12-30-09: ElizabethThis is simply not true. The best-selling single audio component in history is the Technics SL1210 turntable with over 3 million sold over a 30-year period. Thats 100,000 units per year for three decades; I'd hardly call that a fad. Direct drives disappeared after a decadenot because they were a fadbut because the CD replaced the LP as the primary source of music. The 1st generation SL1200 came out in 1975. CD sales surpassed LP sales in 1987. Thats about a decade. Belt drive survived the CD onslaught because belt drive turntables can be made cost-effectively in small quantities; DD tables need economy of scale. Belt drive turntables are the cheapest ones to make; they require the lowest start up costs provide the highest availability of stock parts such as motors and belts.
Direct drive was a fad. Just like linear tracking arms. The 'cool' factor wore off
after a decade, and everyone went back to the belts and pivoting arms.
Another oddity was 'idler wheel' drive.
Furthermore, idler drive was far from a curious aberration; it was the industry
standard for the first 30 years of LP playback. Nearly every turntable from
that period from market-leading manufacturers Garrard, BSR, and Dual was
an idler drive turntable. It was also the drive of choice for professional
turntables from Rek-o-kut, Garrard 301/401, QRK, Russco, and Loricraft for
their reliable operation, high torque for rhythmic drive, and fast spin-up for
cueing. Even the still-highly-regarded Thorens TD-124 had a belt-to-idler
rim drive mechanism.
Belt drive didn't replace idler drive; direct drive did. I know; I was there when
it happened, managing a couple of audio stores in SoCal in 1975-6. Then in
the mid-to-late '80s most direct drive and remaining idler drive TTs died
with the takeover of the CD, leaving the belt drive cottage industry to survive
in small numbers. The Technics DDs also thrived in the dance clubs as they
were the only turntables still available that were rugged enough and spun up
fast enough for DJ work.