On 06/07/2010 17:40, Jim Lesurf wrote:
In , Rob
wrote:
Why do belt drive turntables, usually British, have noisy motors? Is it
really beyond the wit of designers/manufacturers to use a quiet motor?

I've just bought a Roksan Xerxes, curiosity buy, and the motor vibrates
to the point that it can be felt through the plinth. Apparently (having
been through forums etc) this is quite normal. It's a testimony to the
design that very little of this finds its way to the platter or arm, but
why bother designing in such compromise, only to have to design it out?

Reverse the above to understand the reasoning. :-) A belt drive becomes
appopriate *because* a noisy (i.e. vibration prone) motor was chosen by the
maker. The combination of the belt and the turntable then act as a
mechanical filter.


Really!? What an utter shambles. Every motor vibrates - but they don't
have to physically shake the chassis they're mounted on.

Although and actually, I have done a quick search, and some of the
perhaps better motors are £50 upwards - so it is cost cutting with the
possibility of an 'upgrade' offered - £350 in one case.

Rob

In article , Rob
wrote:
On 06/07/2010 17:40, Jim Lesurf wrote:
In , Rob
wrote:
Why do belt drive turntables, usually British, have noisy motors? Is
it really beyond the wit of designers/manufacturers to use a quiet
motor?

I've just bought a Roksan Xerxes, curiosity buy, and the motor
vibrates to the point that it can be felt through the plinth.
Apparently (having been through forums etc) this is quite normal.
It's a testimony to the design that very little of this finds its way
to the platter or arm, but why bother designing in such compromise,
only to have to design it out?

Reverse the above to understand the reasoning. :-) A belt drive
becomes appopriate *because* a noisy (i.e. vibration prone) motor was
chosen by the maker. The combination of the belt and the turntable
then act as a mechanical filter.


Really!? What an utter shambles. Every motor vibrates - but they don't
have to physically shake the chassis they're mounted on.

Well, you may have a 'rogue' example in need of sorting out. Can't say as I
have no idea of what is normal for your turntable. But any vibration will
"shake the chassis" to some extent. Just a question of how noticable it is,
or if it is a problem.

Can you make a recording using a test disc and check for wow, flutter, and
rumble, etc? That way you can see if it matters. Or is it clearly audible
though the speakers with the volume at a normal setting?

Slainte,

Jim

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