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There are many different types of phono cartridge.
But all have a three things in common.
- Stylus Cantilever
- Stylus Suspension
- Stylus tip
During the technological hi fi boom 1974-1984, there were
specifications that helped define cartridge performance. Today, only a few
cartridge makers offer specs, most have stopped. The reason specs are
important, beyond the obviousness of product comparison, is that they hold the
maker to a specific quality, fit and finish. If a maker does not tell you the
profile of the diamond for example, then nothing stops that maker from using
different profiles as he sees fit. There is no guarantee that the cartridge you
buy is the same as the one you just read a review on. So if you really want to
be sure you are upgrading, demand specifications.
Now, what specs are
important.
- Stylus effective tip mass. This is the weight of the diamond
tip, cantilever and the active element on the other end be it iron, magnet, or
coil. The higher this figure, the poorer the hi frequency tracking ability.
0.4miligram should be the highest amount for a truly hi end cartridge. Hold a 1
pound weight in both hands with arms extended and try swinging it back and
forth quickly. Now you understand what the groove is doing to your stylus
assembly. At the height of the technological hi fi boom values as low as 0.17mG
were acheived and 0.3mG were common.
- Stylus Compliance. This is the springiness of the stylus
suspension. The compliance, along with the effective mass of the tonearm, will
determine the low frequency resonance of your arm/cartridge. Drop a stone on a
spring and it bounces up and down. That is what happens when the stylus
encounters a warp in the records surface. it bounces. You have probably seen
your speakers moving in and out to this rhythm. If the resonance is too low,
The stylus will hop right out of the groove, if it is too high, then deep bass
frequencies will be affected. With most tonearms today, compliances less than
15 should be avoided. Keep in mind that the lower the compliance the stiffer
the suspension; IE the more work the groove must do to wiggle that stylus back
and forth. It is a measure of both groovewear and resolution. At the height of
the technological hi fi boom, compliances of 20-30 were common. A note to
unipivot tonearm users. These arms, abandoned in the fifties because of their
lack of lateral stability, have made a comeback. Consult with the maker, for
the normal rules of compliance matching do not apply to these arms. you may
need a stiff suspension to avoid serious woofer pumping on warps.
- Stylus Profile. This is the shape of the diamond as it contacts
the groove. There are many different shapes and they are all borne of
historical evolution.
-The conical or spherical stylus is the simplest
and is common on inexpensive players. It is the least resolving since it cannot
trace the highest frequencies in the inner grooves. It will wear faster and
will cause damage to the highest frequencies in the inner grooves. This stylus
is incompatible with modern day high fidelity and the preservation of vinyl.
-The Elliptical stylus contacts the groove with a narrower footprint
and improves high frequency performance in the inner grooves. This shape was
developed to reduce inner groove distortion and extend the frequency
response.
-The Line contact stylus, borne out of the discrete
quadraphonic era, has a narrow and long footprint. It is the highest resolving
stylus design. And since it distributes the force along a line it exhibits less
groove wear and longer stylus life. If there is a downside, it is that with
worn records, this stylus will read more of the record wear. For your worn
records, you may want to have an elliptical or even a sphercal stylus for them.
Line contact styli go by various names: MicroRidge, Fritz-Geiger, Shibata,
Van-Den-Hul, etc.
- Tracking Force
-The lighter the tracking force, the less
groove wear. This would seem obvious but there are limits. Too light and small
amounts of dust will interfere with tracking and cause distortion. And that
distortion can cause groove damage. In my experience 1.5 grams is the best
overall tracking force comensurate with good fidelity and preservation of
vinyl. Modern vinyl should not be played at forces exceeding 2 grams to
maintain good preservation. Cartridges that track over 2 grams will prematurely
wear out your records.
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