Oh, and I'm gonna try this tweak on a Rega/OL arm with the Denon, as soon as I decided upon and buy the arm.
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.
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.
269 responses Add your response
Thanks, joe I was just needing a little reassurance. That's the company that I was looking at, only 5 days, AUH Yeah! When my Grado gets off auction tommorow I will have to order one, unless Doug sends that Shelter, hint,;)-~. Hey TWL don't let the nay-sayers get you down, just set up your force fields with positive energy and healing thoughts. They can't affect you if you don't let them. Remember it's all a reflection of themselves, that they are projecting, don't take it on. AAAUUUUUUUUUUMMMM:) |
I'm sad to have to report that we have officially moved on. The TriPlanar doesn't quite match the HIFI-modded Silver for leading edge transients, as I noted above, but it excels in all other parameters. That's what you'd expect for 4x the MSRP of course, so that isn't exactly news. What is news, and very good news too, is that a well-respected member of our little community has bought the Silver. It should enjoy an active life in a loving and appreciative home rather than doddering off into idleness in my attic. Even better, I believe it's headed off to college! Not only is the Silver rugged enough to survive that environment, I have every confidence it will help open the ears of another generation of music lovers to the musical truths of analog playback. Party on! :-) This was our first high end arm. Thanks to Twl we started off right, with solidly implemented analog playback at a sensible price. A modded Silver is precisely on the cusp of the price/performance curve, exactly what we were seeking, exactly what Twl described. Paired with the right cartridge it represents enormous value for the money. IME that is as true today as the day this thread began. At least we kept pictures. We will always have fond memories of those Silver days. |
Hi TWL, thanks a lot for this great thread and information sharing. I just learned of your tweak. Owing a 250, with expressimo cw, and a cart with a much higher compliance 25 µm/mN (so 5 times DL103's one), I was thinking if, in your opinion, a linear model might be common sense in order to find weight lateral size. In this case I immediately thougt of 12/5, i.e. about 2.4grams/each "stabilizer". Is it too simplicistic (apart from try and listen :-) )? Thanks a lot, Stefano |
Stefano, thanks for your question, and I'm glad you enjoyed the thread. In my opinion, a cartridge with a compliance of 25 is not going to move the RB250 laterally. The standard effective mass of the RB250 should be sufficient to laterally stabilize that cartridge. I don't think that adding any additional horizontal mass would be productive in this case, and there is a possibility of causing a mismatch in mass/resonance if you do add horizontal mass to the tonearm with a high compliance cartridge, such as you have. |
In a purely aesthetic vein, I was in the store other day to find weights for my OL Silver. In the store I visited, there was literally an array of lead and brass weights in a variety of colors. Black, which matched my arm perfectly, gold, silver, tortiose shell, neon colors. Some looked VERY cool. Guess the fish can tell a difference too! I JUST set up the arm the other day with a Denon 103R. Tried it sans weights first and things were pretty damn good. Then, last night, I took two 1/2 oz. weights and drilled out the centers a bit and matched their weights on a digital scale until each was 11.75gr. Installed and spun again. OK, this invention is probably the biggest bang for the buck (well, actually cents) in the history of audio. The additional detail was not to be believed unless heard and the tightening of the bass was kinda scary. So much so that I wondered if it could actually be attributed to such a seemingly meager mod. But, I am not willing to take them back off to find out. Bravo, Tom! Good work! |
FWIW, I invented this mod because I cannot play in the upper stratosphere of high priced tonearms and other equipment. I have a budget, and so I only tried to make the most of what I could afford to buy. I have also tried to do stuff like this with my other equipment, so that I could have as close to "top end" sound as possible, given my low budget for purchasing. Necessity is "the mother of invention". I would urge anyone who likes this HiFi mod, to experiment with Lowther single-driver speaker systems and low-power SET amps. That combination makes an exceedingly enjoyable result at the back-end of the signal chain too. The mods that I've made to my Lowther EX4 equipped Voigt pipe cabinets makes a significant improvement to that design too. And the cone treatment that I used is very effective in virtually eliminating what is left of the "Lowther shout" from the current version of the Lowther speaker drivers. My cabinets only had one very noticeable flaw(within their intended spectrum range), which was a "hollow sounding" coloration in the lower mid-bass, from some cabinet resonance effects. This was totally eliminated when I placed the Sistrum SP-004 platforms under the speakers. It