Test Records and Demo Discs, Part Five

Test Records and Demo Discs, Part Five

Written by Rich Isaacs

In the days before digital music, the primary medium for sound reproduction was vinyl records. Sure, there were some who preferred reel-to-reel tapes, but they were in the minority. The turntable was king, and it had to be properly set up. Any audiophile worth his (or her) salt owned at least one or two test records specifically designed for that task.

Over the years, I’ve collected a disproportionate number of such discs (it helped that I worked in record stores for much of my adult life, so I could obtain the ones I wanted at reasonable prices).

In the first part of this series (Issue 205), the focus was on test records issued by record labels themselves. In Part Two (Issue 206), albums from phono cartridge manufacturers were featured. Part Three (Issue 207) looked at records issued by speaker companies. Part Four (in Issue 208) included LPs from publications. This edition pulls from a variety of sources, including some albums that weren’t even meant to be played (read on).

  

 

 

Audio System Test Record (1977 – 78)

One of the companies providing initial competition for Mobile Fidelity in the half-speed mastering re-issue world was Nautilus. Their offerings were called “Superdiscs.” This piece of vinyl is touted as “The First Complete Audio System Test Record.”

From the liner notes: “Most ‘test records’ are designed by engineers to do exactly what the name implies: to test specific functions of a cartridge, tape deck, speaker, etc. Fully evaluating the results from such tests usually requires sophisticated testing equipment and more than a basic, layman’s knowledge of the tests, their purposes and the significance of the results…The Nautilus Audio System Test Record has been specifically designed to solve major problems that plague an audio system. No test equipment is necessary and the instructions are simple to follow. Your ears are the final judge in these tests, and the overall improvement to your system is audible and significant.”

Unfortunately, I bought my copy as a used record, and the original owner must have kept the instruction booklet, making it impossible to fully evaluate the claims on the back cover. Well, dang!

 

 

 

 

 

Soundcraftsmen Instructional Test Records (1976?)

Before tone controls became anathema to high-end manufacturers and listeners (we must retain the purity of the original recording!), graphic equalizers were enjoying a surge in popularity. The idea was that, through more precise adjustments of particular bands of frequencies, deficiencies in equipment and room acoustics could be mitigated.

Soundcraftsmen equalizers were considered one of the top consumer products in their category. Early models controlled fewer than 10 bands per channel, which still represented a level of adjustment well beyond the bass and treble tone controls found on most components of the time. Later models featured up to 21 bands (on one pro model, allowing for one-third-octave control). In addition to sliders which adjusted the frequency bands, there were master volume sliders for each channel.

In the 1970s, I owned a Model RP2212 (a ten-band unit), and used it primarily to tame a bit of bass boom. At the time, I had a Marantz 1060 integrated amp driving Altec Lansing bookshelf speakers. Equalizers were often misused by boosting a number of bands without a concurrent reduction in overall level, resulting in a louder output. When comparing the equalized sound to the unequalized sound, the former would be louder, and therefore mistakenly perceived as better. (All other things being equal, the brain will usually interpret louder as better.) I was always careful to compare the input and output signals at equal levels.

This album was supplied with the unit, and included the charts shown for recording and easy adjustment of the equalizer settings for various conditions (or even certain recordings).

 

 

 

 

Geo-Disc by Mobile Fidelity Sound Lab (1981)

Now we get to one that shouldn’t/can’t be played. This platter is exclusively for the setup and alignment of your phono cartridge. There are no audio tracks on it. If you were to set your stylus down on it while it was rotating (which it shouldn’t be), you could kiss that expensive bit of diamond “jewelry” goodbye.

The design is pretty ingenious, allowing for very precise alignment without any test equipment other than your eyes. The long ridge line to the right of the center hole should point directly to the center of the lateral tonearm bearing. The cartridge is to be moved forward and back to a position so that the stylus tip rests in the tiny white circle in the grid. Then the cartridge can be twisted, if necessary, until the sides of the cartridge are parallel with the gridlines. Lastly, the cantilever should be aligned with the shorter ridgelines.

 

 

 

 

Telarc Omnidisc (1982)

One of the pioneers in digital recordings, Telarc issued this two-disc set that was distributed by Audio-Technica. Side One is another “don’t try to play me” affair. It features a series of etched and labeled parallel lines on either side of a radial line. It calls for knowing some alignment positioning information that may or may not have been supplied with the user’s tonearm/turntable. In addition, one would likely have to take measurements from the arm bearing and/or the spindle, down to the millimeter. It is nowhere near as user-friendly as the Geo-Disc.

Side Two is comprised of 44 test signals, including a 1,000 Hz tone, pink noise, phasing tests, and even a silent track to evaluate overall system noise. It has strobe lines printed on the label for checking speed accuracy.

Side Three involves tracking tests, using excerpts from five Telarc classical recordings. Each passage is repeated four times, with each repeat being cut at least 2 dB higher than the previous one.

Side Four is labeled “Imaging and Music,” and features two musical passages. The first is the Fugue from Benjamin Britten’s “Young Person’s Guide to the Orchestra,” with Leonard Slatkin narrating and conducting the St. Louis Symphony Orchestra. The second is a performance of The Beach Boys’ “Good Vibrations,” performed by the group Papa Doo Run Run (a band variously described as a tribute band or a California beach party band). [The latter cut is a tracking torture test – at a CES one time, an exhibitor played it and the arm literally leapt out of the groove. – Ed.]

The final installment in this series will feature PS Audio’s The Stereo, a test record with its accompanying book, along with a few older discs.

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