The Kuzma 4 Point Tonearm Does the Heavy Lifting
(This review originally appeared in Stereophile magazine in "Analog Corner") No one has ever accused Franc Kuzma of designing glamorous audio jewelry. His turntables and tonearms are industrial strength examples of engineering know-how and machining excellence.
For those appreciative of such things his products are truly beautiful—even if they are not festooned with chrome, wood and sleekly polished surfaces.
If looking at the pebbly Darth Vader-ish black 4Point doesn’t get your analog juices flowing, perhaps the innovative design behind it will. But first, this message:
The problem with gimbaled (fixed) bearings is obvious: the perfect gimbaled bearing will have zero “chatter.” It also won’t move. Therefore, even the best of them will have some chatter. Bearing chatter has an enormous impact on tonearm sound quality.
During a visit to Rega’s tonearm building facility some years ago, I watched assemblers randomly pick bearings from a bin and test tolerances. Though all were from the same manufacturing batch, quality varied widely.
The best went into Rega’s top arms. The rest were sorted by tolerance for use in lower priced arms. Change nothing but the bearings and you significantly change the sound.
Though unipivot bearings are not fixed, unipivots can have their own form of “chatter” if sufficient mass isn’t brought to bear on the point/cup interface or if the quality of the parts isn’t sufficiently high. Unipivots can also have stability issues, with the arm moving in other than the desired vertical and horizontal axes.
Graham Engineering, for instance uses an ingenious magnetic stabilizer system rotating on a high quality horizontal bearing (that will have a degree of “chatter”) to prevent unwanted movement and create a gimbaled bearing-like unipivot. Other unipivot manufacturers have their own fixes, including stabilizing outriggers similar to what high wire artists use. Continuum’s Cobra and Copperhead arms employ a secondary vertical pivot riding on a sapphire “swash” ring affixed to an ABEC7 bearing (which of course will have a degree of “chatter”). It provides both stability and means by which azimuth can easily be adjusted.
Then there are the so-called “tangential tracking” tonearms. The best of these use captured air bearings that move smoothly on a fixed cylindrical rail. A less satisfactory method fixes the air bearing and moves the massive rail. Others blow air through tiny holes in the rail over which slide passive cylinders buoyed by the pressurized air captured within. Another design uses a tiny trolley-wheeled device that slides along quartz rails. Still others move the arm and maintain tangency via a motorized servo-mechanism.
All of these designs look cool and appear to be “linear trackers” but few are. Most actually “crab” their way across the record surface, creating a series of microscopic arcs that produce more and repeated tracking error than does a well designed and set up pivoted arm.
Again, unless the bearing is so tight it won’t move, the spacing necessary to allow movement in such arms, produces fore and aft, or up/down motion, or “yaw” along the cantilever’s zenith angle—all at a microscopic level invisible to the naked eye.
Differing horizontal and vertical masses produce their own serious sonic and mechanical issues as does the need to move the tonearm wires across the record surface along with the arm.
In my experience with air-bearing type arms, only those using captured bearings that maintain uniform pressure around the air gap can truly be called air “bearing” arms and only those can truly maintain tangency. The others are hover-crafts of one sort or another. Don’t get me wrong: some of those can work pretty well and sound good but I’m not convinced they can truly maintain tangency to the groove.
And even those pressurized type air bearings that do maintain tangency have another serious problem: the air has to go from high pressure to ambient room pressure in a matter of inches as the pressurized air reaches the annular gap. If you want to see what that’s like, blow up a balloon and let it go. Consider that behavior and imagine what’s happening at the gap as the bearing moves “frictionless” across the record surface and the air struggles violently to escape and reach ambient room pressure. The only captured air bearing arm that compensates for this issue, to the best of my knowledge and at great expense, is the arm on Andy Payor’s “out of print” Rockport Technologies System III Sirius.
What I’m trying to say is that when you read some of the online hype for one technology or another as a “breakthrough” in perfection and the description doesn’t attempt to deal with any of the inevitable downsides of that “breakthrough” technology, don’t believe what you’re reading!
