A buyers' guide to the best cartridges now available.
ANY ROUNDUP Of products is a fairly massive procedure, and there are certain to be omissions of individual reader's favorite products in the category, when one considers that in the directory 46 separate cartridges are listed, and these do not begin to include all the products of the several manufacturers. We estimate, for example, that there must be at least 65 different cartridges on the market from those manufacturers who are in the high fidelity industry. The only ones listed, too, are magnetic cartridges, since they have become the accepted standard for high quality sound reproduction.
Any testing of cartridges involves the use of phonograph records, and to be fanatically accurate, one should use a new record for each test--prohibitively expensive, considering that a frequency record, a square-wave record, and a wide-range test record must be used to provide a complete dossier on each cartridge. For frequency runs, the usual test record is the CBS STR-100. For wide-range measurements, the STR-120 is required, since the STR-100 covers the range only from 40 to 20,000 Hz. The STR-120 extends the range to 50,000 Hz at the high end, and down to 10 Hz at the low. Square-wave and intermodulation distortion tests necessitate the use of the STR-111 disc, which also has tracking information, although we used the STR-100 for tracking.
Additionally required are a 'scope, a graphic recorder, an a.f. voltmeter, an IM distortion analyzer, and a camera. The chart shows the "fixed" or static information about the cartridges tested, and will indicate that an ohmmeter and an inductance bridge are also needed addition to the equipment listed before.
Our first test was that of frequency response, using the STR-100 record. Response was first recorded for the left channel from 40 to 20,000 Hz, followed immediately by crosstalk response of the left channel to a right-channel modulation on the disc. Next we duplicated the measurement using the right channel of the cartridge. We then put on the STR-120 record and measured response on the sweep from 500 to 50,000 Hz, also on both channels, and followed this by running curves on response from 500 down to 10 Hz. We then measured the output from the cartridge at a signal of 3.54 cm/sec, 1000 Hz, and divided the figure obtained by 3.54 to obtain the relative output in mV for a stylus velocity of 1 cm/sec, which provides a comparative figure.
We then connected the IM analyzer to the output of the measuring preamp-which, by the way, is equalized to provide a boost of 6 dB/octave below 500 Hz, and to be flat above that turnover frequency. The recording characteristic of the STR-100 record consists of a straight line at a slope of 6 dB/octave from 500 Hz down, and flat above. A complementary equalization to this is not obtainable by a simple RC network such as is used in ordinary preamps, and if the usual RIAA equalization is used, the resulting curve will have a 1.5 dB "bump" at 500 Hz, and will roll off slightly below 50 Hz. This latter we accept, but a resonant circuit is necessary to flatten the "bump" at 500 Hz. All measurements are made through this preamp except for the square-wave photos, which require a wide-band linear preamp.
The IM measurements are done at two recorded levels--at +9 dB for the lateral bands of different levels--starting at +6 and increasing in 3-dB steps. The lateral bands of different levels-at +6 and increasing in 3-dB steps. The vertical portion has only three bands, +6, +9, and + 12. These IM bands are presented in duplicate with different pairs of frequencies-one is with 400 to 4000 Hz, while the other is with 200 to 4000 Hz. We have selected only the +9 lateral modulation at 200 and 4000 Hz, and for the vertical measurement, we chose the +6 modulation at the same pair of frequencies. Thus the measurements should not be considered "absolute," but only relative.
One series of bands on the STR-100 consists of a 100-Hz signal recorded at stylus velocities of 6, 12, 18, 24, and 30 cm/sec. To determine the tracking force listed on the chart, we measured the lowest force that would track the 30-cm/sec groove without breaking up. All these measurements were then followed by changing the preamp and projecting the square wave on the scope and photographing it. The square wave photos are unretouched and are simply prints from the negatives made of the patterns displayed on the scope. One should always remember that the curves and photos are those of a single cartridge (two at the most), and while they are likely to be characteristic of the entire run of the specified models, they cannot necessarily be guaranteed as such. This is a caution which should be remembered with respect to reports on any equipment. The only realistic curves and data should be the average of a large number of individual units, which is, of course, impossible in a limited compilation such as this.
ADC-25
This cartridge was profiled in the July, 1969 issue and is included in addition to the ADC 220 because we have long used it as a reference standard. Our unit has a frequency response which is within 1 dB up to 20,000 Hz! It uses the induced-magnet principle whereby the stylus does not move a heavy magnet; instead the magnet is fixed and the stylus moves a tiny magnetic collar which in turn moves between the pole pieces. Three styli are provided-two bi-radial or elliptical and one conical type.
