VPI Classic 3 - speed problem

[Maks]

Does the RPM app support 78?

[jbaudio68]

Originally Posted by PMCH

John, I would be terrified to place anything on my platter in case it went flying off and damaged anything. My Classic 3 only came with one belt also. I use a SDS so my speed is easy to set with a strobe disk or digital tach. The SDS allows changing between 33 1/3 and 45 without moving the belt. Hope your speed problem works out.

Fellow Classic 3 owners: I'm not 100% sure but fairly confident that the black rubber traction rings on the metal rim you place in the album (not sure what it is called) are spare tt rings. They look about the same size.

[jbaudio68]

Originally Posted by Alberto

John, Assuming the test LP and app you are using are accurate, the 0.2 variation in speed (~0.6%) is about 6 times higher than the specs (see below). 1% = .33 so 0.1% would be +/- .033 SPECS & PRICING Wow and flutter: Less than 0.02% Rumble: Greater than 80dB down Speed accuracy: Within .1% Dimensions: 20.5" x 15.5" x 10" Weight: 65 lbs. Price: $6000 I'd give it some more break-in time then contact VPI. I am sure they'll do right by you. And, yes, a minute difference in belt thickness will make a difference. Alberto

Just measured mine with the app: 33.6-7 on the highes (slowest) rung. That is still fast, right?

[Mr. Big]

Originally Posted by Maks

Does the RPM app support 78?

I believe it will. It's a free app so just download it and give it a try. I just gave it a spin on my table and it shows its speed is spot on for 33.3 and 45.

[jr_spyder]

Right. This app is not made specifically for turntables. It's to measure the rpm on anything you attach it to, like a kid, or a dog, or an amusement ride, or a turntable! So I was suspect it would be anything better then just fun, but it seems to be pretty accurate.

[Jean-Marc jmajma]

Not to tame your enthusiasm, here is what I posted on Clearaudio forum and it's with PlatterSpeed App.

If someone could explain if the Raw Frequency values are in the norm or not?



Hello,

I have a Champion Level II; I recently found on some slow piano tracks speed seemed a little bit low.

I've replaced the belt and I've oiled the axis.

I've bought a stroboscopic disc and the Dr Feickert's App for my Iphone with the disc playing a 3150 Hz.

I need help to understand the values I've found:

Mean Frequency: 3154.5 Hz

WOW according to DIN IEC 386
using method 2 sigma: +/- 0.30%
using method dynamic: +/- 0.19%

Raw Frequency:
max deviation (relative): -0.71%/+0.76%
max deviation (absolute): -22.4Hz/+23.9 Hz

Lowpass filtered Frequency:
max deviation (relative): -0.06%/+0.03%
max deviation (absolute): -1.8Hz/+0.8Hz
I made the test with an Audiotecnica which is a replica of the TECHNICS SL1210, with a direct motor drive quartz; here are the results;what do you think?



AUDIOTECNICA/CLEARAUDIO

MEAN FREQUENCY 3149,9Hz 3152.4Hz

WOW DIN IEC 386

METHOD 2 SIGMA +/-0.31% +/-0.32%

METHOD DYNAMIC +/-0.21% +/-0.27%

RAW FREQUENCY

MAX DEVIATION RELATIVE -0.52%/+0.74% -0.80%/+0.75%

MAX DEVIATION ABSOLUTE -16.3Hz/+23.4Hz -25.2Hz/+23.6Hz

LOWPASS FILTERED FREQUENCY

MAX DEVIATION RELATIVE -0.03%/+0.02% -0.05%/+0.03%

MAX DEVIATION ABSOLUTE -1.0Hz/+0.6Hz -1.4Hz/+1.1Hz

[Jean-Marc jmajma]

Here are Jérôme's turntables values:
Rega P9 Verdier

3163.9 Hz 3159.9Hz


Method 2 Sigma : +/- 0.22 % +/- 0.16%
Dynamic : +/- 0.19 % +/- 0.11%

Raw Freq :

Max Deviation relative : -0.5% /+0.7% -0.54% /+0.46%
absolute : -16Hz / +22.4Hz -17.1Hz / +14.6 Hz

Low Pass Filtered Freq :

Max Deviation Relative : -0.02 % / +0.05% -0.04 % / +0.05%
absolute: -0.8 Hz / +1.7 Hz -1.2Hz / +1.7Hz

[Good Times]

For me, the WOW figures are more important than the speed issues. Whether it's fast or slow to a small percent isn't a deal breaker for me. I can live with slightly different tempo/pitch so long as it's steady.

[Jean-Marc jmajma]

Exactly what I think, Good Times.

But what are the max Wow values human ear tolerate ?

[Good Times]

That's an interesting question. I wouldn't be surprised if it varies person to person.

After owning a very stable direct drive table, I was more picky when it came to belt drive tables.