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If I remember well, a company has already done this for CD-ROM, it was reading several track at the same time, they had a commercial product but I don't know if it sold well.

That would be Kenwood Tech and their TrueX drives. Seems a nice idea since they probably don't sound like an airplane taking off like other high-speed CDs do, but they had a high failure rate on their first ones that I don't think they ever lived down. It's too bad they didn't license the tech rather than trying to build it themselves.

You can find their TrueX pages on google, but their home page announces that they've stopped making the drives.

unless materials used for cd's change, there is an upper limit to this cd x speed madness...

That depends how you're rating CD speed. If you mean the spin speed, then you're correct, but if you're referring to reading speed then there are ways around it.

Kenwood has has had TrueX drives out for ages now. Their latest version reads at 72x the original 1x rate of 150K/s, using multiple lasers to read in parallel. Strangely, the page seems to suggest they've stopped producing them, but I can't imagine it's the last we'll be seeing of that idea.

I'd like to see the multiple-laser technology used to produce quieter drives, even if it means the read speeds are lower. My existing 40x CD drive makes a hell of a lot of noise, especially if the CD isn't perfectly uniform.

Well, I assume the technique had some problems (Zen Research seems to be down for the count) and would have to be adjusted to work with CD-R, but isn't the idea behind TrueX (which Kenwood used for quite a while) a potential work-around now that noise and safety are becoming issues?

They used a diffraction grating to split the beam and read mutliple points on the disc at the same time. That freed them up to spin the disc slower to reduce noise and jitter. It also meant they could read at a consistent speed across the entire surface of the disc. Not to mention greatly reduced spin-up times.

This wouldn't work as-is for burning CDs because you're turning on and off the laser, which would mean all the "split" beams would have to be writing the same thing. But how hard would it be to put in a second laser, spin the disc at 32X and get 64X burning with less noise and no safety issues? Anyone know why TrueX failed and if / how it could be adapted to CD-R?

I heard that many people had reliability issues. Kenwood appears to have discontinued theirs, even though it's the only product listed on their computer peripherals page. I think their webmaster needs to wake up!

I heard that many people had reliability issues. Kenwood appears to have discontinued theirs, even though it's the only product listed on their computer peripherals page. I think their webmaster needs to wake up!

Zen Research has developed a technology that reads the disk using 7 beams in parallel, achieving high throughput without spinning the disk at ridiculous speeds.

It has been licensed by several companies including Kenwood that used it to produce an amazing 72x drive.

The Kenwood 72x drive is quite fast.

What it does is to spin the drive slower, but read 7 tracks in parallel. Now if they could get two read heads like this, it would be a 142x drive without having to spin the cd any faster.


Here's the info.

http://www.pctechguide.com/08cdrom2.htm

or

http://www.kenwoodtech.com/72x_atapi.html

-Eric

Kenwood made a drive that does this. It spins at around 10x and reads at 72x. Unfortunately, they have discontinued it.