The 4Point Point
The tech-agnostic Mr. Kuzma builds very fine fixed gimbal, unipivot and captured air bearing arms. These are all accomplished variations on well-known technologies but with the new 4Point he’s come up with something unique: an arm that combines the advantages of fixed gimbal and unipivot designs while appearing to avoiding the shortcomings of both.
Imagine a unipivot bearing: there’s a cup and a polished point. The point sits in the cup. VPI’s JMW Memorial arm series has the cup in the arm pivot housing; the point resides in the arm base. Graham’s Phantom inverts the two.
Kuzma’s ingenious design features a shelved horizontal bearing sleeve (a vertical post) that rotates upon a unipivot-like cup and polished point that allows the tonearm’s lateral movement. It doesn’t tip over though because enclosed within and attached to the bearing sleeve is a second point positioned at a 90 degree angle to the first that engages a polished surface on an internal post that is the actual bearing.
This arrangement keeps the external sleeve from moving in any unwanted direction, which is critical since there are two additional cups affixed to the aforementioned sleeve “shelf” that’s attached to the horizontal bearing sleeve.
A pair of precisely angled points attached to the lower surface of the removable tonearm assembly engages the angled cups affixed to the shelf, thus providing the arm’s vertical motion.
Thus you have four points, contacting four cups (three circular and one elongated) that allow the arm both vertical and lateral movement minus gimbaled bearing “chatter” and unipivot instability. Brilliant!
The Rest of the Design
The aforementioned bearing system is offset from the superbly engineered and machined locking vernier dial VTA tower adapted from Kuzma’s Airline tonearm.
This arrangement has a precedent of course, in Herb Papier’s 1980’s era Wheaton Tri-Planar (now just Tri-Planar), which also features a VTA adjustment tower and offset bearing.
A benefit of this system is that it allows rotation around the tower. Thus the 4Point’s 11” arm could be accommodated on the mounting platform Continuum designed to allow me to use the 9” Graham Phantom on the Continuum’s second arm mount.
The 4Point’s tapered two-piece aluminum arm tube is borrowed from earlier pivoted Kuzma arms. It permits easy and precise azimuth adjustment by loosening two screws, inserting an Allen key into a hole and turning. Lines on either side of the tube divide easily let you return to zero angle.
Also borrowed from the Airline is the rigid angled-construction head shell, but here it’s removable, thanks to a short, beefy hex shaped protrusion that fits securely in the arm’s corresponding hex opening and locks tightly via a grub screw located atop the arm. A tiny threaded hole lets you screw in a finger lift or not.
Try this system and you won’t lose a minute’s sleep worrying about a loss of rigidity, azimuth stability or adding an electrical break: the cartridge wire and clips protrude from an opening just behind the connector.
This arrangement makes swapping out cartridges fast and relatively inexpensive, particularly compared to the cost of swapping out whole arms (VPI) or tubes (Graham). Overhang is preset. All you have to do is reset previously established VTF, anti-skating, azimuth and VTA. This design makes that relatively easy.
While we’re at this end of the arm, note that there are two wires attached to each cartridge clip. At the other end of the arm there are two termination points: one is a pair of Eichmann RCA Bullet plugs at the end of a 1.4 meter run of high quality silver wire, and the other is a box terminating in a pair of Cardas RCA jacks. Thus you can choose to run direct out or via your favorite cable, or both (double the value of the desired load when connecting to two inputs of the same phono preamp).
The counterweight system is as ingenious as everything else about this arm. There are two threaded shafts. The larger one, located below the vertical pivot point is used to establish basic balance using a series of weights and damping washers, while the smaller upper one sets the actual VTF. Thus the majority of the mass can be located where you want it: close to the pivot point.
Anti-skating is set via the familiar thread, cam and weight mechanism attached to a platform that also holds the arm rest and cuing mechanism that is itself attached to the bearing platform. The 11” effective length means less anti-skating is needed than with a shorter arm.
In addition, Kuzma has provided for separate easily adjustable vertical and horizontal damping systems using the also familiar silicone fluid filled trough and paddle.