was miraculous in eliminating this resonance from the cabinets, and was one of the major factors in my eventually seeking employment with Starsound. A well-tuned Voigt Pipe with Lowther drivers, using my "swinging doors" baffle mod, and placed on Sistrum SP-004 platforms, is one of the most musically enjoyable speakers that could be had for the money spent. Of course, my custom David Berning 45 SET-ZOTL is a very nice way to drive them, but any good quality SET of under 8 watts(with good output transformers) would be a nice pairing with these speakers. I am transfixed by the sound quality every time I play my system. It always puts a smile on my face, and sometimes I even have to get up and dance in the room. I only say this, because most people have liked my tonearm mod, and I want to share some of the other things in my system that have given me equal improvement to my listening pleasure. I'm not going to make any speakers for sale, but the plans are on the internet, and anyone can email me for info about the mods, or proper tuning procedures for the Voigt Pipes, or the cone treatment. Basically, the mods relate to eliminating the baffle-step losses associated with narrow-faced speaker cabinets, without resorting to electronic filtering, and the cone treatment stiffens the cone without adding mass which would slow down the speed. This changes the cone-breakup mode which coincides with the transition from main cone to whizzer cone in the critical upper midrange which is generally called "Lowther shout". It solves it. The SP-004 platforms are required to eliminate the cabinet resonance in the mid-bass region that happens because the lower half of the Voigt Pipes must be hollow. |
Ciao Tom, thanks a lot for your kind answer! Meanwhile, yesterday I tried with a small amount of tack and used 2 small bits of an unknown metal (each about 2,3 gr.). I must say that, at least, I didn't hear any drawbacks with my Goldring 1042. Indeed, I seem I have listened to smoother and more extended highs. Bass are - quite - good (as before). BTW, I'm going to some more DIY on RB250 (rewiring, remove lift, remove some paint at cartridge end), thanks for your suggestion! Ciao, Stefano |
David, I like the hanging counterweight a bit better than either the stock OL counterweight or the Expressimo Heavyweight. Everything seems to be a bit more open and less "confined". A bit more "liquid". It's not a really big difference, like the HiFi mod is, but is provides a little more performance from the package. It is only suitable on the OL Silver(or Rega variants) because the Encounter and Illustrious have the different type of anti-skating mechanism and base platform differences which would interfere with the presence of the hanging counterweight. I tried to implement it on the Encounter when I had it here for audition, but it was not applicable to the Encounter. |
Ciao Tom, thanks a lot, I already got an Expressimo stub and cw which satisfied me a lot! The idea behind your strange tweak intrigued me and I tried to estimate the math relationship between cartridge lateral compliance and additional rotational inertia given by your extra weights, in order to get a general solution... I'll try to study it in a physical mood... Ciao, Stefano |
Stefano, I don't have any photos. But I can explain. First, we must look at the way that I have the hanging counterweight slung under the tonearm. I use a length of Spectra fishing line, which is high-tensile non-stretch line. Then I hang the long shaft-shaped counterweight on 2 points(each end of the weight) and sling the line over the tonearm. This gives the mass effect in the lateral plane as well as horizontal. Then we must look at what we are trying to accomplish. First, it is understood that the counterweight mass should be as near the plane of the record as possible, for best tracking ability. The standard Rega counterweight does nothing in this regard, as the mass is all centered at the same plane as the tonearm. The Expressimo Heavyweight does lower the plane of the mass(by making the hole off-set) and has more of the mass below the tonearm, for better tracking. But the off-set hole causes the tonearm to shift tracking force when the arm rides up over a warp, because the mass distribution is unequal in the vertical plane, and when the arm rides up over a warp, the bulk of the mass of the Heavyweight actually moves foward around its rotational circle(which is different than the rotational circle of the tonearm). Additionally, the mass that is below the tonearm on the heavyweight only comprises a relatively small shift in the center of gravity of the counterweight mass(although it is audible improvement). It has a price, and that is the counterweight mass is no longer symmetrical when the arm is in vertical motion. This is the reason why Mark Baker is not using an off-set counterweight on his OL tonearms. Now, to make the full step to making ALL the mass of the counterweight at the same plane as the record, for best results, requires some different implementations. First, the mass must be equally distributed in all planes for symmetrical operation during movement of the tonearm during play. Second, it must provide the normal