Although it's a bit higher than redline on a typical Honda tach, 24,000 is not really an extraordinary speed for small rotating machines. It is in about the right range for the separator disks in a DeLaval cream separator used on many farms in the early 1900s. They seldom exploded.

24,000 RPM is also "synchronous speed" for a (single pole) electric motor operating on 400 Hz AC power, which is quite common in aircraft, so quite a few electric motors/generators/hydraulic pumps operate at that speed, Some of those are big enough to explode impressively... but don't often do so.

I don't have detailed specs at hand, but one thing to be noted is that there are differences in methods used by various CD drive makers. My impression is that most of them claim to use a "constant linear speed" in one form or another. Rumor is that some early model CD drives used constant rotation speed, and there may still be a few of this kind around.

The CD has to spin at a very consistent and stable speed in order to be read accurately, but that speed doesn't have to be exactly at "playback speed." The disk could be spun up to some lower speed to stuff memory buffers with the bits before the play starts, and as long as reading the track finishes before the buffers are emptied the music will be continuous. Since the bit density (bits per revolution) is lowest at the start of the CD, at the inner track, the buffer stuffing can get a pretty good head start without too noticeable a delay, even if it doesn't spin at the ~500 RPM needed for "real time" data transfer. The controller can hold back on the start of playing a subsequent track until there's enough in the buffer to get to the end of that track, so in a cheap playback drive, the track delay (dead time between tracks) may be slightly longer than theoretically was "recorded silence."

As play progresses to the outer areas of the CD, buffering can also be used to read stuff into the buffer at whatever bit rate the CD produces at that radius, with the buffer output regulated to the rate needed for the playback. This means that it is not necessary to have a different rotation speed at every radius where data must be read, and I've seen descriptions of "stepped speed" drives (advertised as constant linear speed) in which as few as 4 or 5 rotation speeds were used, with each speed used to read a "zone" on the CD, using the data buffer to provide constant bit-rate-out while the bit-rate-into the buffer varies somewhat across the zone.

The "innards" of drives are considered proprietary by the manufacturers, so they don't give out a lot of info on exactly how things work inside a given drive. As long as the signal at the connector meets the specs, it's a good drive and you're not supposed to need to worry about what's going on inside.

But they do definitely spin a bit faster than 78 RPM, even at 1X playback speed.

John