Turntable Buying Guideline

The latest emerging audio technology is…The turntable!

With the current resurgence of vine-yule records, turntables are again a hot item. And while most of the turntables floating around out there are survivors that were manufactured years (decades, mostly) ago, there are plenty of new ones in all price ranges from a few hundred dollars to “don’t ask”. As a grizzled veteran who bought his first audiophile (for that era) turntable in 1963, I witnessed the proliferation and improvement of the turntable, then its demise with the cold ascension of digital, and now, the turntable’s rebirth.

My first decent ‘table in ’63 was a Bogen B-60, which featured a 7-3/4 lb. platter which was basically a big flywheel. It was driven by an idler wheel, which was a Fred Flintstone technology killed by the advent of stereo, which shined a light upon what is known as “vertical rumble.” Rumble is the low bass junk caused by motor noise transmitted through the drive system into the platter, and picked up by the cartridge. When I played records, it sounded as if a garbage truck was parked and idling 100 yards from my house. Budding audiophile kid that I was, I had multiple headshells, and I often swapped cartridges; Pickering, Shure, Stanton, ADC, and even a vintage GE that was one of the first magnetic cartridges. For a hobbyist, a turntable is far more entertaining to futz with than a CD player.

The advent of the CD around 1980 caused turntable sales to flatten out for a few years, and then, ultimately to plummet. I sold hi-fi at retail in those days, and my customers wanted to make sure the CD was not a fad before they dragged their turntable out to the garage, attic, or curb. I never would have predicted the return of the turntable any more than I would have predicted the return of lawn darts, the Sony Sports Walkman, or WordPerfect. And if you don’t have an old turntable anymore, you may be in the market for one…

Choosing the right turntable

So what should you be looking for? The better turntable/arm/cartridge combinations will spin the record at an accurate speed, have good isolation, have nice, low-friction tonearms, and they will have compatible cartridges of good quality.

The two general types of turntables are direct-drive and belt-drive, and there are excellent and horrid examples of both. In a direct-drive model, the motor almost always sits under the center of the platter and it drives the platter “directly.” In a belt-drive turntable, the motor is generally off to the side and the platter is driven from the capstan of the motor, usually to an inner pulley or the outside of the platter via a belt. The belt can also be a fiber or some other exotic material. If Harley Davidson made turntables, they would probably use a chain-drive and they would run slow, but I digress. Before you send me hate e-mail, I love my Road King Classic. (Disclosure: I don’t actually have one.)

One of the most important requisites of a turntable is that it provide isolation from both mechanical and acoustical feedback. Direct-drive turntables generally aren’t  as well isolated because they lack the suspension system found in most belt-drive turntables, and in a DD ‘table the motor and platter are mechanically coupled. However, direct-drive ‘tables can offer decent isolation and freedom from feedback through having substantial mass. I currently use a vintage high-end DD turntable that weighs 30 lbs., and it has good freedom from boomy feedback through sheer mass. Belt-drive turntables don’t need mass to isolate effectively because the sprung suspension and belt offer isolation of the motor from the platter. That said, the worst turntable you can buy is a very lightweight direct-drive model; the kind that flooded the market at the $100-$250 price point in the mid-‘80s. They would boom along with the music due to undamped sympathetic vibration. The easiest way to find out if a turntable is poorly isolated is to lightly tap on the base (called the “plinth”) with the volume at around 1/3 with no record on and listen for a loud thump from your speakers. A flimsy direct-drive table will act like a microphone and pick up bass frequencies which you’ll hear as extra, annoying “boom” or even damaging runaway feedback.

Editorial Note on Acoustic Feedback:
Acoustic feedback occurs when a sound loop exists between a turntable and loudspeakers. In this example, a bass signal received by the turntable (mechanically or airborne) is amplified and passed out of the loudspeaker. The sound from the loudspeaker can then be received by the turntable again, amplified further, and then passed out through the loudspeaker again. 

The turntable/tonearm/cartridge interface

Possibly the most overlooked area of assembling a turntable/cartridge system is matching the cartridge to the tonearm. Two properties must be matched; the compliance of the cartridge and the effective mass of the tonearm. The “compliance” of the cartridge refers to the ease of deflection of the cantilever, which is the miniature tube that holds the stylus; the needle. It’s the thing that you accidentally bend or break through abject carelessness, and then you curse loudly and your dog hides under the bed. At least mine does.

The “effective mass” of the tonearm is determined by the weight of the tonearm from the pivot to the end of the arm. More mass moved farther from the pivot increases effective mass. Some turntables and all separate tonearms publish an effective mass number, which is good because few of us would be able to figure it out on our own. Including, especially, me. Seriously, you can find articles online that go into this in painful detail; articles penned by folks who know a great deal about the physics of turntables, arms, and cartridges.

If you look up a particular cartridge’s compliance, you’ll see what appears to be a cryptic formula. Ignore it, other than the first two digit number. (Example: 20 x 10-6 cm/dyne.) A low-compliance cartridge will have a number below 11 or 12. A moderate compliance cartridge will fall between 13-18; and a high compliance cartridge will be in the neighborhood of 20-25. This number of the compliance has nothing at all to do with quality, but the compliance has to match the tonearm. The general rule is “high compliance cartridge, low mass tonearm,” and “low compliance cartridge, high mass tonearm.”

