[Dick Pierce[_2_]]

Audio Empire wrote:
On Mon, 26 Sep 2011 07:06:39 -0700, Dick Pierce wrote
All other things being equal, a straight tone arm
will have lower mass and higher mechanical stability
than a curved tone arm, and lower mass can be argued
as being a good thing.

Except when low-mass arms are combined with low compliance cartridges, and
make no mistake, there are plenty of high-end cartridges which are low
compliance.

Except that it's a trivial excercise to increase the mass of
a low-mass arm to something suitable.

Even for those that might claim
that for a given cartridge, a higher moving mass is
required, that is trivially achieved by adding mass to
the mounting of the cartridge. It's MUCH more difficult
(read: it's pretty much impossible) to remove mass from
an arm whose mass is too high for a given cartridge.

That's why matching arm to cartridge is so important. The best way I know to
render a large portion of a real-world record collection unplayable is to
afix a fairly low mass arm with a really high-compliance cartridge. The best
way I know to make one's records sound bass-heavy and muddy is to couple a
low mass tone arm with low compliance cartridge. And the result is FAR from
trivial in either case.

I did not say it's a trivial case. I said that if a higher
mass is required, which is the same as saying if the
effective arm mass is too low, the proper mass trivially
achieved by adding mass.

The same is NOT the case for an arm whose mass is already
too high: there is no real-world solution for reducing the
effective mass of an arm.

* Any profile other than a straight line MUST have more
moving mass, all other things being equal.

Also correct. But to say that low-mass in a tone arm is always desireable is
overly simplistic and not correct. The arm and cartridge must work together
as a synergistic system. Record players are mechanical systems and mechanical
systems have a number of criteria to meet before they can be considered a
successful solution.

Are we not getting it? If the mass of an arm is too low,
then ADD MASS TO IT. Why does this seem such a difficult
concept? A low-mass arm uis a far more suitable solution
for a much wider range of cartridge compliances than a high
mass arm. A low mass arm can work very well as-is for high-
compliance cartridges, can work very well for moderate-
compliance cartidges with the addition of a little extra mass,
and can work very well for low-compliance cartridges with
the addition of suitably greater amount of mass.

Thus it CAN be argued that a low-mass arm is suitable for
a wider range of cartridges than a high-mass arm simply
through the expedient of adjusting the mass accordingly.

The same is absolutely NOT true of high-mass arms.

Do you not agree, and if not, why not?

Tone arm shape IS important, but the reasons often given
are irreleventa or just plain wrong.

Mostly they're irrelevant as there are, in engineering,
usually more than one path to a satisfactory solution.

And as is often the case in high-end audio, for ever
path to a satisfactory solution, there are many more
paths to unsatisfactory solutions that are highly
revered.


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+ Dick Pierce |
+ Professional Audio Development |
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