Other pertinent stats include: pivot to spindle distance of 264mm, spindle to VTA platform center distance of 212mm, and most importantly the arm’s effective mass is 13 grams. Oh, and the price: $6500.
Set Up And Use
Thanks to excellent instructions, photos, supplied tools and accessories, plus the removable tonearm, installing the 4Point was relatively easy (though on the Caliburn the specified pivot to spindle and spindle to base specs could not be met and a ‘workaround’ was required to achieve proper cartridge alignment).
I won’t go into the details here, other than to say it uses a 40mm post and collar type mount. Kuzma can supply collars compatible with virtually any mounting system, assuming your ‘table can accommodate the post’s depth and the assemblage’s more than 3.5 pound weight.
Set-up was straightforward for all parameters and equally important was the ease with which you could swap out head shells and re-establish them. The “feel” of this arm was superb. It had the stability of the best fixed-gimbaled arm and felt virtually frictionless. Lift the cuing arm and lower it and the stylus returns to the same groove. Lower the stylus into the lead-in groove and it never stumbles or slides into the first track.
Love at First Sight
I have to admit that when I first saw the 4Point a few years ago it was love at first sight. Its physical presence just about screams “stability” and “certainty” and so does the sound it doesn’t produce. I set up a 4Point in Stockholm last winter when I did turntable set-up seminars at an audio show there, but I never got to hear it.
Now that I’ve had it on the Continuum, I realize how unfair I was to the Brinkmann arm I recently reviewed. Of course the Brinkmann arm wasn’t as good as the 4Point. I’m not sure anything is, even the Continuum Cobra, though I’ll have a better idea in time for my next “Analog Corner.”
I also realized how fortuitous it was for Dr. Feickert to have the 4Point on the Blackbird! No wonder when I told him I planned to review the ‘table with the 4Point his reaction was something like “Oh boy!”
Rather than removing the Ortofon A90 from the Cobra, I decided to return the Lyra Titan i to service after a lengthy break. I had certain expectations since I knew its sound so well. High expectations were exceeded.
This arm has an immediacy, transparency and frequency response even-handedness that surpass that of any arm I’ve heard and that might include the Cobra but I’ve not yet swapped the A90 out for the Titan i. Why? What was coming from the 4Point/Titan i combo was simply too good to lose. It would have to wait until tomorrow and then the next day and then it was past deadline time. Sorry.
All of the Titan’s best qualities (dynamics, transparency and detail resolution) were revealed with unsurpassed intensity, while my one reservation, an apparent “tipped up” top end was nowhere to be heard. I’ve never heard the Titan i sound so tonally well-balanced.
One warm late evening was the first play of Brian Eno’s classic Another Green World. How many plays have the English and Japanese originals had since 1975? I can’t count but I enjoy this album as much now as then only it sounds much better now!
Through the 4Point, Percy Jones’s fretless bass achieved a tactile stickiness that was both delicate and depth charged as needed, which is what’s called for, but I’ve never heard it so cleanly and convincingly rendered. It was easy enough to go to the Cobra/A90 combo and I did go back and forth numerous times during the review period and these two combinations produced completely different results.
The Cobra/A90 was more polite and perhaps more nuanced and delicate but it was far less immediate and transparent and sounded as if a scrim had been placed between the music and the listener. The Titan i/ 4Point sounded more like tape and less like vinyl—or at least that’s what I kept telling myself.
I had another cartridge mounted on the second supplied headshell: the Miyajima Labs Kansui, which, put in the simplest way, is a higher compliance, higher resolution Shilabe. Swapping out cartridges produced a totally different sound, as you’d expect from a transducer change, but again, the immediacy and transparency transferred to the Kansui so that its character shone through unimpeded by the arm.
Running through a series of unfamiliar Quality Record Pressings test pressings of familiar music produced equally exalted results, particularly in terms of low-level resolution and fade to black quiet (wait until you hear Getz/Gilberto transferred at 45rpm from the original 3 track!). As familiar tracks faded out, there seemed to be more music before the final fade to black.
