MANUFACTURER'S SPECIFICATIONS
Frequency Response: 5 Hz to 40 kHz ±1.5 dB. Output Voltage: 0.2 mV. Channel Balance: ±0.5 dB. Channel Separation: Better than 27 dB. Impedance: 3.5 ohms. Compliance: 18x10^6 cm/dyne. Tracking Angle: 20 degrees. Stylus Force: 1 to 1.5 grams. Stylus: 0.3 x 0.8 mil elliptical diamond. Weight: 10 grams. Price: $125.00.
Although the principle of the moving-coil cartridge has been known for a long time, about the only cartridge of this type marketed in recent times is the Ortofon. Another such pickup that has recently become quite popular with audio enthusiasts is the Supex SD-900/E. This cartridge is manufactured in Japan and distributed in this country by Sumiko, Inc.
Like all moving-coil cartridges, the SD-900/E's output voltage is very low. Most moving-coil cartridges rarely exceed an output voltage of about 70 microvolts, thus making them prone to hum and noise problems. The Supex SD-900/E has an output voltage about three times greater than previous moving-coil cartridges, 200 microvolts. This increased output voltage reduces the possibility of hum and noise problems. However, an output voltage in microvolts requires the use of either a special cartridge transformer or preamplifier ("head amp"). Our experience indicates that the Supex SD 900/E should be used with a cartridge preamplifier, such as the Mark Levinson JC-1, the output of which is fed to the usual phono cartridge input of an audio system. The JC-1 is an inverting cartridge preamplifier, requiring that the plus and minus leads of the Supex be reversed at the cartridge on each side, i.e., the hot and ground leads be reversed on the left side and similarly on the right side.
The manufacturer recommends this cartridge for CD-4 use despite the fact that the stylus is a nude biradial diamond (0.3 x 0.8 mil). Interestingly, the Supex SD-900/E scored very high on all the strict parameters used in testing stereo and discrete (CD-4 and UD-4) cartridges with an optimum tracking force of 1.5 grams and 2 grams for anti-skating. However, because of the lack of a Shibata or Shibata-like stylus, which engages a greater area of the record groove wall, we cannot unreservedly recommend it for general use in discrete CD-4 or UD-4 quadraphonic playback, because of the possibility of wiping the carrier off the groove wall.
The Supex SD-900/E is, however, one of the finest stereo cartridges we have ever tested. Sonic clarity is superb with good definition, particularly in the bass. Transient response and applause definition is excellent.
Measurements
As is our practice, measurements were made on both channels, but only the left is reported. During the test period, the temperature was 70° F ± 1° and the relative humidity 52% ± 2%. The following adjustment and test records were used in making the measurements: JVC 4DE-205; WEA PR186; Shure TTR-107, TTR-103, TTR-110; Columbia STR100, STR-111; JVC TRS-1004, TRS-1005; Stereo Review SR-12; B & K QR-2009; Deutsches Hi-Fi No. 2; Panasonic SPR-111; Denon ST-5003 (UD-4); Ovation OVQS/4000 (QS); Columbia SQT-1100 (SQ), and AEL 100,101. Both the square wave test (photograph) and the 4:1 intermodulation distortion tests reported in this cartridge profile were made using the new CBS Laboratories Professional Test Record STR 112, which was released in May 1975 and replaces the now obsolete STR 111. The STR 112 is one of a series of nine updated professional test records recently released by CBS Laboratories. These should prove invaluable in testing the various parameters of audio systems.
Frequency response was flat within ±2 dB from 20 Hz to 10 kHz, + 3 dB at 13 kHz, + 2 dB at 20 kHz, + 1 dB at 30 kHz, 0 dB at 40 kHz and-4 dB at about 48 kHz. Separation is better than 27 dB to 8 kHz and then diminishes to 23 dB at 10 kHz, 15 dB at 20 kHz, 13 dB at 30 kHz, 4 dB at 40 kHz, and O dB at about 43 kHz. Channel balance was remarkable, being within 0.3 dB, and trackability is good. A good CD-4 cartridge should produce more than 0.7 mv at 30 kHz from the JVC1004 test record, where the 30 kHz monophonic signal is recorded at the 5.5-in. diameter of the test record with a peak velocity amplitude of 5 cm/sec. The Supex output voltage at 30 kHz was 1.5 mv. On a test record designed by this reviewer (AEL-100), which contains tracking velocities from 7 cm/sec to 70 cm/sec at 1 kHz, lateral cut, peak velocity, the Supex tracked 30 cm/sec with no difficulty. Signal output without the JC-1 Levinson cartridge preamplifier was 53 µv/1-cm/sec and with the JC-1, it was 1.2 my/1-cm/sec.
Wt. 9.53 g.; d.c. res., 3.2 ohms; Inductance, 91 uH; Opt. tracking force, 1.5 g.; Anti-skating, 2 g.; Output, 53 µV/1cm/sec. without the IC-1 cartridge preamp and 1.2 mV/1cm/sec with the JC-1; IM dist. (4:1) +9 dB lat., 200/4000: 5.6%, + 6 dB vert., 200/4000: 3.0%; Crosstalk,-27 dB; Ch. Bal., 0.3 dB; Trackability: High Freq. (10.8 pulsed) 30 cm/sec.; Mid-Freq. (1000 + 1500 Hz lat. cut) 25 cm/sec; Low Freq. (400 + 4000 Hz lat. cut) 19 cm/sec; 30 kHz mono signal 1.5 mV. Passed all bands of the Shure Audio Obstacle Course Era III test record except for the 5th level of the violin where it just starts to mistrack. Cartridge-arm resonance was less than 10 Hz.
