VPI Aries w/SDS and Flywheel SetUp Question


Just added a flywheel to my Aries t.t. and it seems to make my platter turn too slow. (Music sounds slow compared to CD of same)

I have an SDS and trying to use the strobe disc, but have to go way up in frequency to compensate.... like from 60hz to 62.8hz. To get the disc to look right... but then the music sounds bad. When adjusting by sound, I'm at about 60.8hz, but the strobe disc looks way off. What's up? Are these numbers way out of normal parameters?
jbatlanta
Problem Solved!

In talking to VPI, they told me the VOLTAGE on the SDS has to be changed when adding the flywheel. (I don't see this in the manual for the SDS....and I didn't get a manual with the flywheel)

Makes sense. There's more mass to turn, and the SDS is programmed to reduce voltage once the platter is up to speed. Analogy would be running a car too slowly in high gear.

Well now that I've bumped up the voltage, Steely Dan's "Gaucho" and also the Doobie Brothers record all sound the same pitch as the CD. (I used several 'duplicates' of records and CD's to compare).

This record thing requires work, doesn't it!

John
Although I don't own a VPI turntable (I'm one of those "Linnies" with my LP12 turntable), I have defied one of Tiefenbrun's laws by going "back to basik"(motor, that is) and buying a VPI SDS power supply instead.
VPI flywheel issue aside, as for your comment regarding the record sounding "correct" at the 60.8hz vs the "strobe-correct" 62.8? It could be quite possible that your "comparable" CD was either mastered too slow or the original LP too fast? Just curious, what LP were you using for the comparison? As I heard firsthand, Gerry Rafferty's album suffers from such a fate(the original US issue w/ Baker Street was mastered too fast, thus making the CD reissue to sound "slow" by comparison). That's why the VPI SDS is truly important for the archivist and listener alike, for correcting such mistakes. My thoughts.
........Paul
I've been playing around with the belt tensions by moving the motor and flywheel this way and that, and surprisingly that seems to make a difference.

Bumping the frequency around also on the SDS while comparing to the sound of CD player (same album) and matching by ear has worked, also.

Personally, I think with the platter being that heavy, it is a 'flywheel' itself. Why add another? I did it, cause it looks cool and fills up the space on my Symposium Ultra platform better...... but, I'd take it off if it was sonically bad, for sure.

Anyone else using the flywheel?
I also have the VPI Aries with SDS and added the flywheel later. I could never get the unit to sound right with the flywheel installed. Upgrading to the SDS made a huge improvement in the overall sound, but, IMHO, the flywheel didn't do any good. As soon as I removed the flywheel from the setup, the sound returned to normal. VPI took the flywheel back - they have great customer service. Just my 2 cents. Good Luck with this!
Your strobe is probably off. Someone recently had a very good suggestion. Put a piece of tape on the platter and count the rotations for a 3 minute period. It should be 100. Adjust your speed accordingly. I thought this was a great suggestion. For more resolution go for 6 minutes for 200 revolutions.