SL1200 upgrade tonearm or replace cartridge?

If you check out Jeff Dorgay's article in ToneAudio's Issue 22, he replaces the internal power supply with an aftermarket one, and the mounts an SME 309 and reports the results. An excerpt:

...if you want to push the boundaries of what you can achieve for an investment of $2,000 in a turntable. I’ve had the opportunity to listen to a lot of turntables in the $2,000 - $3,000 range from Rega, VPI, Pro-Ject, Music Hall, etc., and for my money, this one is the one to beat.....

I read somewhere, and maybe someone else can speak more definitively, that the servo circuit within the SL motor is constantly hunting for the proper rpm. While looking at the strobe it appears to be visually stable but the motor is continuously compensating.

I believe that's a widespread myth, and am pretty sure I even read it in Stereophile once. However, I've never seen any evidence that it's true, such as measured speed or pitch variations. Some people feel that the SL12x0 series has an upper midrange glare or resonance, and since the servo operates at 3500 Hz, some audio journalists *theorized* that the servo frequency caused the glare, but then passed it on as fact.

I've read on the KABUSA.com site that this is false, and he has the 'scope captures to prove it. In my personal experience with my SL1210 M5G (and AT150MLX for that matter), I set about to neutralize all resonances and vibration I could find. There *was* a persistent subtle glare in the upper midrange; when I flicked the tonearm with my fingernail it seemed to ring at the same pitch. The tonearm is an undamped aluminum tube, which by its nature is very resonant. I wrapped the tonearm in inexpensive lightweight Teflon pipe thread tape and the resonant peak disappeared.

Most of the complaints about the Technics lack of clarity can be readily and cheaply addressed with damping and vibration control. I upgraded the headshell to a pretty inert LPGear ZuPreme, installed KAB's fluid damper, wrapped the tonearm, swapped in a sorbothane platter mat, replaced the stock feet with brass cones situated on inverted Vibrapod cones sitting on Vibrapod isolators sitting on a 3.5" thick heavy butcher block cutting board isolated by some silicone gel pads. It sounds convoluted but cosmetically it actually looks OK and every tweak I mentioned incrementally improved clarity, musicality, lowered noise floor, improved dynamics, etc.

Yes, the Technics has some resonant peaks and some clarity problems out of the box, but they have nothing to do with the servo frequency and are inexpensively neutralized.

02-07-13: Zenblaster
Don't forget that all the damping and wrapping come at a price. These are fixes to tame resonant frequencies, to move towards a more musical and less analytical presentation. I would love to put my 10' vpi tonearm from a Traveler on my KAB 1200 deck, I just can't seen to get past this gastly Technics tonearm. It just seems to take some of the life out of the music.

I don't get what you're trying to say. All the damping tweaks I mentioned improved the sound. It didn't just reduce midrange glare, it improved inner detail, linearity, microdynamics and macrodynamics. The sum total is that with these tweaks the music is more lifelike and involving.

The only place I encountered overdamping is if you put too much silicone goo in the KAB damping trough--then the dynamics flatten out and the music turns lifeless. This is the universal symptom of overdamping. This is easily fixed by filling the damping trough only one-third full.

Each tweak fixed something different. The record grip damps spindle and surface noise. The mat damps platter ringing; the tonearm wrap damps tonearm ringing. The brass cones/vibrapod/cutting board drain extraneous vibrations out of the chassis; the gel pads under the cutting board isolate the turntable from room vibrations. Each tweak addresses a different set of vibrations and resonances.

As for "coming at a price," it was $150 for the KAB trough, $10 for a used sorbothane mat, $50 for the headshell, $20 for brass cones, $56 for Vibrapods, $25 for a rubber record grip, $89 for a big, heavy cutting board and $30 for two computer keyboard gel wrist pads. The results were improved musical reproduction in every way with no subtractions.

03-03-13: Dave_72
How would you go about mounting an SME tonearm?

Sound Hi-Fi of England, purveyor of many SL1200 mods and aftermarket parts including an SME arm board.

Tone Audio Issue 22, which includes a piece by the editor about mounting a SME arm with the Sound Hi-Fi arm board.

Zenblaster: I agree with you. I've read enough testimonials of good tonearm swaps to agree with you that at some point you're throwing good money after bad on the SL12x0 stock tonearm. Technics must have realized this too, as they originally also offered the SL120 with an armboard drilled for a SME 3009.

In my case I added the KAB trough because I had just bought the turntable and had $150 to damp the supplied tonearm, but not $700-2000 to replace it. After that, I have less than a nickel's worth of pipe thread tape and a reasonably priced aftermarket headshell. After that the tweaks are things the Technics would need anyway for vibration and resonance control, and they don't add up to a lot of money.