Fig. 1--Frequency response and separation of the Supex SD 900/E using JVC's
TRS-1005 test record.
Fig. 2--1-kHz square-wave response of the Supex SD-900/E using CBS Lab's
STR-112 test record.
Listening Tests
The Supex SD-900/E cartridge was used with the following demodulators in the listening evaluation: Technics SH-400, Panasonic SE-405, JVC 4DD-5, and Harman/Kardon +44.
Separation and 30-kHz carrier signal adjustments (where required) were easily accomplished, though with the Technics SH-400 demodulator, a little extra care was necessary to make certain that the cartridge was properly "locked-in." The Denon (Nippon Columbia) UDA-100 (UD-4) demodulator was also tried, and separation was accomplished in both the UD-4 and CD-4 positions without difficulty. The SQ and QS decoders used were the Lafayette SQ-W and Sansui X-2, respectively, as well as the SQ and QS positions on the Denon UDA-100. The speakers used in this evaluation were the efficient Cerwin-Vega 211-Rs in the front and the R-26s in the rear.
Additional speakers used were four relatively less efficient Micro-Acoustics FRM-1s, and most of the listening evaluation was performed with them. A new, very efficient sub woofer from Janis Audio Associates, 2889 Roebling Ave., Bronx, N.Y. 10461, was used in combination with the Crown VFX-2 crossover network and the Model 207-A Tiger .01 amp from Southwest Technical Products to drive the subwoofer below 100 Hz. Since bass frequencies below 100 Hz are essentially non-directional, only one subwoofer was used in a common mode configuration, which required a summing network added to the Crown VFX-2 crossover network for the speakers serving the stereo or the front quadraphonic pair. Two Phase Linear 4000 preamplifiers and a pair of Crown D-150 amplifiers drove the main speakers. The turntable was the Technics SP-10 with the Audio-technica AT 1009 tonearm installed on the turntable base.
A rigorous listening evaluation of the Supex SD-900/E was made in both the stereo and quadraphonic modes, using all the CD-4 records listed in our report published in Audio, March, 1974, p. 39, plus the following additional new records, which demonstrate the capabilities of this cartridge.
Stereo
Organ Music from Westminster-ARK 10251
Choral Music from Westminster-ARK 2123
Lemmens Vierne Dupré Widor-Advent 5009
The Sound of Musical lnstruments-ENY/AR-1
SQ
E. Power Biggs: Bach The Four "Great" Toccatas and Fugues-Columbia MQ 32933
Quadraphonic
Gala-Columbia ASQ-109
QS
Tchaikovsky: 1812 Overture and Romeo and Juliet-Turnabout QTV-S 34554
Gershwin: All the Works for Orchestra & for Piano & Orchestra-Vox QSVBX 5 132 (3 records)
UD-4
Bach: Concertos Brandebourgeois-Nippon Columbia 40X-9001-N
Pop Pop/4 Dimensions-Nippon Columbia 4KX-9007
A word of explanation about these records is necessary since many of them are not generally available at record stores. Both of the ARK stereo records contain excellent organ music, where the lowest bass pedal note recorded is 27.5 Hz (as measured with a General Radio Spectrum Analyzer). The record is available from Fulton Electronics, 4428 Zane Avenue N., Minneapolis, Minnesota 55422. The Advent record runs the gamut of classical organ music, with some fantastic bass pedal notes, the lowest recorded note being 23 Hz. Surface noise is non-existent on this record, which is available from Century-Advent, 878 Clarence Road, Cleveland, Ohio 44121. The ENY/AR-1 record is a superb recording demonstrating specific musical instruments that the Supex cartridge reproduced with great definition. Surface noise is non-existent on this record. The record is available for $5.00 from Acoustic Research, Inc., 10 American Drive, Norwood, Mass. 02062. The Quadraphonic Gala disc is not generally available, and was produced by Columbia Records for the Audio Engineering Society European meeting held in London earlier this year as a showcase sampler of SQ quadraphonic performances by leading recording artists of the world. The QS discs listed are excellent records, particularly the piano renditions, with which to demonstrate the transient response of the Supex cartridge. Since the UD 4 quadraphonic system has not yet been introduced in this country, the Nippon Columbia records are not easily available. Both of these recordings show the Supex cartridge to be capable of reproducing any recorded sound-stereo or quadraphonic! For those who have the Phase Linear 4000 preamplifier, the organ and the symphonic recordings are even more spectacular when the correlator, peak unlimiter, and downward expander (with the unlimit threshold properly adjusted), are in use. The Supex cartridge, in conjunction with the Phase Linear 4000 preamplifier, reproduces the bass spectrum on these records in an exceptionally clear and clean manner.
After listening to the records listed above, plus many others, as played with the Supex SD-900/E cartridge, we believe this cartridge is one of the finest stereo cartridges available today. Certainly the performance of the Supex SD-900/E is evidence why many audiophiles prefer the moving-coil principle.
-B.V. Pisha
(Audio magazine, Sept. 1975)
Also see:
ADCOM Crosscoil XC/VAN DEN HUL Moving-Coil Phono Cartridge (Equip. Profile, Jan. 1982)
A Clutch of Cartridge (Adcom, Grado, Talisman and Decca) (Feb. 1986)
Decca London International Tonearm & Mk VI Gold Elliptical Phono Cartridge (Aug. 1979)
Kenwood KP-5022 Turntable (Sept. 1975)
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