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A look at todays record-playing equipment - This Month's Shopper - Off Duty / Europe / December 1972 - By THOM PRINGLE

AFTER YOU'VE CHOSEN everything else for your hi-fi system, you'll probably choose the unit that will be put in front of everything - the turntable.

It's one of those weird twists of fate that turntables don't share the same glory as receivers and loudspeakers even though they are tremendously sophisticated pieces of equipment.

As a matter of fact, audio equipment salesmen have frequent cases where customers will buy an entire audio setup and completely forget the turntable. On the other hand, we were recently told that, on occasion, hi-fi novices buy just a turntable, take it home and can't figure out why no sound comes out of it.

So, in order to help put the turntable in perspective, perhaps we should explain just what you should expect from your"record machine."

Many people still have visions of the popular "phonograph" which was an all-in-one gadget - once you bought it you were ready to listen to records.

It had a built-in amplifier and speaker - maybe even a built-in tuner, too. Undoubtedly, this is what people are thinking about when they mistakenly buy a lone turntable and expect it to produce sound.

Of course, it's still possible to buy a "phonograph" but, today, if you want a high quality all-in-one unit for your home, you want what is called a "system" - either compact or console.

Thus, we'll not only discuss turntables, here, for those of you who actually want a turntable, but also compact systems for those of you who want to take the no-muss, no-fuss way to stereo or 4-channel.

The terminology involved here may become a little confusing, as it often is in hi-fi, because of the rapid developments which have taken place in the field of sound reproduction and electronics.

First of all, the term "record player" is not used often since most people tend to associate it with phonographs. Therefore, the word "turntables" is used to cover the entire field of high-fidelity record turners.

Within this field, however, the word "turntables" is also used for a subcategory and denotes those record turners which do not have the capability of changing records.

Among the turntables available are completely manual turntables with no automatic functions, semi-automatic turntables which usually shut off automatically at the end of the record, and automatic turntables which automatically cue themselves and shut off at the end of the record.

Those record "tuners" (?) which can automatically play their way through a stack of records are called "changers" and the current trend is toward convertible units in which the changer may be converted to an automatic turntable by changing its center spindle.

In these cases, the unit will most likely be called an automatic turntable/changer, although some manufacturers prefer to call it just an automatic turntable.

A great deal of work has been put into turntable motors and their associated parts and three general types of motors are now used in modern turntables.

The induction and synchronous motors depend on line power for their stability - the induction motor on line voltage and the the synchronous motor on the frequency of the line power.

If the line voltage or frequency vary, then these motors will vary their speeds respectively. Similarly, if you move to a country with a different voltage and line frequency, you will most likely have to have the idler in your turntable changed as well as changing the power connections to the motor.

Nevertheless, these motors are used in almost all turntables and give entirely satisfactory performance and, if carefully designed, can give outstanding performance.

The third, newest and most expensive drive system is the electronically controlled system. This method uses a built-in power supply controlled by an electronic circuit which constantly monitors the speed of the turntable and varies the output of the supply to correct the speed of the turntable.

This drive method is extremely accurate, independent of line voltage or frequency and allows incorporation of special motors with very low speeds or especially good performance characteristics. For the person who demands high, long-term performance and is willing to spend the money, this drive method is very attractive.

The very latest high-quality manual turntables usually offer only two speeds (33 and 45 rpm) since most audiophiles use only 33 LP discs and on occasion play a single 45. In the future, you'll probably see more units which limit the number of operating speeds.

To judge the quality of performance in a turntable, two measurements are generally used, flutter and wow (short-term speed variation) and rumble (vibration).

You will find rumble stated in two ways, weighted and unweighted. The difference between the two is not important to you if you remember to compare the same type of rumble when comparing turntables.

Most good turntables today can offer a rumble figure of -55 dB (weighted) or -40 dB (unweighted) - the higher the figure, the better. Look for a flutter and wow figure of 0.1 per cent or less.
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Very few manufacturers offer a turntable without a built-in tone arm. A few years ago, because the tone arms supplied with turntables were on the clumsy side, it was popular for an individual to buy a separate tone arm and mount it himself - but those days are pretty well in the past.

