Turntable speed question........ - diyAudio
Go Back   Home > Forums > Source & Line > Analogue Source
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Analogue Source Turntables, Tonearms, Cartridges, Phono Stages, Tuners, Tape Recorders, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 14th December 2013, 01:47 AM   #1
JoeDJ is offline JoeDJ  United States
diyAudio Member
JoeDJ's Avatar
Join Date: Mar 2011
Location: NY State
Default Turntable speed question........

I just checked my TT speed with a couple of of DL/printed strobe disks for 60hz.

There is absolutely no "wow".
However, it shows that both speeds are slightly slow by the same exact amount .....probably not enough to even notice.
This is with a new belt, clean pulley and platter... everything lubed and spinning freely.

So I checked my hz and discovered that it's 59.9 hz
My 66 year old brain is having a freeze....... Would that account for the slightly slow reading. or, would that make it appear faster?

Last edited by JoeDJ; 14th December 2013 at 01:55 AM.
  Reply With Quote
Old 14th December 2013, 03:01 AM   #2
DUG is offline DUG  Canada
diyAudio Member
Join Date: Jan 2003
Location: mississauga ontario canada
Is your motor a 60Hz induction type?

If it is then it will track your strobe and always appear slow...drive ratio issue.

If it is some other type of drive that is not derived from line frequency then it would show faster than 59.9Hz if actually accurate.

Either way it seems that it is actually slow.

Doug We are all learning...we can all help
"You can't stop the signal, Mal. Everything goes somewhere..."
  Reply With Quote
Old 14th December 2013, 03:19 AM   #3
diyAudio Member
Join Date: Mar 2007
Location: Canandaigua, NY USA
Your line frequency is probably far closer to 60 than 59.9; how good is your counter? Being belt drive, small errors in platter speed are likely. It's almost impossible to get the belt thickness just right for the pulley diameters so the platter speed comes out with no drift.
I may be barking up the wrong tree, but at least I'm barking!
  Reply With Quote
Old 14th December 2013, 04:25 AM   #4
diyAudio Member
Join Date: Dec 2012
Location: Buenos Aires
If you feel you can, stick very very evenly one or two scotch tape turns around the motor pulley, then reinstall the belt and check speed. If done correctly should not wow at all and hopefully the speed will be spot on.
  Reply With Quote
Old 14th December 2013, 06:22 AM   #5
JoeDJ is offline JoeDJ  United States
diyAudio Member
JoeDJ's Avatar
Join Date: Mar 2011
Location: NY State
I found the problem.

The belt guide to change speeds was hitting the belt ever so slightly in both 33 and 45.

Pulling the lever back slightly so the guide does not hit the belt brings the speed up to perfect. .

Tomorrow I will see what I have to do to adjust it to bring it down a hair. .
  Reply With Quote
Old 14th December 2013, 07:20 AM   #6
JoeDJ is offline JoeDJ  United States
diyAudio Member
JoeDJ's Avatar
Join Date: Mar 2011
Location: NY State
Actually, I think that the motor pulley just has to be brought up a hair .

Probably the the rubber on the motor suspension had shrunk just enough over the years to allow the motor and pulley assembly to drop down slightly.
Maybe there's an ajustment for that .
  Reply With Quote
Old 14th December 2013, 08:57 AM   #7
AndrewT is offline AndrewT  Scotland
diyAudio Member
Join Date: Jul 2004
Location: Scottish Borders
A strobe that operates at mains frequency will always track mains frequency.
The turntable will hopefully turn at the correct speed/frequency.
If this frequency is "locked" to the mains frequency, then the strobe will ALWAYS indicate the SAME speed error.

Only when the TT speed and/or the strobe speed are NOT locked to mains frequency will the strobe indicate changes in the relative speed of strobe to TT rotation.
regards Andrew T.
Sent from my desktop computer using a keyboard
  Reply With Quote
Old 14th December 2013, 05:41 PM   #8
JoeDJ is offline JoeDJ  United States
diyAudio Member
JoeDJ's Avatar
Join Date: Mar 2011
Location: NY State
As it turns out, the motor suspension was fine .
I had to raises the pulley a hair and bend the guide away from the belt a bit..
Speed is now fine.

I also played some piano and did not notice any flutter.

Last edited by JoeDJ; 14th December 2013 at 05:48 PM.
  Reply With Quote
Old 14th December 2013, 06:08 PM   #9
tinitus is offline tinitus  Europe
diyAudio Moderator R.I.P.
Join Date: Nov 2005
as I remember it, a tiny bit slower speed gives better timing, rythm, and 'sonics'

or ... maybe its really the opposite
just a tiny bit too fast, and all the good musical stuff is gone

and I believe that is a main problem with all modern music 'reproduction'
but with new and better digital technology this may be changing soon
sometimes we know very little, and sometimes we know too much
  Reply With Quote
Old 14th December 2013, 06:18 PM   #10
kevinkr is offline kevinkr  United States
diyAudio Moderator
kevinkr's Avatar
Join Date: Sep 2004
Location: Boston, Massachusetts
Blog Entries: 6
Best IMO to playback at the proper speed, obviously if the cutting lathe was running off speed all bets are off unless you have some range of adjustment and know by pitch whether you are on speed or not.

I don't buy that playing off speed is going to be an improvement, but small errors are probably undetectable in practice.

Back when I was restoring my MIT flea TD-124/I basket case I used it as a source for an audio get together, it was running several % slow and while I could tell, apparently I was the only one - the strobe and speed adjustment linkages were not fitted at that time and I had to adjust it manually with a vinyl engine strobe I printed out for the occasion.. The strobe confirmed it was running slow, and reaching under the table to adjust it was a royal pain. Lots of curious looks and comments from the well beered crowd.. lol
"To argue with a person who has renounced the use of reason is like administering medicine to the dead." - Thomas Paine
  Reply With Quote


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Calibrate speed on turntable wally5 Analogue Source 2 2nd July 2012 11:18 PM
Turntable speed billone Analogue Source 7 13th February 2012 06:20 AM
JVC turntable speed problem Fonic Analogue Source 1 7th June 2009 11:37 AM
Turntable speed under load YNWOAN Analogue Source 6 5th April 2008 11:01 AM
Turntable speed diyman Analogue Source 3 23rd May 2005 06:44 PM

New To Site? Need Help?

All times are GMT. The time now is 09:12 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2