Rega Planar 5 & Planar 7 turntables

I saw it coming back in 1996. That was when Rega introduced their full-bore assault on the state of the art of record replay, the Planar 9 turntable. The P9 was and is a superb product, but because it sells for $3900—more than five times the price of the company's bread-and-butter model, the venerable Rega Planar 3—its introduction created an enormous price gap. And that's not to mention all the numbers between 3 and 9 that have languished for so long: How could you not expect Rega to fill in the blanks with Planars 4, 5, 6, 7, and 8?

Two of those missing links have now been released to the American public, following their English debuts: the Planar 5 ($1295) and Planar 7 ($2595), both of which incorporate Rega's newly developed RB700 tonearm (also sold separately for $895).

Another clue to recent events was the increasingly modular nature of Rega's record players, a trend that became all the more obvious when the company updated the P3 with certain bits developed for the P9. More to the point, although their overall design sensibilities have remained both holistic and hierarchical (by the latter I mean that Rega has stood by the notion that it's best to upgrade certain aspects of a record-playing system before certain others), their newest and, arguably, cleverest design elements were discrete and self-contained. It would seem that such things as outboard motor controls, upgraded tonearms, and exotic platters could all be easily plugged into the basic Rega formula.

That formula calls for a low-mass player of the closed-loop sort, in which the key working parts—platter bearing, platter, tonearm, cartridge—are all connected together to avoid relative movement, thus preventing the loss or smearing of musical information. Materials in Rega turntables are also chosen so that, where resonances inevitably occur, they're spread thin, over a wide range of frequencies, and affect each component part in more or less the same way. If two parts in a closed loop resonate in drastically different ways, another sort of relative movement is created—and the results are much worse than if all the parts are allowed to resonate more or less unimpeded. An example would be when an undamped platter beneath a record is doing one thing while the damped tonearm holding the cartridge does another.

Another key element of all Planars is a low-mass, low-friction tonearm with a one-piece armtube and no lossy joints. That portion of the Rega formula deserves special mention, not only because the company's two newest record players use the same new RB700 tonearm, but because that arm is just the latest variation on one of the cleverest and most successful designs in all hi-fi.

Back in the early 1980s, Rega's Roy Gandy gambled that there would be an enduring demand for an affordable, mass-produced tonearm of extremely high quality. So he invested in the development of a one-piece aluminum-alloy tube that could be cast in such a way that consistency and low cost were guaranteed. Gandy also developed a rugged, low-friction bearing system (and a way to precisely but quickly "pre-load" it for each arm sample), a dense tungsten-alloy counterweight that concentrated more mass than usual near the fulcrum, and a clever downforce spring that actually pushes upward, to maintain a precise and consistent tracking pressure by countering, in part, the armtube's mass. The result was a family of superb arms, even the cheapest of which mates well with virtually any good turntable. Rega's tonearm is also the most successful perfectionist audio product in memory—since its introduction in 1983, more than a quarter of a million of them have been sold.

The new RB700 uses the same aluminum-alloy armtube as its forebears, although this one is painted silver instead of black. Other details have been refined, as well: The lateral bearing carrier has been redesigned, allowing more precise bearing adjustment and a surer, more rigid connection between the bearings and the rest of the arm. Also, an even-higher-spec bearing is used in the RB700. The three-point stainless-steel mount is carried over from the top-of-the-line RB1000 arm, for a more reliably tight connection to the plinth. And the bias mechanism, in which a small magnet tugs at a metal tang extended from the lateral bearing race, has been refined for a more consistent and precise antiskating force. The only difference between the arms supplied with the two new Rega record players is that the more expensive P7 gets an RB700 with the above-mentioned tungsten counterweight, while the humbler P5 gets an arm with the less exotic stainless-steel type.

Description
The Rega P5 is built around the same style of plinth developed for the P9: a low-mass "skeleton" CNC-machined from a fibrous wood composite, then sandwiched under high compression between thin sheets of satin-black phenolic. A threaded brass bearing well, nicely machined on the inside and fitted with a steel ball bearing, bolts to the plinth with a single nut. The 0.3" steel bearing axle, ground flat at one end to mate with the ball bearing, is pressed into a 4"-diameter molded hub—a part that will look familiar to anyone who's owned a Planar 2 or 3 of any vintage, as will the 11.6"-diameter glass platter.

The drive motor is also rigidly fastened to the plinth (in days gone by, this was suspended from the rest of the turntable with a "cradle" made from an extra drive belt), and its armature is topped with a machined alloy pulley, stepped so that platter speed can be changed from 33rpm to 45rpm by moving the belt. The motor is an AC synchronous type, but not the usual 110V sort: In another nod to their flagship, Rega has equipped the P5 with a 24V, 50Hz motor.

The P5 is supplied with an outboard transformer (a wall wart, but a nice one) to bring the household current down to the necessary 24V. From there, although an onboard phasing circuit would be sufficient to get the motor turning in the right direction, Rega incorporates a circuit to split the incoming AC into two separate phases, with an adjustment for the angle between them that can be used to dial out motor vibrations. It's the electrical equivalent of the way a violinist might tune an instrument by comparing one string's harmonic with that of another string, or a tuning fork: She trains herself to hear a "beat" created by the slight mismatch between the two waves, which can be eliminated by adjusting one of them with great precision.