Swapping between the Cobra (no slouch!) and the 4Point confirmed the 4Point’s ability to stabilize solid 3 dimensional images and sail cleanly through difficult vocal sibilant passages across the entire record surface.
Perhaps the music on Oscar Peterson’s We Get Requests isn’t the greatest (covers of “People,” “Days of Wine and Roses” and other ‘60s pop) but the recording is. The 45rpm Analogue Productions test pressing demonstrated the 4Point/Titan i’s ability to achieve produce timbral, textural and image solidity plus transparency on Peterson’s piano that the Cobra/A90 did not. The latter’s version was very, very good but the individual notes did not hold up with the same level of purity and cohesiveness. The 4Point/Titan i produced a physical certainty and solidity piano stroke after piano stroke that the Cobra/A90 seemingly did not.
I’d been repeatedly playing “Teeter Totter” from the Music Matters 45rpm Blue Note reissue of Joe Henderson’s Our Thing (MMBST-84152) and though it’s a good Rudy Van Gelder recording, Andrew Hill’s piano has the characteristic Rudy piano mud, but the 4Point cut through and cleared up a remarkable amount of muck leaving a gleaming keyboard. The Cobra/A90 was good but not as coherent, nor as immediate, nor as three dimensional. Until I’d made these comparisons I didn’t think it could get any better than the Cobra. Now I’m not sure.
From the bottom end clarity and weight, to the image solidity and three dimensionality, to the seemingly neutral tonal balance and remarkable transparency, the Kuzma 4Point seemed to surpass the Cobra’s excellence in all of these parameters.
What accounts for this performance? The damping the Cobra lacks? That may be part of it but I think it’s more a result of the 4Point’s stability coupled with the tightness of the chatter-free bearing.
I plan on making 96/24 recordings of the 4Point/Titan with and without damping and the Cobra/A90 and then swap out cartridges and repeat. So please stay tuned.
While Franc Kuzma’s concept was unique and incredibly well thought out, a great idea can only take you so far: the execution counts as much if not more. Clearly Mr. Kuzma has executed.
As I wrote near the beginning, bearing quality has a profound impact on sonics and I’m not sure there’s a better bearing system than what Franc Kuzma has designed for the 4 Point.
As I also wrote near the beginning that when you read about some “breakthrough” technology don’t believe the hype if it doesn’t include the inevitable downsides of that “breakthrough” technology.
I can’t figure out what the downsides might be here. Kuzma hasn’t come up with any new “technology.” He’s come up with a new and ingenious use of well-known technologies, the up and downsides of which are well known and which he’s seemingly avoided!
I think the Kuzma 4Point is a better arm than the Kuzma Airline. I think it avoids a brightness I couldn’t tame in the Airline and that listeners at CES picked out immediately on CD-Rs I played recorded from it in various rooms. Was that caused by an oscillation at the annular gap and the pressured air returned to ambient room pressure? I have no idea.
I value that 4Point’s tonal correctness more than I do whatever audible (or in my book mostly inaudible) tracking error distortions are caused by pivoted playback.
What I do know is that while I am hesitant to call anything “the best,” unless the cartridge swap described above changes things, I can definitely say that the 4Point produced the best performance from the Lyra Titan i that I have ever heard from it here: it tracked the best, its tonal balance was best, its imaging was best, its cleanliness on vocal sibilants was remarkable (and best), it’s bass performance was as deep, fast and nimble as I’ve ever heard it, and its image solidity and soundstaging in general were the best I’ve heard.
The sound the 4Point produced had an immediacy, continuity, transparency, linearity and freedom from mechanical artifice that until now I thought you could only get from reel to reel tape. Oh, I might have said that before and others have, but this time I mean it dammit!
Add to that mechanical robustness, ease of cartridge swapping, set-up ease and an effective mass that should allow it to be used even with a high compliance cartridge such as Shure’s V15VxMR (though the resonant frequencies will be on the margins of acceptability) and you have one incredible tonearm! I’m in love.