At this point the only thing left is to upgrade the tonearm to get that more holographic soundstage and deeper inner detail. When the time comes I'll probably get an SME arm board from Sound Hi-Fi of England and search for a reasonably priced (?) used SME 309 like Jeff Dorgay (of Tone Audio) did.

Nick_sr: I think the improvement realized with the tonearm wrap is system-dependent. I have an Audio Technical AT150MLX which has a reputation for being forward and bright. Wrapping the tonearm quelled that bright spot. I suspect with a mellower signal chain or a cartridge with a kinder upper midrange, the tonearm wrap wouldn't do as much. You *do* have to also wrap the knurled collar that attaches the headshell to the arm to get the full benefit. That collar rings at least as much as the rest of the tonearm as a very resonant ping.

02-14-13: Vicdamone
...
After reading your tweaks I think I'm going to give them a shot. Thank you very much.

Here is a picture of my SL1210 M5G and the tweaks I've made.

o The tonearm has the KAB fluid damper and is wrapped in Teflon pipe thread tape
o The headshell is an LPGear ZuPreme.
o The platter has an Oracle Groove Isolator sorbothane mat. I'm sure any good damping mat would work.
o The standard feet have been replaced with a Dayton speaker spike set. Available in various finishes, the black chrome is a great match with the Technics. At $29.95 they're a stone cold bargain for a set of four solid brass cones. The supplied threads are an exact fit for the threaded sleeves on the underside of the Technics. I unscrewed and removed the cones' adjustable tips to truncate the cones and create a concave bottom.
o The concave bottoms fit perfectly on the steel balls of the Vibrapod Cones, which then rest atop Vibrapod #2 Isolators. if you want to simplify, just unscrew the stock Technics feet and rest the threaded sleeves on the balls of the Vibrapod cones. This alone has a significant effect on lowering the noise floor and adding inner detail.
o I sit this whole mess on top of a 3-1/2" thick maple butcher block cutting board. I used to use an inexpensive 1-1/2" thick cutting board from Ikea. Moving up to this massive board ($100 or less from overstock.com) made a quite noticeable difference which my wife described immediately after the change.
Under the cutting board is a pair of computer keyboard wrist pads made of silicon gel.

Yes, it's a bit convoluted, but it actually looks pretty nice and the whole stack of cones, pads, and cutting board total about $200, less than a typical retail vibration isolation platform and more versatile. This enables me to take advantage of the Technics' outstanding torque and speed accuracy while minimizing its weaknesses in vibration control and isolation.

03-04-13: Dave_72
Oh ok, thanks for that. Interesting stuff. However, the stock tonearm on the 1210M5G doesn't ring or send subsonic signals through my speakers when tapped. And the 'table doesn't howl at high volumes. Maybe it's true that this is a better, more heavy duty model over a stock 1200 MK. 2.

My rig is also an SL1210 M5G with an AT150 MLX cartridge. However, every tweak I added as shown in the picture of my turntable produced an audible improvement in frequency linearity, dynamics, clarity, or lowered noise floor. When I tapped the tonearm I didn't get *subsonic* ringing, but a marked resonance where midrange hands off to treble. Still, much of this tweaking may be system-dependent and your TT could be a more natural match for your rack, wiring, electronics, speakers, component layout, and room.

The tonearm of the SL1210 M5G is different from the other 1200 series in a couple of ways--it's wired with oxygen-free copper and there is a set screw near the pivot for adjusting for DJ scratching. Other than that it's the same as the others--same weight, same shape, same bearings, no physical damping of the tube.

03-05-13: Dave_72
Of course there is better, but I have a hard time justifying the prices when the Technics does a lot for me sound wise.

I agree. In the belt drive world, turntables that have the speed accuracy of the Technics cost $2500 or more. However, for very few dollars you can add vibration control tweaks to the SL12x0 series that lower the noise floor and improve dynamics, clarity, detail, smoothness and linearity.

Aside from KABUSA's $150 tonearm damper, many of the other tweaks are relatively inexpensive. Using Teflon pipe thread tape, you can wrap the tonearm for about 15 cents and get a smoother midrange.

Another very cost-effective improvement is to toss the stock Technics feet and place the turntable on a set of Vibrapod Cones, setting the turntable's female thread sockets (where the feet screwed in) directly on top of the metal balls of the Vibrapod Cones. For another improvement, set the Vibrapod Cones on top of matching (and weight-matched) Vibrapod Isolators. This entire tweak costs $56 and does wonders for inner detail and clarity. Vibrapod has a 30-day return period so your experimentation is protected.

You'll also notice a drop in record surface noise with KAB's Record Grip.

Even with these tweaks the SL1210M5G is a stone cold bargain. It enables you to retain the SL1210's strengths while reducing or eliminating many of its weaknesses.