Strange Tonearm Tweak. Long


As you all know, I am a little different. I like to read and study stuff like tonearm technology. I noticed that some of the better unipivot designs have employed "outrigger" style outboard weighting systems on their arms, that work like a tightrope-walker's balance pole. This not only balances azimuth, but also gives the arm better stability to lateral deflections from the cartridge suspension, so the arm is not moved when the stylus is pushed laterally by the groove information. I began to think on this, and I wondered why no gimbal-bearing arm makers are doing this. Surely since the vertical plane rides on a vertical axis bearing, there is still some chance for the arm to be laterally deflected by the stylus, when the stylus should be doing all of the moving, not the arm. I think that this is why they use heavy arms, but a heavy arm in the vertical movement plane is not good for tracking. A heavy arm in the horizontal movement plane is good for resisting sideways deflection that would impair pickup function.

So I decided to try increasing the mass of my tonearm in the lateral plane, while keeping it light in the vertical plane, by the use of "outrigger" weights, just like a unipivot does.

I bought lead fishing weights that looked like long rifle bullets(just the lead part) They were about an inch long and about 3/8" diameter, and weighed 12 grams each. I drilled into the bases about 1/4" and press-fitted them onto the nuts that hold the arm into the bearing yoke, so they stuck out straight sideways, like sideways spikes. This put the weight out pretty far to the sides as outriggers, and kept the weight centered exactly around the bearing pivot axis so it did not increase the vertical mass significantly, but it did very slightly. It did not influence the tracking force at all.

So now the arm had outrigger stabilizers on it in the horizontal plane of motion.

I put on a record and sat down to listen. Let me tell you, fellas, this was a mind blower. I have never heard this much information come out of a cartridge before. I heard sounds on records that I had listened to for 30 years, and never knew those sounds were on the record! And I have had some pretty good analog gear in my time. And what I didn't own, I heard at the audio store I worked at. This is the most astounding mod I have ever heard on a tonearm. And it cost me $1.49 for the fishing weights, and I got 3 extras.

The only slightly negative thing about it, is that it increases the anti-skating force, so you have to cut that back a little, and if you have some marginal scratches that might skip, they are more likely to skip with this mod, due to the resistance to sideways movement provided by the outriggers. I had this happen once last night, but I didn't consider it a problem.

But the increase in dynamics, and detail and overall sound quality is astronomical. It blew me away.

I have a DL103, which is a very stiff cartridge, and it may be that this is not needed for a higher compliance cart. But, I think that it would be good for anything that is medium or lower in compliance.

The key to it, is that it only increases the resistance to sideways movement, without interfering with the effective mass of the arm, or the vertical swing movement that needs to stay light to track warps. I played some warped records with this mod, and they played just as well as without the mod, except they sounded better.

I have a pretty good analog setup now, but I can say without reservation, that this mod made my rig sound better than any analog rig that I have ever heard in my life. I have never heard a Rockport.

Stabilizing the arm against unwanted lateral deflection increases the information retrieval and dynamics by a very large percentage. If your arm is not set up like a Rega style arm, then you can glue a 1 ounce long rod across the top of the bearing housing(sideways) like a tightrope-walker's balance pole. Use lead if you can, it won't ring. You don't have to do any permanent changes to your arm that might wreck its resale value to try this out. If it has anywhere near the effect on your system as it had on mine, you won't be taking it off.

It may come close to the movement of your cueing lever, so make sure you have clearance to use it. Mine was close, and I have to come in from the side now to use the lever, at the end of a record. That is fine with me! This was a major, major improvement in the sound of my rig. It is staying permanently. As in "forever".

If you are a little tweak-oriented, and not afraid to do stuff like this. You should try it. It will knock you over.
twl
have an RB300 mounted on a Townshend Rock Mk. III. This turntable incorporates a damping trough at the cartridge. The trough is filled with a viscous silicone solution. An outrigger assembly is mounted at the headshell that has a paddle that runs through the viscous solution . The RB300 came from Townshend. It came with the tungsten CW w/ an additional weight epoxied to it to offset the added mass of the outrigger. The diameter of the hole on the additional weight is larger than the shaft. Its weight is being supported by the tungsten cw.