The combined resonant frequency of the tonearm, cartridge, mounting hardware, etc. should fall within the 8 Hz-12 Hz range. If it’s lower than that (high mass arm with a high compliance cartridge) record warp and foot stomps will cause your woofers to move uncontrollably. Conversely, if the resonant frequency is too high (15 Hz-20 Hz range) music, warp, record noise, etc. in the lowest of audible ranges will resonate with the arm/cartridge, also causing huge speaker excursions. If a note coincides with an audible tonearm/cartridge resonance the cartridge can mistrack or at the very least, you’ll hear an exaggerated boom in the bass.

The best ways to avoid poor cartridge/tonearm mating are either to buy a turntable with the appropriate cartridge pre-mounted and balanced, or refer to an online chart such as this one to guide you in matching an appropriate cartridge to the arm:
http://www.resfreq.com/resonancecalculator.html

The tonearm will limit you to a range of choices, and you can’t go beyond that range and expect good results.

Cartridge types

There are two basic types of good cartridges; moving coil and moving magnet. You may have heard of ceramic cartridges, but they are to be avoided because they’re antiquated, crappy, they’ll destroy your records, and they won’t work in magnetic phono inputs. But, other than that…

If you can recall Faraday’s Law of Induction, movement within an assembly that includes a permanent magnet and a coil will induce voltage in the coil. When playing a record, the stylus moves in concert with the undulations of the record groove, and that moves the cantilever, which is connected to either a magnet or a coil. To induce that voltage in a moving coil cartridge, the magnet is stationary and the coil moves. In a moving magnet cartridge, the coil is stationary and the magnet moves. Neither design is inherently better; just different. A moving coil cartridge almost always has lower output due to the desirability of lower mass of the coil and the resulting lower output. Almost all MC cartridges require a “head amp,” separate phono preamp, or step-up device because they don’t provide enough juice to properly drive the phono input in your preamp or receiver. Some audiophiles justify the lower output, slightly higher noise, and added cost of another component because moving coil cartridges are known for extraordinarily detailed and articulate treble.

Most cartridges, however, are higher-output moving magnet designs. MM cartridges are usually higher in compliance, and they work better in lower-mass tonearms. MC cartridges can keep the important resonant frequency between 8 Hz-12 Hz only in higher-mass arms. If you are at all confused, see a local specialty dealer (if you’re fortunate enough to still have one), or refer to the link posted above. There’s no need to dial in the arm and cartridge to perfection, though. Getting close is usually just fine.

Setup

If you don’t purchase a package that includes the arm and cartridge already set up, there are many tasks for you to perform. You should have an alignment protractor for getting the cartridge aligned properly within the tonearm’s headshell. You should have a stylus pressure gauge for setting the recommended stylus pressure correctly. Most turntables suggest you set the anti-skate compensation the same as the stylus pressure (1.5 grams; set anti-skate to 1.5, etc.), but a blank anti-skate disc is a good idea because it will be more accurate. Anti-skate adjustment counteracts the vector force that pulls the stylus tip inward in the record groove as the record spins. It helps keep the stylus centered in the groove, which yields the best possible sound and the least amount of record wear.

If you properly adjust cartridge alignment, stylus pressure, and anti-skate, your records will sound better and they’ll last longer. Some arms allow you to adjust vertical tracking angle through raising or lowering the tonearm at the base. The idea is to match the angle of the cutting lathe that made the record, and that is usually 15-degrees. Unless you’re really a good DIY person, you may want to leave the arm height alone. A novice can easily convert a tonearm and cartridge from a record playing device to a record chisel. If you are near a brick and mortar audio store, give them a shot at selling you something, or see if they’ll set up your existing turntable if they happen to have a turntable maven working there. (Most of us are dead.) It will be well worth the price if they can set up the turntable system properly. Don’t underestimate the importance of a professional turntable setup.

Linn Sondek LP-12

Which turntable to get?

There are many vintage used turntables available, some with old cartridges. If you don’t mind installing and calibrating a new cartridge, that might be your best bet. An old Linn Sondek LP-12 can be made to sound exquisite, but they are somewhat difficult to set up properly. One safe bet is a vintage B&O turntable with a conventional radial (pivoting) arm. The B&O arms were extremely low mass, and the cartridges were very high compliance, (as high as 35 x 10^-6 cm/dyne) and the combined resonance was known; around 14 Hz. They also offered amazing isolation from bass. The B&O cartridges sounded very natural and even somewhat dull and unexciting to some listeners. One might also look at vintage Thorens (TD-125 and later), Oracle, Dual, Phillips, or one of those massive DD ‘tables from the Japanese companies. Any old Micro Seiki; direct-drive or belt; would be a great choice.

Micro Seiki SX-8000 II

It’s encouraging to see a new wave of reasonably-priced and very good audiophile turntables from Rega, Music Hall, Pro-Ject, and others. They’re superior to entry-level turntables of the ‘70s and ‘80s in most cases.

Rega RP6 (left) and Rega RP3 (right)

Time to spin some vine-yule

After making sure you bought the right turntable, compatible cartridge, and you get everything installed and calibrated correctly, you’re ready to enter the old-fashioned, funky, wonderfully nerdish world of records. Make sure you also have (at least) a decent handheld record cleaner and a brush-on stylus cleaner. I won’t debate the relative sound quality between records and CDs because I’ve done that in previous articles. But if the record was mastered well, good quality vinyl was used, and you’ve kept your records in pristine condition, vinyl records can be a very rewarding format. The return of vinyl pleases me, but it was also quite a surprise. A nice surprise.