Synopsis of Turntable Through Comparative Analysis of Stabilizers

Kazuhiro Nozaki, Meguro Jockey ClubTranslated by Yahya Chamkhi/NOMAN inc.

Introduction"Originally, the Technics turntable pitch controller used for changing keys in Karaoke wereused by African Americans to beatmatch and blend and were the origin of DJing." Theoverwhelming advocation for the Technics SL200 series turntable has made thisunsupported claim almost a reality. Before the quartz locked control SL1200 MK2, the pitchcontroller for the Servo control model, installed for correcting uneven rotation, together with
the Direct Drive mechanism,made it possible to mix sound sources without interruption. This redefined music, and fromhere on led to the birth of countless genres, which embody the spirit of the modern record.
However, it is also true that it was too “standard” and raised no doubts about the turntable'sperformance. I would like to expand our horizons and seek a perspective through thehistory of analog vinyls to provide a better playability for the so-called turntable, specificallyregarding the stabilizer.
Turntable Prehistory
The flat disc-type record, "Gramophone," was invented in 1887 by Emile Berliner, a former
Sound Engineer at Bell Laboratories. As a result, it became possible to duplicate a record
surface as a master recording, and mass production was implemented through the use of acompression molding. This eliminated the use of other vinyl formats, such as the wax
cylinder-type vinyl, "Graphophone," and became the foundation of the music industry. Fromthe 1912 SP vinyl to the 1948 LP vinyl. From DAT/MD subscription through to CDs,production has been continuing up to our present year. And to this day, after the electricmanufacturers established label divisions, invested in the music industry, and through thetwists and turns of digitization and analog re-assessment, the turntable is still manufactured
for playing vinyls. Before the actual analysis of the stabilizer, I would like to identify thestructure and the function of the turntable.

(Note: Bell Laboratories is the R&D division of AT&T, founded by Alexander Graham Bell; GE was founded byThomas Edison, inventor of the cylinder-type record. "Gramophone is used in British English, whereas"Phonograph" is used in America to refer to the same device. The former name of the U.S. Grammy Awards isthe Gramophone Award. The 12-inch LP was commercialized in 1948 by Columbia, the music division of CBS
Broadcasting, the 7-inch EP was commercialized in 1949 by RCA Victor accompanied with a victrola-machine,and Stereophonic was put into practical use in 1953. Broadcasters and electronics manufacturers haveinvested in the industrialization of music.

Structure and Function
The turntable for accurately transmitting the frequency information of sound waves
recorded on the record surface to the phono amplifier can be roughly divided into twoparts: the drive unit that firmly rotates the platter even at low speeds, and the arm unit thattraces the recorded groove length and frequencies, and sends them to the phono amplifier.
To suppress uneven rotation rate (Wow and Flutter) and implement accurate sound tracing
while operating stably, the focus is on controlling the vibration of the drive unit. There aredifferent drive methods, such as Idler Drive, Belt Drive, and Direct Drive. In other words,
each has a different operating mechanism and vibration control design.
In typical models, the Garrard 301 is an Idler Drive that controls the spindle torque rotationfrom the inner side of the platter via the idler (rubber roller). A Belt Drive, the most common
method, controls the platter rotation through belt torque, whereas the Thorens TD-521 is a
floating system in which the frame housing is independent of the torque and plattercomponents. The Nottingham Analogue Studios’ Spacedeck uses a synchronized motor
belt drive that is set in motion by manually turning the platter for amplitude control withminimal torque (To change the RPMs the belt position must be moved by hand). The directdrive developed by Technics, which both generates magnetic force by passing an electric
current through an electromagnet and controls platter rotation at the end/start of crystal
oscillation has been adopted since the SL1200 MK2 and has become an industry standard
for accurate functionality and high durability (The durability is so high that production was
once actually paused due to the surging second-hand market). For direct-drive units
without a mechanism for deceleration or transmission that create high torque at low
speeds, there are Micro Seiki DDX-1000 and Technics SP-10, which have separate plattersand arms.
These turntables all play the same sound wave signal engraved on the record surface
through a phono amplifier, but it is also true that the sound output differs from turntable toturntable depending on each drive mechanism and vibration control design, as with thephono amplifier that equalizes the sound source inversed during cutting with the RIAA
curve. The lightest 7-inch (45 g) vinyls are more sensitive to the mechanical amplitude ofturntable torque compared to 12-inch (140g) and 12-inch heavy records (180g); the line
speed is delayed and the sound pressure is lower, so it is expected that the damping effectcan be visualized by comparing the presence or absence of stabilizers.
Note) Since the surface area of a record is limited, the information of the sound wave vibration stored in thegrooves is processed into a curve defined by the RIAA (Recording Industry Association of America) andrecorded. Since the groove (pitch) becomes wider as the lower range is recorded, and the groove (depth)
becomes deeper as the volume is recorded, based on the RIAA curve established in 1953 by the RIAA, thelower range is decreased and the higher range is increased.

