[net.audio] RE * Half speed mastering

ili (04/13/83)

	Half speed mastering means that the lacquer master is cut at
half speed.
	Normal mastrering is done in real time. That means that the master tape
moves at the same speed it did during the initial recording and the lacquer
master spins at 33 1/3 RPM.  Half speed mastering means that the master tape
and lacquer are both spinning at half speed.
	By halving this mastering speed the power required to drive the
cutting head is reduced by a factor of 4.  Power amp loads are thus reduced
and can operate more linearly.  The cutting stylus can now more accurately
trace all the nuances in the music, keep the distortion low, reduce crosstalk
between channels etc.

Ira Idelson
American Bell

newman (04/15/83)

To me the best thing about half-speed mastered disks is that the frequencies
presented to the cutting stylus are halved, resulting in a vastly cleaner
high end. Nothing bugs me more than a mushy, harsh high end, especially
noticeable as shattering on cymbal crashes on either rock or classical pieces.
Does anyone know for sure whether this breakup is attributable to overdriving
the cutting stylus/driving amps or to poor master tape recording levels? That
is, is it unavoidable to have such a rotten high end on full-speed disks? Or
is it a problem that arises during pressing?