Styli can be interchanged in a matter of seconds and, in theory, the critical user can get optimum results from his records. Available as ADC-26 with single elliptical stylus at a reduced price.
IM dist.: 1.6 lat., 2.2 vert. Tracking: 0.75 g.
ADC-220XE
This is a relatively inexpensive model, using the same induced-magnet principle as the ADC-25 described above. Response continues to about 35,000 Hz preceded by a small peak around 15,000 Hz. Separation is in the vicinity of 25dB at 1000 Hz, falling to 20 dB at 10,000 Hz. It is an up-dated version of the older ADC 220, having the new snap-on stylus assembly.
IM dist.: 2.5 lat., 5.4 vert. Tracking: 0.75 g.
Audio Technica
This unit may or may not be on the market under this name, but the product is used by a number of manufacturers in completed modular systems. Performance is reasonably comparable with other models-flat to about 5 kHz, then rising 4 dB at 9000 and remaining there to 20,000, then rolling off to-5 dB at 30 kHz. Separation is 22 4B through most of the range, rising to 26 at 3500 Hz, then gradually decreasing to 10 dB at 15 kHz.
IM dist.: 2.1 lat., 2.8 vert. Tracking: 0.75 g.
This model, AT-35X, is used in the Electro Voice Landmark 100 compact system, which was reviewed in the November, 1970 issue.
Decca 4RC
This cartridge was reviewed in June, 1970 and it has several interesting features. No cantilever is used between stylus and magnet which, it is claimed, results in more accurate tracing of the record grooves. Tracking weight is higher than most other top-grade cartridges but, according to the manufacturers, record wear is less due to the lower effective tip mass and use of a hand-polished diamond. The reviewer stated "it measures better and sounds better than any other pickup I have tested to date." Note that this product is manufactured by Decca Gramophone Ltd. of England, which is in no way connected with Decca Records, a division of MCA, Inc. of New York.
IM dist.: 2.1 lat., 2.5 vert. Tracking: 3 g.
B&O SP-12
This unit was profiled in the October, 1970 issue with a complete description of its mechanism. The stylus arm terminates in a "micro cross" which relays the flux to the four pole pieces. Response is smooth up to about 15 kHz, then rises some 4 dB at 21 kHz, after which it drops off to-10 dB at 30 kHz. Separation is around 20 dB dropping to 12 dB at 20 kHz. IM dist.: 3.2 lat., 4.0 vert. Tracking: 0.5 g.
Elac STS-444E
The Elac cartridge employs the moving magnet principle, invented by Dr. Ahrens of that company. The magnet--a tiny bit--is in the end of the stylus arm opposite the stylus, and its movements generate the flux changes through the four coils. The method is simple, effective, and relatively easy to manufacture.
The differences in performance of the various models using this construction testify to the ingenuity of the individual designers in adapting the method to their products. This cartridge is very flat up to 20,000 Hz, then drops off to 10 dB down at 26,000. Separation is better than 25 dB throughout most of the range, dropping to 15 at 10 kHz, and 10 at 20 kHz.
IM dist.: 3.0 lat., 4.0 vert. Tracking: 0.75 g.
Empire 1000ZE/X
The 1000 ZE was profiled in the November, 1970 issue, but the "X" model is still an improvement. Response is smooth, being 1 dB down at 10 kHz, 3 dB at 20 kHz, and about 8 at 30 kHz. Separation is better than 25 dB to above 10 kHz, and then drops to 15 at 20,000. Flatness of response is attributed by the manufacturer to the use of laminated pole pieces. The built-in stylus protector swings down to keep the stylus from contact with undesirable objects until you want to play a record. Then you swing the protector up and away.
IM dist.: 2.2 lat., 3.0 vert. Tracking: 0.5 g.
Goldring 800 Super E
This British-made product is praised by many users, and it is a pleasant sounding unit, fairly flat to 20 kHz, with a little trough at 5000 to 7000 Hz--about 3 dB. This is not an uncommon condition with cartridges, and probably results from damping to eliminate the main resonant peak, which in this unit is about 21 kHz. Separation is about 22 dB throughout the spectrum up to about 15 kHz, and then it decreases to about 15 dB at 20 kHz.
IM dist.: 2.1 Lat., 4.3 vert. Tracking: 0.75 g.
Grado F-2
Another new principle-this time using a "flux-bridging" generator. The generator itself is a toroidal structure with four gaps. The moving element is placed adjacent to the gaps but affects only the fringe field and acts much like a moving-coil pickup. Note the low inductance of the coils which are so placed as to neutralize hum pickup, thus eliminating the need for a shield. Response is flat and slightly rising to + 1 dB at 20 kHz, then drops to only 10 dB down at 50 kHz. Obviously this cartridge should be a logical choice for playing the four-channel discs. Separation is better than 25 dB over most of the spectrum, and is still at least 15 dB at 45 kHz.
