Specification

54 - audio-technica phono cartridges guide - 2019/20
Cartridge-making dictionary Audio-Technica’s guide to cartridge-making terminology
33rpm
33rpm very often denotes 12” LP Vinyl records (1949‑
Today), that should be played at a speed of 331/3rpm.
Rpm stands for Rotation Per Minute.
45 rpm
45rpm very often denotes 7” Vinyl records (1949‑Today),
that should be played at a speed of 45rpm. Rpm stands
for Rotation Per Minute.
78rpm
78rpm very often denotes 10” Shellac SP Gramophone
records (1925‑1950), that should be played at a speed of
78rpm. Rpm stands for Rotation Per Minute.
Anti-skating
When the record is in play, the friction between the
stylus in the groove of the record and the length of the
arm (the distance between the tip and the arm bearing)
creates a force that pushes the cartridge toward the
center of the disk. Anti‑skating creates a force that
pulls the arm towards the outer edge of the disc to
compensate it. Because records don’t have a constant
amplitude, a static compensation will never totally cure
the problem. It is a matter of balance. Badly set anti‑
skating will produce channel balance and distortion
issues. When the anti‑skating is set too high, the left
channel will distort during loud passages, while on the
other side if it’s too low, the right channel will distort.
Also the amount of anti‑skating depends on the shape of
the tip. Conical stylus tends to require more anti‑skating
(due to the amount of friction generated by their shape)
than more complex shapes (Line Contact or Micro linear).
Azimuth (see also Tilt)
For magnetic tape drives, azimuth refers to the angle
between the tape head and magnetic tape. For phono
cartridges, Azimuth is the angle between the surface of
the record and the vertical axis of the cartridge.
Note the dierence between cartridge removable head
shells: some models such as the “Technihard Series”
(page 50) feature an “azimuth” adjustment. This feature
is particularly useful when it is not provided by the
tonearm itself.
Bonded diamond
Bonded diamond refers to a stylus where
the diamond tip is glued on a metal shank
that is itself glued into the hole of the
cantilever. This construction may increase
the mass of the overall tip and aect
transient reproduction compared with nude styli that
are preferred and used on higher‑priced models.
Boron (boron cantilever)
Boron is a chemical element from the metalloid family,
extracted from Borax and Kernite. Its atomic number
is 5. Boron is used for high‑end cantilevers due to its
lightweight and high‑rigidity properties. It reaches a
score of 9.5 on the Mohs hardness scale (for reference
Diamond scores 10 and Aluminium 3).
Cantilever (stylus cantilever)
Cantilever
Styli are principally made of three components: Stylus
Tip, Stylus Cantilever, and Stylus Suspension.
The cantilever is a tiny suspended “arm” (solid or pipe)
that holds the Diamond Tip on one end and transfers the
vibrations to the other end where the Magnets (in case
of MM cartridges) or the Coils (in case of MC cartridges)
are housed.
Dierent materials are used to make a cantilever:
Aluminium, Saphyr, Beryllium, Boron... The lighter and
stier being the best.
Cartridge (Phono Magnetic Cartridge)
The phono cartridge is the transducer used for the
playback of gramophone records.
The phono cartridge converts the mechanical energy
(vibrations) from a stylus riding in a record groove into
an electrical signal that will be amplified then processed,
recorded, or played through a sound system.
Channel Balance
The channel balance of a cartridge is the ability of the
transducer to reproduce left and right channels in the
same manner. Channel balance should be part of the
cartridge specifications, it expresses the possible output
dierence in dB from one channel to another. A cartridge
with ideal channel balance will playback any mono
signal with equal level in both channels. The channel
balance will be 0dB. The ratio of the signals between
the two channels is specified in dB. Channel imbalance
can result in several factors independent from the
cartridge itself: mechanical factors include incorrect
azimuth settings, misalignment of the tonearm and/
or of the cartridge on the headshell, and/or improper
anti‑skating adjustment. Other Channel imbalance
issues, independent from the cartridge or the turntable,
could include mismatched cables, electronic elements
such as stereo preamplifiers, speaker system, speaker
positioning and/or room acoustics.
Channel Separation
The channel separation of a cartridge is the ability of the
transducer to deliver only signal on the left channel of
the cartridge, and nothing on the right channel when
there is only signal on the left channel groove,and vice
versa. Channel separation is frequency dependent.
Audio‑Technica indicate in the specifications the Channel
separation, specified at 1kHz. For high‑end cartridges,
Audio‑Technica provides channel separation curves,
showing the separation in dB from 20Hz to 20,000Hz.
A high channel separation provides a better stereo image.
Compliance
Compliance is the inverse of stiness. Every cartridge
works as a suspension, a high compliance cartridge will
be suited for a low mass tonearm and a low compliance
(stier) cartridge will be suited for a high mass tonearm.
There is not a perfect compliance number, the cartridge
compliance together with the eective mass of
the tonearm/cartridge combination determine the
tonearm’s fundamental resonance. For optimal results
the frequency should be maintained between 9‑13Hz.
Connecting (the phono cartridge)
To install a Phono cartridge, connect the four wires of
the cartridge headshell to the correct terminals on the
back of the cartridge.
The four wires are colour‑coded and generally labeled
as follows :
Left Channel: White
Left Channel Ground: Blue
Right Channel: Red
Right Channel Ground: Green
Conical
(form factor of the diamond stylus)
Also called spherical, because of the shape
of the tip of the cone. Conical shaped stylus
are simple to produce, therefore it becomes
the most popular when economy is a factor.
Counterweight
(Tonearm Counterweight)
Arm rest
Arm rest
Headshell
Tonearm
base
Tracking force
fine adjustment
weight
Tonearm
counter weight
Anti-skating
device
Quad lead
wires
Dual Moving Magnet cartridge
Audio‑Technica’s Vertical Dual Magnet phono cartridge,
unlike conventional cartridges, use the 90° V‑Shape
of the cutter head. The standard cutter head (used
to record the vinyl master) uses two transducer coils,
mounted perpendicular to each other at 45° from
horizontal, to cut the channel: one in each wall of the 90°
record groove. This way, the cartridge achieves accurate
tracking, excellent channel separation, high definition of
the stereo image and extreme clarity over the entire
audio spectrum.
Elliptical
(form factor of the diamond stylus)
An Elliptical stylus is produced starting from
a Conical Stylus, then two cuts are made in
order to make the vertical contact longer
and the front to back contact narrower.
The elliptical tip follows the groove modulation with
more precision than a conical tip, improving frequency
response, phase response, and lowering distortion,
specifically in the inner turns of the record.
Frequency Response
Frequency response is the quantitative measure of the
output spectrum of the cartridge in response to the
stimulus of the record groove modulation.
It is a measure of the magnitude for the output as a
function of frequency; typically measured in decibels
(dB). In the case of cartridge measurement, the input
signal will be a constant‑amplitude pure tone through
the bandwidth provided by a reference record.
Impedance
The impedance is a measure of the total opposition that a
circuit presents to alternate electric current. The output
impedance of an electronic device is the impedance of
its internal circuit “seen” by any device connected to its
output. The Input impedance of an electronic device is
the impedance “seen” by any source connected at its
input.
Input impedance of the phono preamplifier and output
impedance of the cartridge should be properly matched
to achieve optimal sound. An impedance mismatch will
work as a filter and degrade the sound making it dull or
harsh depending on the setup. A general rule of thumb