cliveb wrote: > Analogue records: distortion is greater towards the centre of the disc, > because the constant angular rotation speed means that there is less > linear space to contain the cut waveform. So it makes sense to start the > cut towards the outer edge, so the minimum amount of the cut occupies > the area where the distortion is greatest. > Of course if you can calculate exactly how much space will be needed for > the side, you could start the cut at the appropriate position so that > the end of the side is close to the outer edge. And when you consider > that many works (especially classical) tend to climax at the end, this > would make sense - the most complex part of the waveform would be > located where the distortion is at its lowest. (In fact I have a vague > recollection that there have been records cut that way in the past).
Hi Clive! Your comments are certainly valid regarding the problem of constant angular velocity (i.e. 33 1/3 r.p.m. for LP's) causing the stylus groove velocity to reduce as the circumference (well, almost!) of the spiral groove is reduced while traversing the surface of the LP. There is of course also the problem of trying to control the correct alignment of the stylus in the groove when using a tangential arm, the effect of which is magnified as the radius of the groove reduces. I have never encountered any discs cut from inside to out, although I agree that many orchestral composers could not resist a grand finale. And why not? They hadn't even dreamt of the possibility of recorded sound, they were writing for live concert audiences. I do know that it was common practice to use an advance monitoring head to detect the amplitude of the next few bars of music, and to use this to adjust the groove spacing dynamically as the master disc was cut: this is why you can "see" the loud & quiet passages when you look almost any large-scale classical music LP. Dave :) ------------------------------------------------------------------------ Golden Earring's Profile: http://forums.slimdevices.com/member.php?userid=66646 View this thread: http://forums.slimdevices.com/showthread.php?t=106914 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