IM dist.: 2.5 lat., 6.0 vert. Tracking: 1.0 g.
Ortofon SL-15
The only moving-coil cartridge in this survey, the Ortofon has long been on the market in two forms-with a transformer built into the cartridge itself, and with a separate transformer to be connected between the cartridge and the usual 47,000-ohm-input preamp. Note that in the chart, the inductance of the coil itself is shown as 350 microhenries, rather than in the usual millihenry range. Since the cartridge output impedance is only 2 ohms and its output is .04 mV/cm/sec, some additional step-up in voltage is required for the average preamplifier. We had both the separate transformer, and a new pre-preamp which is now available for use with the Ortofon, and we made measurements with both.
Response was similar, essentially flat to 10 kHz on the high end, then rising to a peak of about 15 dB at 23 kHz, then dropping back to flat again at 50 kHz. This would result in considerable "brightness," but with some speakers it might be considered desirable.
And for four-channel records, it would be ideal. The response peak, which is quite broad, actually, can be corrected readily by most tone controls, and especially so with some of the selective equalizers. Separation with either amplifier or transformer was about 22 dB throughout the entire range, in consideration of the increased response in the 20-30 kHz range.
The new pre-preamp consists of a single grounded-base transistor in each channel along with a very well filtered power supply and input and output jacks. It represents a desirable addition to the Ortofon, since it eliminates the possibility of hum pickup by the exposed-although well shielded-transformer.
IM dist.: 2.2 lat., 3.8 vert. Tracking: 1.0 g. with transformer: 2.6 lat., 4.0 vert.
Pickering XV15-750E
The top-of-the-line descendant of the first magnetic cartridge to attain popularity in the high fidelity field, the XV 15-750E has a very flat response to 10 kHz, then rises about 3 dB at 19 kHz and drops off to -10 dB at 30 kHz. Separation is better than 25 dB, then decreases smoothly to about 6 dB at 20 kHz.
The Pickerings employ the "Dustamatic" brush which rides in the groove ahead of the stylus and clears if from dust and lint--no more "rugs" on your styli. The new plastic fixtures for mounting simplify the entire operation of putting a cartridge into the head, since the fixture snaps into the head or attaches by a single screw .and the cartridge is simply snapped into the plastic fixture.
IM dist.: 2.6 lat., 2.8 vert. Tracking: 0.5 g.
Shure V15-II, Improved
This cartridge is the top of a long line of fine cartridges-individually tested before leaving the factory, and recognized as one of the choices of many audiophiles. When used with the recommended capacitance in the connecting cables-450 pF-this cartridge is flat within 1 dB to 20 kHz, then falls off rapidly, being down 10 dB at 24 kHz. Separation is around 27 dB throughout, up to 15 kHz, then decreasing to 15 dB at 20 kHz. The V15 II, Improved was profiled in the March, 1970 issue.
IM dist.: 2.6 lat., 2.8 vert. Tracking: 0.5 g.
Stanton 681 EE
This cartridge is known as the "calibration standard," and is used for this purpose in many recording studios and record factories. It is guaranteed flat within + 1.5 dB to 15 kHz, and a calibration is provided with each one as it leaves the factory. The one we measured was right on the button with the specifications on the calibration slip which accompanied it (which serves as a justification of our own equipment.) The separation is better than 25 dB from 60 to 2000 Hz, then decreases gradually and smoothly to 8 dB at 10 kHz, and remaining in that vicinity up to 20 kHz. The unit is beautifully packaged (as a matter of fact, packaging of cartridges is becoming as important as the packaging of cosmetics has been for years), with a gleaming metal case, plus a smaller metal case in which you can store your spare styli and also a small screwdriver. And with the exception of the Ortofons and Decca every cartridge in this survey has a user-interchangeable stylus, so you can go from conical 0.5-mil to various tip radii on elliptical or in some instances, to a 3.0 or 2.7-mil stylus for playing your old 78's. If you can remember that far back. The unit is shown with its dust brush.
IM dist.: 2.3 lat., 2.3 vert. Tracking: 0.5 g.
(Audio magazine, Feb. 1971)
Also see:
How we test a Phono Cartridge (Aug. 1972)
A Practical High-Frequency Trackability Test for Phono Pick-Ups (Aug. 1972)
Phono Cartridge Q's and A's--Mainly for Beginners (Aug. 1972)