counterweight functions, which are balancing the arm, providing tracking force, and providing a certain amount of lateral stabilization. By hanging a shaft-shaped counterweight cross-wise under the arm end-stub, we can hang it like a child's playground swing, with the string slung over the end stub. By slinging the string over the end-stub, we have lateral stabilization as well as vertical, because the string wraps over the end-stub and has enough contact around the diameter to provide the mass effect laterally on the tonearm. The non-stretch string(Spectra fishing line) provides a solid tie to the counterweight on each end, thus effectively making the counterweight operate as a solid tie to the tonearm in the lateral and horizontal planes. However, the counterweight will still "yaw" in the "z plane"(fore and aft), so that the counterweight mass will remain plumb under the end-stub of the tonearm during rise and fall during warp play, and still retain the correct tracking force, and still maintain the correct position of center of gravity down near the plane of the record. The result is that ALL the mass of the counterweight is now moved to the correct position at the same level as the record, not just some of it. Also, the mass remains efffectively constant during vertical movement of the arm. Third, and possibly most important, the mass is effectively mechanically decoupled from the end-stub, which results in a free-er sound, less encumbered by high mass and addtional parts, so its natural resonant properties may occur with less reflection and harmonic effects due to 2 different masses being coupled together by a screw at a random point on the end-stub. The string has a natural resonance damping effect by simply vibrating, and the ends of the string are placed into the lead mass of the counterweight shaft, which has sufficient mass to absorb and damp the vibrations. Regarding your question about horizontal stabilization effects, the hanging counterweight is coupled horizontally well enough to provide this stabilization function. Remember, that the purpose of horizontal stabilization in the tonearm is to prevent it from being moved by the compliance of the cartridge during play. If it gets into motion from these forces, we have already failed to stabilize it. It is the "static moment of inertia" which we are dealing with here. The amount of force needed to start this body into motion. If the static moment is higher than the cartridge(on the arm) can apply, then the arm will be stable, and not be moved into unwanted motion by the forces applied by the cartridge, and the performance will increase, because all the stylus movements will then be generated into electrical signal, and not lost in unwanted arm movement. I wish to mention however, that this is a small increase in performance, not on the level of the HiFi mod. It will add to the sonic performance of the arm in an amount of a few percent. The liquidity is better, and the sound is more open. I have found that just slinging the string over the arm, results in a "crawling" effect of the string on the end-stub. This causes change in tracking force, and is unacceptable. I then put a rubber O-ring on the end stub, to act as a "stop" for the string, so that the string cannot crawl toward the back of the end-stub, which is where it wants to go. It is not needed to put an O-ring in front of the string, because the string only wants to crawl backward. It also acts as a guide for replacement of the counterweight, if you ever want to remove it for cleaning or anything. You just put the string back on the end-stub, just contacting the front of the O-ring, and you have your pre-set tracking force established. Setting the tracking force with the O-ring is place the first time, is a bit finicky, and can be tedious. But once it is placed, the position is set, until you move the O-ring. If you want to make small VTF adjustments, it is advisable to use Doug's VTF on the fly modification, since small VTF changes with the O-ring is a pain in the ass. |
I've used the C/W Twl just described on my O/L Silver, based on his description earlier on this thead. I can confirm all the sonic changes and benefits he described. One more tip: adjust the mass of the weight so you can hang the thing as close to the pivot as practical for proper cartridge balancing and VTF. This should improve warp tracking and reduce the weight's tendency to swing. I would not necessarily want to use a free hanging C/W on a floaty, suspended TT. On a solid, nonsuspended one it's a nice upgrade. Not as big as the HIFI Mod, like Twl said, but it really does reduce armtube resonance reflections. This results in less overhang on virtually all notes, for a cleaner and tighter presentation. Recommended if you can deal with a bit of fiddliness. The O-ring is essential, the C/W would be insufferable without it. |