The basic Rega P5 lacks the circuitry to re-create a 50Hz wave for its European motor, so American buyers get a smaller-diameter motor pulley than their English counterparts. But P5 buyers in any country can upgrade their new turntable at any time with the addition of an optional outboard power supply, which then derives its own power from the 24V wall-wart. The Rega TT PSU power supply ($345) does, in fact, create its own motor reference signals with crystal oscillators, and it supplies the two separate phases with greater accuracy than the comparatively simple onboard circuit described above. (The TT PSU powers the Rega P5 through a dedicated four-conductor socket, as opposed to the two-conductor socket for the wall wart.) The optional supply also generates a separate frequency for spinning the platter at 45rpm, thus forever relieving the P5 owner of the drudgery of pulley-swapping.

For its part, the P7 turntable appears closer to the top of the line than the bottom. It, too, starts with a P9-style plinth, but builds on it with a P9-style platter bearing: a single-point design not unlike that of the Linn LP12, fixed to the plinth at three points. The bearing axle, also approximately 0.3" in diameter, is pressed into a 4"-diameter subplatter beautifully machined from aluminum alloy, and somewhat taller than the P5's plastic hub. The subplatter's top surface is milled into three separate, small plateaus, to support a platter that's ground and diamond-lapped from an exotic and extremely hard ceramic oxide. The idea of a ceramic platter originated with the P9, and is said to be that flagship turntable's single most expensive part. The P7's platter is something of an economy version. While shaped to concentrate its mass at the periphery—a means of enhancing speed stability through rotational inertia—the P7's platter is a flat and comparatively featureless ceramic plate, to which 18 separate ceramic discs are cemented to optimize weight distribution.

The P7 uses the same 24V, 50Hz motor as the P5, but its outboard TT PSU power supply is a standard feature—and it, too, is powered by a 24V wall wart. But in the US, a TT PSU intended for a P5 does not work with a P7, and vice versa—despite a complete lack of labeling to this effect. Optional power supplies intended for American P5 turntables remain 60Hz devices, in deference to the turntable's smaller motor pulley. The P7 motor, for its part, gets the big pulley—and a well-machined one it is, with two grooves, for two belts.

Incidentally, both new turntables feature the same simple and floppily hinged dustcover that's been used on Rega Planars for more than 20 years, but because the new plinth isn't large enough to support such a thing, a frame-style surround is fastened to the front and sides. Unlike that of the Planar 9, which is CNC-machined from a variety of hardwoods, the P5/P7 frame is made from aluminum, finished in satin clearcoat or satin black. The P5 and P7 also use the same rubber feet—cleverly nubbed things that exhibit different isolation frequencies depending on how much mass is concentrated above them—except that, on the P7, they're turned upside down and fitted with alloy trim rings. I'm not sure which I admire more: Roy Gandy's obvious sense of thrift for buying-in staggering quantities of parts, or his ingenuity at finding such a variety of uses for those parts over the years.

Setup
It's also apparent that, at some point in his career, Roy Gandy bought enough cartons and packing inserts for a half million Planar turntables: Those, too, never seem to change, right down to the red cellophane tape Rega has used to secure their subplatter spacers since the dawn of time. But I'm not complaining: It works. A loose dustcover hinge on the P5 was the only glitch I encountered, and remains the only shipping-related glitch I've seen in more than two decades of owning and writing about Rega record players.

With the P5 and P7, as with all Rega turntables, the platter bearings are oiled and assembled at the factory, and the tonearms are precisely mounted. Apart from installing the cartridge of his or her choice—which is, in fact, the retailer's job—all the owner has to do is remove the cardboard subplatter spacer, set the platter in place, balance the tonearm, dial in the correct downforce and bias, and connect the wall wart and, where applicable, the outboard power supply. It takes all of 10 minutes, not counting cartridge installation.

Both of my review samples were fitted with fresh samples of the Rega Exact cartridge ($550), a moving-magnet type I know well, having owned one for years. After auditioning the 'tables as furnished, I also swapped in my lingering review sample of the Dynavector DV-10X5 ($360), a good high-output moving-coil cartridge that has historically appealed to Rega owners. In the P7, I also tried my Supex 900 Super and Helikon Mono low-output MC cartridges. None of that was terribly hard to do, but the job was complicated by the need, with most non-Rega cartridges, to raise the arm relative to the plinth using specially machined spacers, available from the dealer or distributor. My Supex, for instance, required a 2mm spacer, whereas the Dyna required the 4mm size. The spacers are machined dead-flat, and cost $39 a pop; Rega owners are well advised to keep a couple on hand, and not to cheap out with dime-store washers.

There's also the matter of alignment. Rega's own cartridges, in addition to not being very tall, all use a three-bolt mounting scheme, and are designed to exhibit perfect alignment when all three bolts are used to fasten them to any Rega tonearm. But by "perfect alignment" I mean perfect Rega alignment—which does not jibe with the Baerwald geometry that is the basis of most aftermarket alignment protractors. Like the others, Rega's alignment scheme starts with a known pivot-to-spindle distance and derives a precise offset angle and stylus "overhang," intended to create two zero-distortion or "null" points on the LP's grooved area. But Rega's system, which involves a much shorter overhang than Baerwald's, seems intended to place the outermost null point much closer to the LP's lead-out groove, apparently to counter the higher levels of distortion associated with the smaller groove radius. (The P5 and P7, like all Rega turntables, are also supplied with a cardboard alignment template, for owners who wish to install non-Rega cartridges—but these templates, too, are based on Rega's own alignment system.)

Company Info
Rega
US distributor: Sound Organisation
11140 Petal Street, Suite 350
Dallas, TX 75238
(972) 234-0182
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