolyGram, then head of Philips's Consumer Electronics Division) has given no personal interviews. The only exception was for the official magazine of the MIDEM music industry conference held in January at Cannes, in the South of France.

It would have been hard for Timmer to refuse the MIDEM organizers' request. This year was the 25th anniversary of the event, where record companies, music publishers, distributors, and music-industry trade bodies meet…

How can two channels of 16-bit audio be recorded on something similar to an analog cassette? The maximum bit rate in a linear track of a tape running at 4.76cm/s (standard compact cassette speed) is somewhere near 100kbit/s which, as DCC offers eight parallel tracks, results in a total "space" of 768kb/s. Half of that space is consumed by Reed/Solomon interleaving, synchronization bits, and a 10:8 modulation scheme, so only 384kb/s are available for pure audio information. Now there is no way around Shannon/Nyquist, so in order to maintain 20kHz of audio…

The digital input filter in the DCC's PASC encoder divides the audio spectrum into 32 sub-bands of equal width; but the initial announcement did not specify whether they are equal on a linear or logarithmic scale. I naturally assumed a logarithmic scale, which would make each sub-band about a third of an octave wide, as in an audio spectrum analyzer. But my Boston colleague E. Brad Meyer learned that they are equal on a linear scale.

To clarify the point I called Gerry Wirz, project manager for DCC, at his office in Holland. He confirmed Brad'…

It was with great interest, therefore, that I read Part I of Bill Sommerwerck's monster headphone survey in the March 1991 issue, as well as Gary A. Galo's report on Joseph Grado's HP 1s elsewhere in this…

Measuring headphones is fraught with practical problems, mainly due to the fact that the target response for a drive-unit that fires straight into the ear canal is anything but flat, given the frequency-response–modifying natures of the pinnae and inner ear canal which, as mentioned earlier, are unique for each person. Fig.1, extracted from an excellent 1980 AES paper (footnote 1) from Audio Contributing Editor Jon Sank, shows the envelope of responses he found desirable for conventional headphones to sound flat.

For this review, I measured the responses of…

Many of the results are strange, as democratic theory would predict of any poll that involves many candidates. (It's conceivable, for instance, that the winner of a category might be someone who was nobody's #1 choice: maybe this musician was everyone's #2, but the picks for #1 were so split, among…