I am using the latest Shelter 501.

I applied the TWL mod last night with great anticipation only to find VERY minor appreciable effect. Perhaps a VERY SMALL increase in bass definition and weight.

I am wondering if the trough of the Townshend is providing similar stability to that of the mod?

Any thoughts would be appreciated.
mctigues,

Have you tried listening without the silicone dampening engaged? Try this without and with the HIFI Mod. That would probably be a good test of your question.

Personally, I have never liked the effect of silicone dampening (except on unipivots where the silicone sits directly around the bearing). On gimballed arms like your Silver and my TriPlanar, I much prefer the sound with no silicone in the trough at all. YMMV of course...

Doug
Thought I'd drop by.

My Jelco arm (think MMT, Audioquest, Graham Robin)doesn't have the capability of pressure-fitted weights like the Rega. But on each side of the bearing housing I thought there might be room on the sides for something, small flat spots where bearing adjustment "screws" are located, so I thought some more for something that I could do fast. The arm is mounted to a restored Russco Mk V, with a DL103 cartridge.

A few minutes later I glued six quarters into two groups of three, face to face, with a hot glue gun. Used the same hot glue to attach the quarters to the spots I referenced above. Totally reversible as the glue stays a bit soft after curing and peels off of metal with just a bit of effort.

Shazam! The effect seems exactly as described in your initial post from five years ago. I may engineer something a little prettier in the future, but the 16.5 grams or so on each side (each quarter is 5.5 grams)works very well with this arm (and presumably variants of it like those mentioned above). I don't know if the greater weight (compared to the fishing weights) compensates for their shorter lateral reach (compared to the fishing weights), but that was my thought when gluing three quarters together instead of two.

If anyone is curious I uploaded an image here--http://new.photos.yahoo.com/deanmanjames2003/album/576460762310128890

Comments, suggestions welcome!

Jim
Has anyone tried and listened to differences. I would prefer to use tungsten bullet weights instead of lead due to toxity of the latter.

Any sound difference?

Roger
Hi guys.
It's been a long time, and I've been away from the site.

I'm happy that some of you are finding out what this mod can bring to your music.

Regarding the Townshend with the silicone damping trough, yes the damping is having a similar effect but in a different way. That is probably why the effect of the mod wasn't as noticeable in that case. Being that the silicone trough is up at the headshell area on that TT, the stabilizing effects will be nearly immediate in that case, but not quite immediate. That is likely why the TWL mod was still giving some benefit, but not as much as usual.

I'm still getting a chuckle that after all these years, people are still finding out about this thing, and getting amazed by it.
It's a very simple application of basic tonearm design, that seems to have eluded the tonearm manufacturers even to this day.
Too bad I can't get rich off this idea. But, if people can enjoy better sound for next to nothing expended, I guess that is reward enough for me.

And yes, the tungsten weights or other types of weights will work just fine.
...that purposely increased lateral mass over vertical:
http://www.kabrna.com/hifi/orion_tonearm.htm

Still a great idea, though, to separate the two resonance frequencies, and lower the combined peak.
Oops; the last subject line was supposed to be something about an '80s-era arm...
Well this is my first post on this forum, made plenty on others though, I registered mainly because this thread struck a chord. I have long felt that the concept of damping in the horizontal plane is sound and some time back I tried a slightly similar idea.

In my case along with a list of mods too long to go over I added a round weight over the top of the tone arm at the centre pivot, in my TT this works as there is a yoke that comes up and over the arm, so the weight sits on top of that and is actually an old video head. If you go to my webpage here
http://homepage.mac.com/braddles/Menu2.html
You will see what I mean.

Anyhow I was attampting to do 2 things, one add more mass so as to make it more difficult for the arm to deflect in the horizontal plane in response to unwanted tracking movements and secondly to kill bearing chatter in what is a pretty rudimentary arm.

Net result was that the sound was much improved, the bass much stronger and tighter and highs sweeter I would say due to the lower chatter levels. It may just be too that one of the reasons for the much improved sound others are experiencing with this type of mod is also reduced chatter as the bearing would be more stable in all directions when playing and I would say using the outrigger idea on this thread would be superior to mine in doing that.