OK Tom, without going into every detail to the Nth degree, here's what's on my mind now: First of all, I'm not sure I fully understand why or if it's necessarily desirable to decouple the counterweight. Or to go for lowest mass in general. But if we assume that these are desirable goals, then why not get completely rid of the coupled mass of the counterweight? Hanging the weight off the end of the tonearm's rear extension seems like it would invite a swinging motion in response to energy inputs at the stylus, since the string can't perfectly decouple the weight. Additionally, the weight would be free to oscillate in response to spurious energy inputs to the plith as a whole, such as from loud bass notes or footfalls. Today's post is a simpler design then in the post I deleted. End the tonearm at the pivot point, with no extension continuing behind it. Take a cue from the design of a conventional suspended-weight anti-skating arrangement. Hang a weight from a string, run it over a hanger positioned above the tonearm, and attach the string to the tonearm (moveable to fine-adjust VTF). The force of gravity pulling down on the weight now pulls up on the tonearm, offsetting the force of gravity pulling down on the tonearm/cartridge, minus the desired tracking force. The hanger is mounted on the horizontal bearing housing, in order that there will be no lateral relative motion between the hanger and the tonearm. The hanger (and therefore the weight as well) must rotate along with the tonearm in the lateral plane so that it ignores the lateral component of the tonearm's movements. With the directly-hung counterweight described above, motions of the tonearm in both planes affect the motion of the counterweight. The counterweight 'sees' all the vectors and reacts accordingly. But with an intermediate hanger to run the string over, like is used for anti-skate, motions of the tonearm in both planes have only their vertical component transmitted to the counterweight. The counterweight 'sees' only vertical inputs, and accordingly moves strictly up and down, rather than like a pendulum. But the counterweight might still move in response to spurious inputs. So, give it a streamlined shape and immerse it a dampening fluid bath. The trough, like the hanger and the weight, will have to ride on the horizontal bearing housing. But this might not be a bad thing, since we removed the mass of the tonearm's rear extension and attached counterweight, and we might want to bump up the tonearm's lateral mass in isolation, like you do with the HiFi mod. Anyway, if decoupling the counterweight is what we want, then I can't think of many ways to decouple it further than this. I'm just not sure it would accomplish anything... |
Alex, that sounds like a workable idea. Maybe you should try a mock-up of it and see how it sounds. That's all I did. I had an idea, and tried it out to see if it worked to produce better sound for me. I'm sure that there are plenty of other improvements to be discovered, that none of us has thought of yet. The stuff that I made is just another "stepping-stone" towards improved sound and improved design ideas in tonearms. There will be others who are spurred on to make further improvements on top of what I have done, or entirely different directions. I'm just glad to have been able to contribute something back to the hobby. Regarding your particular design idea above, I think it is interesting to use a counterweight "lift" in front of the bearing, instead of a "see-saw" behind the bearing. This may have some interesting resonance effects, and possibly with careful implementation, could result in some resonance-reducing effects in the armtube. This would require experimentation. I think it would be worthy of trying out to see just what you can get out of it. After all, tonearms aren't the most complex items in the world, and most of us could actually build a whole tonearm that sounds quite good, if we set our minds to it. I enjoy seeing some other insights into the tonearm design issue, and love to see the seeds of innovations being brought to life. Go for it. |
Umm...mebbe, but I dunno. I think this one resides in the thought experiment file (along with most of my others :-) For one thing, it violates the KISS principle. For another, a string attached to the tonearm and pulled taut will have a very defined resonance, like a guitar string. But mostly, I just can't fathom why doing this would be beneficial. As opposed to your HiFi concept, which stemmed from an actual theory of its positive effect. I'd just be mucking around in the dark with no clear idea of why. This only occurred to me in response to your post about hanging counterweights, but taken to the max. If I have an opinion on this at all, it's that a conventional counterweight would probably be just as good or better in the real world. But if someone can explain to me why 'decoupling' the counterweight is ever attempted in the first place, maybe I'll change my mind and decide I could be on to something... |
It would have to do with resonance modes and reflections in the tonearm system, regarding the interconnected masses, and their positions, and the method of their contact with each other. I didn't do any measurements with my hanging counterweight. I just "theorized" that it might be good to get all the mass down at the level of the record(and remove the mass from being bolted to the armtube), and tried it. It was a little better than the Heavyweight. Sometimes you just have to go with your "gut feeling" and try things. |