The Role of the Stabilizer
One of the plans of the stabilizer OTM80821 (Oitomi 7”/12” Dual Disc Stabilizer) is for thehigh resolution sound quality implemented by the vibration control and low amplitude
torque by the housing of the idler drive and the belt drive to be applied to direct drivemachines with the most reliable functionality and sturdiness. For that purpose, since its
weight is the lightest and the drive unit is highly sensitive to mechanical amplitude, this 7”/
12” dual stabilizer (540g) with an adapter function that fits into the center hole of a 7-inchrecord (45g) with low sound pressure due to slow linear velocity is used. The presence orabsence of the stabilizer was measured under the same recording conditions by the same
artist based on chronologically-released sound sources: a sound source with clearlyrecorded low frequencies (SAM65B1), a sound source with no recorded low frequencies(7K308A1), and a sound source with clearly recorded mid-low frequencies (FLA6A1).
Note) Small special vinyls such as 5-inch vinyls are not included due to not being commonly used.

Ripping Specifications
In the graphs, the Y-axis is decibels (db) and the X-axis is the frequency (Hz) band (thehighest peaks are closest to 0 dB, the lowest frequency bands are to the left), the waveformpeak values measured by the spectrum analyzer are mapped, and the presence orabsence of the stabilizer is layered.
The recording was done through a line input of the sound source played on the Technics
SL1200MK2 / Ortofon NC-S (OM) through an XLR via the United Recording Electronics
Industries Model1622 phono amplifier at CH + 7 / MAS + 7dB, to 32bit Float / 96kHz. The
sound source was released in chronological order by the same artist, and the recording
equipment/procedure and setting was assumed to have changed as little as possible, allusing a 7-inch, 45RPM EPs and played with an official adapter and stabilizer.
SAM65B1(JAN'88 release sound source with clearly recorded low frequencies), 7K308A1(SEP’88 release sound source with no recorded low frequencies), FLA6A1(JUL'89 releasesound source with clearly recorded mid-low range).
Note) Technics SL1200 MK2 is the earliest model of direct drive with rotation control by quartz locked and has
been subsequently improved with MK3 / 3D, MK4, MK5 / 5G, MK6, 1200G / GR, MK7, not only in terms offunction but also in the mechanism. In terms of aspects, each model is designed to reduce the platter weightand increase the torque. Additionally, since the sound source focuses on frequency range (Hz) and decibels(db) as material for comparative weighing, the Artist / Title in the body text is omitted.
(SAM65) Yosui Inoue- “Negative” (SAM65B1) Lyrics and Composition -Yosui Inoue / Arrangement -Yuji
Kawashima (For Life Records)(7K308) Yosui Inoue- “Konya, Watashi Ni” (7K308A1) Lyrics and Composition -Yosui Inoue / Arrangement -Yuji
Kawashima (For Life Records)(FLA6) Yosui Inoue- “Yumenemi” (FLA6A1) Lyrics and Composition -Yosui Inoue / Arrangement -Yuji
Kawashima (For Life Records)

