Comments on the
South China Morning Post
Article on Minidiscs

Eric Woudenberg
April 2001

Hi David,

Thanks for writing such an enthusiastic article.

I do wish I had been given a chance to proof-read it for you though, there are several pretty serious inaccuracies.

I point them out below:

The MD is "magneto-optical", which means it is encoded by magnetically aligning crystals heated in the focus of an intense laser. The MD's glory is it combines CD sound quality with recordability - up to a million times on a single disk.

It is called magneto-optical because the information is written magnetically (under laser heating) and read back optically. The record head is aligning magnetic domains in the rare-earth metal alloy recording layer of the disc, there are no crystals involved.

You can re-record on CD-RWs, but this requires a computer to record, and standard audio players can rarely read the discs.

You might have mentioned that CD-RW lacks any editing capabilities other than "delete last track" and "delete all".

MDs, by contrast, are hi-fi components, with hi-fi level sleekness and reliability. They come in two lengths: 60 minutes, and 74 minutes (or double that if recording in mono), the 74 being the length of a standard CD. But a CD can hold 650 MB of digital audio, while an MD only holds 140 MB. So just how does Sony manage to squeeze all that music on to a MiniDisc?

MD blanks come in three lengths, 60, 74 and 80 minutes, double that if you record in mono or stereo LP2 mode, quadruple that if you record in stereo LP4 mode (yes, 5h20m of stereo audio on one MD in LP4 mode). The LP modes have become possible with the so-called MDLP equipment introduced by Sony last September and subsequently produced by all MD equipment manufacturers. This is the biggest thing that has happened to the Minidisc format in years. (You should not have missed this!) See the MDLP FAQ for details:

By using ATRAC (Adaptive Transform Acoustic Coding). This compression format follows a perceptual model of human hearing which ensures an audibly identical copy of the original. The higher the ATRAC version, the better the sound quality. Advanced ATRAC can make MDs sound better than CDs.

I would have said "ensures a copy that is for all practical purposes indistinguishable from the original" and "can sometimes make MDs sound better than CDs". Well mastered CDs with noise shaping (aka Super-bit-mapping) can still beat MDs, they have got just so much more information carrying capacity to encode with.

Adding to the MD's aura of excellence, almost every portable player has shock-resistant memory control. This means you can ride the train, cycle or even jog with one.

Every single MD device, portable or otherwise, has shock memory. You cannot build an MD device without one because you will end up with audible gaps during the periods when the head is seeking to a non-contiguous audio segment. Shock memory is part of Sony's specification for the Minidisc format.

Quite how the MD ever came into being is as mysterious as central China's white mud pyramids. MD guru Eric Woudenberg, editor of MiniDisc Community Portal (, said Sony began developing it shortly before it appeared in the early-1980s.

You are off by 10 years. Sony introduced MD in 1991. See the original announcement: Not only that, you quote me as saying that. Bad.

However, at first the new product bombed. Reasons included initial high cost and that blank disks were hard to come by, while consumers were reluctant to adopt a new product so soon after the advent of the CD and in a market piled with competing digital formats.
Reasons included the high cost and that pre-recorded MDs were hard to come by. Blanks were always available (by mail order at least), just expensive.
But the firewall is by no means obstructing sales. With a little help from Claudia Schiffer's presence in MD advertisements, demand for the product has expanded rapidly. Although it may be too early to sing a requiem for the CD, its time is clearly close at hand.

I think your case for saying that MD will displace CD is pretty weak. But thanks for trying!


Eric Woudenberg

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