Just keep in mind folks, that when you’re ascribing characteristics to a material (whether it be acrylic, PVC or aluminum), making an apples to apples comparison is difficult to do if you’re comparing platters of identical dimensions.
You won’t know if the differences your hearing relate to the mass difference or the material’s sonic characteristics.
Higher mass may a sonic effect with respect to how the bearing’s thrust interface is loaded (for better or worse, and affecting energy transmission).
More importantly, higher mass will in general, smooth out the drive system’s speed characteristics, and you "hear" the effects of speed instability in ways that are much more subtle than pitch stability, wow and flutter, etc. At it’s finest level of granularity, micro levels of speed instability are experienced as IM distortion.
Looking at it from the other side (improving these micro-instabilities), you'll get a cleaner rendering of high frequencies, as well as more extended highs and (surprising to many) a richer harmonic presentation in note fundamentals (think bowed double bass and cello).
If you have the time, wade through the first page of Moncrief’s review of the Rockport Sirius III on IAR. Moncrief is a strange dude, but he lays out the situation fairly clearly in this regard (albeit in a very wordy manner). At a minimum, it will cure your insomnia ;-)
Having said all of this (in the VPI universe) you’re obviously left with the decision as to whether platter "A" works better for you than platter "B". I didn’t mean to imply otherwise. Just be careful about generalizing your conclusions with respect to materials.
Cheers,
Thom @ Galibier Design
You won’t know if the differences your hearing relate to the mass difference or the material’s sonic characteristics.
Higher mass may a sonic effect with respect to how the bearing’s thrust interface is loaded (for better or worse, and affecting energy transmission).
More importantly, higher mass will in general, smooth out the drive system’s speed characteristics, and you "hear" the effects of speed instability in ways that are much more subtle than pitch stability, wow and flutter, etc. At it’s finest level of granularity, micro levels of speed instability are experienced as IM distortion.
Looking at it from the other side (improving these micro-instabilities), you'll get a cleaner rendering of high frequencies, as well as more extended highs and (surprising to many) a richer harmonic presentation in note fundamentals (think bowed double bass and cello).
If you have the time, wade through the first page of Moncrief’s review of the Rockport Sirius III on IAR. Moncrief is a strange dude, but he lays out the situation fairly clearly in this regard (albeit in a very wordy manner). At a minimum, it will cure your insomnia ;-)
Having said all of this (in the VPI universe) you’re obviously left with the decision as to whether platter "A" works better for you than platter "B". I didn’t mean to imply otherwise. Just be careful about generalizing your conclusions with respect to materials.
Cheers,
Thom @ Galibier Design