'Number9' TT AC motor controller web site finally up

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YNWaN
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Re: 'Number9' TT AC motor controller web site finally up

Post by YNWaN » Wed May 30, 2018 8:48 pm

I’m sorry Andy, all I know about this unit is what I have read - to be honest, this seems to be the hobby/retirement(?) project of an ex audio dealer so perhaps he’s on holiday or been unwell. I’m not making excuses as I have no idea - but I get the impression you are dealing with a one man band company (with all the pluses and negatives that entails).
Mark

ChrisOH1
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Re: 'Number9' TT AC motor controller web site finally up

Post by ChrisOH1 » Tue Jun 11, 2019 2:53 pm

Did anything come of this? I've emailed to ask for information but wondered whether anyone has any experience now. I have two motors in my deck and this would seem like an ideal way to improve it.

YNWaN
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Re: 'Number9' TT AC motor controller web site finally up

Post by YNWaN » Tue Jun 11, 2019 7:16 pm

I’ve been wondering too. It’s actually a very sophisticated bit of kit and it’s possible the technology has been bought by another party wanting to use it for their own (commercial) turntable design - but, who knows.

However, I’m not personally a fan of multiple motor solutions and believe they only offer a benefit because of their inherent disadvantages - sort of two wrongs making a semi right :().
Mark

ChrisOH1
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Re: 'Number9' TT AC motor controller web site finally up

Post by ChrisOH1 » Wed Jun 12, 2019 1:34 pm

Shame if it has gone, i'd love to add this to the list.

I got the deck from Les to replace a modified LP12, which it did very well IMHO. The two motor concept, one at 12, the other at 6 o'clock seems to have some logic in terms of evening up the pull the belt exherts. Not sure what the downsides are to be honest

sq225917
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Re: 'Number9' TT AC motor controller web site finally up

Post by sq225917 » Wed Jun 12, 2019 2:22 pm

Double the RMS vibration amplitude, twice the number of vibration generation sites and therefore different frequency/amplitude interactions with various parts of the deck. An increase in radiated electrical noise from the motors and a guarantee that one motor comes very close to the cartridge. Twice the acoustic noise and twice the pulley/radius belt stretch and creep to recover from every revolution.

On the upside you have more motor torque to work against stylus drag.
One more Paradise left to complete.

ChrisOH1
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Re: 'Number9' TT AC motor controller web site finally up

Post by ChrisOH1 » Wed Jun 12, 2019 3:50 pm

I guess i could have figured some of that out. Glad there's an upside :D The deck needs some work as there is some hum introduced as the cartridge traverses the deck. I have two of the decks and one suffers this, the other not and given both have the same motors located in the same place its a bit of a puzzle

REXTON
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Re: 'Number9' TT AC motor controller web site finally up

Post by REXTON » Wed Jun 12, 2019 5:07 pm

I had a lucky escape with this one!

YNWaN
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Re: 'Number9' TT AC motor controller web site finally up

Post by YNWaN » Wed Jun 12, 2019 5:47 pm

Does one deck have a Grado cartridge on Chris? These are notorious for picking up the radiated magnetic field from motors.
Mark

andyr
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Re: 'Number9' TT AC motor controller web site finally up

Post by andyr » Thu Jun 13, 2019 12:19 am

ChrisOH1 wrote:
Wed Jun 12, 2019 1:34 pm
Shame if it has gone, i'd love to add this to the list.

I got the deck from Les to replace a modified LP12, which it did very well IMHO. The two motor concept, one at 12, the other at 6 o'clock seems to have some logic in terms of evening up the pull the belt exherts. Not sure what the downsides are to be honest
As someone who has been using a Number9 for a couple of years - and who moved from 1 motor to 2 - there are no downsides that I can hear. :)
sq225917 wrote:
Wed Jun 12, 2019 2:22 pm
Double the RMS vibration amplitude, twice the number of vibration generation sites and therefore different frequency/amplitude interactions with various parts of the deck. An increase in radiated electrical noise from the motors and a guarantee that one motor comes very close to the cartridge. Twice the acoustic noise and twice the pulley/radius belt stretch and creep to recover from every revolution.

On the upside you have more motor torque to work against stylus drag.
As the motors are bolted to the underside of metal plates - which are earthed, Simon - I don't hear any electrical noise (through the speakers) from the LOMC which is near the 6 o'clock motor. And certainly none from the 12 o'clock motor.

There is also no motor noise ... but, certainly, there is twice the amount of pulley/radius belt stretch and creep, with 2 motors. Sonic benefits outweigh this negative, though - IME.

Andy

sq225917
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Re: 'Number9' TT AC motor controller web site finally up

Post by sq225917 » Thu Jun 13, 2019 9:19 am

Andy, My comments were with reference to Chris's deck (les's design and motor choice). Though I'd bet if you actually measured your deck properly you'd find the same at some level.
One more Paradise left to complete.

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