The mod talked about in this forum takes it to another level I would say and will try it.

I feel there would be an optimum weight that would work and beyond that the damping too great so it would need careful assessing of just how much.

This concept though is also related in essence to the idea of longhorn mods on carts, which is something I have found very effective on stiffish carts. If you have a look on my web page you will see a set of pics for my "waveclone 01" cart which I built up from a very cheap cart, it has an integrated longhorn mod. (note that this is quite a bit different to the usual implementation).

The tracking with this cart is marvellously secure and it sounds way way better than it really should considering it started out as a $10.00 cart, so in I think stabilization at either end of the arm can be a good thing and they can probably work in very nicely with one another on stiff cart in basic old arms.
I'm puzzled now. The additional lateral moment of inertia is really quite low on this tweak, so that can't be all the difference. Or can it?

On the other hand, Twl has mentioned Coulombic friction, at which point it occurs to me the tweak should then work better on the OL Silver, with its exposed pivot, than on the unmolested RB250. Reasoning being, on the OL Silver the weights will damp out both the vertical and horizontal bearings, whereas on the RB250 without removing bearing covers the weights will only damp out the horizontal bearings.

On the other other hand, Zero_one's tweak clearly only damps out the horizontal bearings (and how!) anyway...

Unfortunately I can only speculate at this point because I have an arm, but no table yet...

But all very interesting...
IME with the HIFI mod on an OL Silver, the sonic improvements were entirely consistent with an increase in lateral moment of inertia. Bigger dynamics, stronger, tighter bass, faster transient response, etc.

I do not recall much if any improvement in areas that I'd attribute to improved resonance damping. No greatly lowered noise floor, no big reduction in overly resonant notes, etc. I DID hear those things when I adopted Twl's suspended counterweight, which pretty much entirely decouples the c/w from the arm. That's another story though, and it's not easily used.

Read through this whole thread if you dare. There's a lot of interesting material and experiences here. Taught me everything I know! Thanks again for the nth time to Twl for forging a path so many followed to better sound.
I've actually read through all of this thread, and have gotten some very interesting ideas, but have my doubts, too, when it comes to the actual numbers. Such as, 24g at 2in is only 1g at the headshell. Perhaps that's enough to be meaningful? Not sure... Itching to try all this...
anyone have a picture of this tweak? call me dense but I think I need to visualize it before I "get it".
Your idea is not really new. Take a look at the VPI arm. There are 2 outrigger weights that are not there for azimuth adjustment..this is done by rotating a dropped counterweight. In truth the problem with this arm is that it is quite diffucult to set up since the rear weight effects azimuth, VTF, which also has an effect on VTA. After lots of careful adjustments, the arm is very good indeed I think the autrigger weights are there to increase mass in the horizontal plane as you suggest.
When I had the Rega arm, I noticed that unsing the spring to exert downward force for the cartridge pressure caused the spring to vibrate and cloud the sound on some frequencies. I simply didn't use it, set it to zero, and used the Expressimo weight forward of neutral balance. I used a Sure scale to measure the 1.8 grams I needed for the cartridge
Anyone with a rega based arm should try this tweak. It costs about $1.50 and takes about 30 minutes to do assuming you have an electric drill and the right size bit and some mechanical ability. I had been struggling for about 3 months trying to get my vinyl to sound as good as I thought it could. I read everything used every free online protractor but still wasn't satisfied with the quality of the music I was hearing. I implemented TWL's tweak 3 days ago and the improvement was amazing, everything finally snapped into place, even the inner grove distortion I have been struggling with is almost completely gone. With out a doubt the best most cost effective tweak I have ever used. Thanks TWL
Folks interested in this tweak may find value and similarity in perusing the Audio Basics article from around 1985 by Frank Van Alstine for his Grado Longhorn stabilizer. I have used it for years on Grados and then abandoned it when I bought a Platinum. Then a few years ago when I got a Shelter 501, I decided to trial fit one and am sold on it again.