The tone arms which are supplied with turntables now are very sophisticated and have all the adjustments necessary to adapt to almost any kind of cartridge. However, if you're a purist and have special demands, you can still buy separate specially-built tone arms - you'll find a few listed in this SHOPPER.

Tone arms have gained increasing importance in recent years, especially with the advent of 4-channel systems. With the tremendous improvement in reproduction systems, cartridges had to be improved to keep pace and the new breed of delicate, low-mass, light-touch cartridges was born.

These cartridges should not be subjected to heavy external force and, therefore, need a special kind of tone arm to carry them. The tone arm not only has to hold the cartridge in a particular vertical plane but horizontal as well.

For this, the quality tone arm today has adjustments for vertical balance (counterbalance), to control the tracking force, and for horizontal balance (anti-skate) to prevent unequal side pressures from being exerted on the stylus.

A few special arms are offered including articulating and straight-line arms. In both cases the arms are so designed that they maintain the cartridge at the same angle with respect to the grooves at any point across the record. This eliminates tracking error but may introduce unusually complex mechanisms and uneven side pressures - so these types of arms can have their drawbacks, too.
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Special features on turntables have become pretty well standardized but can be very helpful to the audiophile.

The cuing control, which mechanically raises and lowers the tone arm, allows you to have precise control over the positioning of the stylus and thereby accomplish precision cuing. Many of the cuing controls are viscously damped so that the tone arm gently floats to the surface of the record preventing any damaging collision between the two.

Many turntables offer a variable speed control which slightly varies the speed of the turntable. Used in conjunction with a strobe pattern (also built into some models) it allows precise speed setting - not absolutely necessary, but nice.

Almost all models have a plug-in cartridge shell. With this feature you can keep several types of cartridges, if you want, and instantly switch cartridges depending on the situation.

Phono cartridges are probably receiving the most attention of any part of the turntable ensemble. 4-channel is responsible and either matrix or the CD-4 discrete method put unusually heavy demands on a cartridge.

The matrix system involves extremely complex phase patterns, while the CD-4 system uses a 30k Hz carrier signal with modulated signals extending up to 45k Hz. This means that your cartridge has to be unusually versatile and offer outstanding performance if you have a 4-channel system.

Not all cartridge manufacturers give the same information concerning their cartridges, so you may have some trouble making comparisons. Generally, though, you will be able to find frequency response figures (even if unreferenced), channel separation, tracking force, stylus shape and compliance. On occasion, distortion figures are also given.

In selecting a cartridge, look for a minimum frequency response of 20-20k Hz, minimum channel separation of 25-30 dB, and, generally speaking, it is desirable to keep the tracking force at 2 grams or less.

The degree of ease with which the cartridge responds is known as "compliance" and the figure will usually look similar to this: 25x10-6 cm/dyne. Naturally, the higher the figure, the greater the compliance of the cartridge and the easier the stylus will be able to follow the signal in the groove. As a reference for compliance, keep in mind that 35x10-6 cm/dyne is considered high, while compliances below 20x10-6 cm/dyne are usually considered as being somewhat low.

Two kinds of styli are generally available today, the spherical and the elliptical types. JVC's Shibata stylus, which has a tip designed to contact more groove surface area is available on a limited scale. Audiophiles are now generally using the elliptical stylus since its tracking ability is much better than the spherical type.

There is a wide range of compact systems available to the person who wants to buy a stereo or 4-channel complete system and know that everything has been pre-matched for best performance.

To qualify for our compact system SHOPPER a system must include at least a turntable and amplifier - most will also have speakers and a built-in tuner. Some require you to select speakers or they have built-in cassette or cartridge tape recorders. You can have either stereo or 4-channel systems, various output powers, home-type or portable units and, usually, provisions for external components.

All this means that you can find about whatever you want in a complete system. Because of the diversity of features, it is almost impossible to give general guidelines for selection of a unit. The best idea is to check the listings for a unit which has the components you want, then try to find the unit in your nearest purchase point and listen to the unit perform.

In this SHOPPER you can find the "record player" you want regardless of your definition of that term.

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