Comparative Analysis
On the whole, when vibration is suppressed by the stabilizer, the effects of increasing thelower range, decreasing the higher range, and suppressing the mid-range can be read.
Although the frequency range (Hz) changes depending on the musical composition andthe instruments/equipment used, starting from 10Hz (which is outside the audible range),
the low range is raised, and coming from above 22kHz (also outside the audible range), thehigh range is threshed, so the center balance of the dynamic range is pushed downward.
This matches the audible impression that the bass drum is increased and the sound image

appears to “sit down.” Although the recording environment artificially eliminates noise
components, the 7-inch makes a unique rattling sound when the adapter is fitted, butchanges to a deep sound like a 45 RPM 12-inch when the stabilizer is mounted. While
showing the possibility that the so-called peculiar loudness produced by the 7-inch is theresult of the mechanical amplitude of the direct-drive torque combined with the lightness ofthe 7-inch’s weight, comparison with a heavier lacquer record with the same linear velocity,which is obtained by applying acetate to a copper record, along with multi-faceted analysis
is required to determine the difference between the sound source used by the adapter andthe stabilizer.
Note) The principle of the noise canceling function is that the phases cancel each other out and the localization
is canceled when the sound source of the negative phase is mixed with the sound source of the in-phase, andthe difference is also extracted by this.

Comparison of EffectivenessThe stabilizer, which has been typically used to suppress external vibration and impact inturntable playback, is effective not only for the 12-inch but also for the 7-inch playback,which is highly sensitive to the mechanical amplitude of direct drive. This effectiveness isthe result of the substitution of CDs and subscriptions for the main purpose of the media
called the 7-inch EP, developed for promotional use of the jukebox autochanger and RCA
Victor's 45 RPM Victrola player, a product now mainly suited for the turntable era. Good
results can be expected when digitally sampling/quantizing analog sound sources which
are often nowadays ripped on desktops and played on mobile devices.
Also, in considering its effectiveness, I hope that the structural understanding of analog
turntables will contribute to the further development of the music industry. I would like to
use the modern collective intelligence in which information is updated and corrected online
to make a comparison between a wide variety of 7-inch vinyls such as 33 RPM compact 33
s 7" ep, which have increased the number of recorded songs at the expense of linear
speed, Styrene /injection-molded records, which differ in material and shape depending on
the record manufacturing factory, and flexi, along with 12-inch heavy records, Dynaflex
records from the oil crisis period, Quadrophonic records, etc., and utilize it as feedback
when creating the next lot and body of work.

Music is the culmination of sound wave vibrations that resonate on multiple layers, and it isimpossible to perceive the sonority of chords and tones outside of oneself. However,because music cannot be objectively visualized, I believe that it is something that can beshared beyond language, nationality, generation, and gender. It is my great desire that theeffectiveness of this 7”/12” dual disc stabilizer OTM80821 becomes widely accepted andbrings about new perspectives toward record playback.
Note) The drum break of The Winstons- “Amen Brother” 7”, released by Columbia in 1969, has been sampled
on almost every jungle track but depending on the manufacturing plants of the West Coast, Mid West, and East
Coast, records made of vinyl and Styrene exist with the same catalog number. This is due to the difference inthe record molding methods of the time, as injection molding was being attempted to replace compression
molding and each method had its own line. Vinyl was used for the California record, and Polystyrene was used
for the Illinois and New Jersey records. In addition, the 7-inch records of Nippon Columbia during the 1970s
also used a mixture of compression-molded EP and injection molded records with the same catalog number.
Injection molding is an idea that preceded the method of molding with a 3D printer but is inferior in durability
because vinyl cannot be used during the injection process.

References"Hitmen”- by Fredric Dannen, translated by Toshiko Yoshida, published by Kadokawa Shoten"History of Playback Media"- by Fumikazu Taniguchi, Record Collectors May 2005 Special Edition, published byMusic Magazine"Systematic Report of Analog Disc Record Technology and Status of Existing Materials"- by Takeaki Anazawa,
National Museum of Nature and Science Industrial Technology History Materials Information Center
http://sts.kahaku.go.jp/diversity/document/system/pdf/083.pdf
https://en.wikipedia.org/wiki/Phonograph_record
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https://en.wikipedia.org/wiki/Single_(music)#7-inch_format
https://ja.wikipedia.org/wiki/%E3%83%AC%E3%82%B3%E3%83%BC%E3%83%89#7%E3%82%A4%E3%83%B3%E3%83%81%E3%82%
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https://blog.discogs.com/en/a-short-guide-to-the-different-mixes-of-the-amen-break-2/r"Elevator Music in Japan"- by Yuji Tanaka, published by DU Books