The Usual Rega too fast problem

[STD305M]

Hi Richard,
I also have this app and it shows my strathclyde turntable as running at 34.3, also my project 2xperience which is only 2 months old running at 34.3.
I think you can safely say the app is not very accurate.

Regards Steve...

[STD305M]

Default
Hi Richard,
I also have this app and it shows my strathclyde turntable as running at 34.3, also my project 2xperience which is only 2 months old running at 34.3.
I think you can safely say the app is not very accurate.

Regards Steve...

[walpurgis]

With consistent speed excess, the obvious answer is to turn the motor pulley groove diameter down a touch. But most folk don't have a lathe.

[STD305M]

Duplicate

[bbbiker800]

Once again thanks for your help guys, much appreciated.

This exercise has made me wonder whether there's a lot of people - who don't have a mega buck belt drive - who don't really know what their deck is running at. That said they are probably happy and have no suspicions unlike paranoid me!!

TBH I wasn't expecting the mobile application to be totally accurate but was thinking that if I got down to say 33.5 then that would be about right and would also take into account the .1 which many attribute (forums!) to stylus drag.

Rather than visit my rega dealer then, I'll find a way to strobe it and see what I get.

[Sand Dancin Donkey Walker]

If my memory serves me right, the National Grid have an obligation to supply the mains frequency at 50Hz +/- 1%.
So in theory 49.5 to 50.5 Hz with the exception of fault disturbances, usually only short duration. On a couple of sites I have worked we set up a monitoring system.
The results showed only once in 48Hrs did the mains frequency drop[ under 49.5Hz but strangely it sat slightly above the standard at 50.1 to 50.2Hz
That would only represent my local area, not sure how other areas may change? Though the Grid is a powerful system and should keep tight control of the frequency.

There are plenty of down loadable strobe discs, just light them up with a filament lamp and you should show what the actual speed is, within the mains tolerance.

[walpurgis]

There are plenty of down loadable strobe discs, just light them up with a filament lamp and you should show what the actual speed is, within the mains tolerance.

Surely, if the mains frequency is off, the strobe disc readings will be inaccurate?

[Stratmangler]

Surely, if the mains frequency is off, the strobe disc readings will be inaccurate?

He did say "within the mains tolerance".
I've been thinking about it, and if the mains is off it will still be possible to see if the platter rotates at the correct speed, because the lamp will also be affected.

So no, Geoff, if the mains frequency is off, the strobe disc readings will not be inaccurate.

[RothwellAudio]

First off, you need to know if the turntable is running fast/slow or not - I have no faith in that app to give you an accurate measurement. There is a very easy way to check if you have the same music on CD and vinyl. Just play both both at the same time (they don't have to be accurately synced) and flick between the two. Any pitch/tempo difference will be obvious, and I mean really obvious.
If there is an error, what can you do? Well, you certainly can't change the speed by altering the mains frequency with a lightbulb because the speed is locked to the frequency of the mains, not its voltage. BTW, the mains frequency is held to a very tight tolerance so that shouldn't be problem. Really, you're left with playing about with different belts to fine tune the speed unless you go down the route of expensive speed controllers.
But first, check the problem with a CD/vinyl comparison.

[rubber duck]

So no, Geoff, if the mains frequency is off, the strobe disc readings will not be inaccurate.

You'll probably be much better off looking at a strobe provided you're using a battery operated strobe light, or are certain your mains frequency is 50Hz.

I use a mains regenerator locked on 50Hz.