Hi all, following Jeff Spall masterwork at www.william-reed.net/rega, I'm trying to apply some ideas to my RB 250 arm, and just wanted to share with your experience/thoughts: I already equipped my Rega 250 with an Expressimo endstub and counterweight and experienced a totally different sound from it. A good idea seems to have cw weight at a level which is as near as possibile at platter level. Now, while rewiring the arm with a cheap ultrathin wire I got (BTW it seems quite difficult to remove the enamel out of it), I thought of taking some more mass off the arm. The principle behind this would be to concentrate mass arm near the pivot, so reducing vertical inertia of the arm. So, last weekend, I cut out the lifter (most uncomfortable, but I decided to accept the drawback). Now, while Jeff pattern is spiral, Michell Technoarm has an array of 2 x 11 holes, all located in the inferior arm hemi-part. Thinking of mass distribuction, where the reduction of mass would give more benefits??? Thanks for sharing, Ciao, Stefano P.S.: Would be sensible taking the paint off with a sanding approach (a la Dremel) be a way to achieve a sort of hardening of Alu (similar to bead blasting)? |
Just be aware that when you are removing mass from the tonearm, you are affecting more than just vertical mass. There can be many consequences from doing this, that may or may not be what you want, unless you know what you are doing. Experimenting is fun, but can be expensive if you make mistakes. Regarding your question about sanding "hardening" the tonearm like bead blasting, the answer is no. Sanding does not work-harden the aluminum like bead blasting. |
Thank you Tom, I think (at least hope ;-) ) I'm aware of it. The overall resonance frequency of my actual setup would benefit from such a reduction. Should I need more mass, e.g. by changing cartridge, I thought I could add it nearer the pivot (or, e.g. by adding a damping foam inside the arm). Any recipe for DIY bead-blasting? |
Finally it plays! My TT, born as a string driven unit, build on a rectangular shaped plywood with cadberg and scheu pieces, now is a nice drop-shaped, multi sandwich, lead filled unit. It's suspended on air (inner tube). The motor unit drives the platter "crossing" a flywheel. The arm, now rewired, sounds much more precise and free of resonances. All in all, I'm very satisfied. LP sound quite good. I've only a residual hum (apparently not related to arm grounding, but I still have to investigate). Another 250 is sitting, waiting for a hanging cw test... Ciao, Stefano |
Stephano directed me to this thread. I'm glad he did :) I have a DL103D on a modified RB300 arm (expressimo back end, no VTF spring, Cardas wire, no plug in arm pillar base, VPI VTA adjuster, planed underside of headshell and end of arm tube). For years, my general approach to upgrading and tweaking has been to identify each individual weakness and fix it. As a result, my tonearm has been setup to reduce the presence region resonance/shrillness in this arm/cart combination. I've applied several suggestions from Thorsten (decoupling cart from headshell, lead tape around armtube at 1/3 length) and set VTF and VTA to reduce the shrillness. After reading a bit of this entire thread, I got a 3/4 ounce "lead substitute" weight, cut it in half, drilled the ends, loaded them with modeling clay (temporary glue) and stuck 'em on the axle nuts. There was an astonishing change as all previous customers have reported. - large increase in bass resolution and extension - soundstage is more solid, bigger, paradoxically with less well defined instruments - shrillness mostly gone (yea!) Then I noticed that the top octave or two were gone. So I decided to set up the parameters that are tuned by ear -- VTA, VTF, and anti-skating -- again. Azimuth, overhang and offset are set correctly. Instead of setting these by ear to reduce the shrillness while maintaining a decent tonal balance, I followed a method that's new to me. Basically, you set VTA to get best focus on a mono vocal record, then set VTF to get best dynamics and realistic tone, then set anti-skating to get equal dynamics in both channels. See this post by Bernhard Kistner at http://www.audioasylum.com/audio/vinyl/messages/45126.html. First, I got some 1 oz. lead weights and redid the outriggers. Then set the arm up twice. After the first go round, there was an upper bass/lower midrange boost. This was due to the lead band around the arm. So I removed it and started over. As things have turned out, there is now almost no distortion and the tonal balance is pretty much as it should be with only minor HF rolloff. Many many records that were really "zippy" and sibilant are very clean and natural now. Most bass is much tighter. Unfortunately, some old bass-shy Mercs are even more so, though the definition is stupendous. I'd like to throw my hat into the amateur physicist ring and open up an issue. Several people have noticed the change in soundstage similar to what I described. I believe that non-identical moments in the lateral and vertical planes are the culprit, causing crosstalk between the channels that has an unknown phase relationship to the signal in the originating channel. If the cartridge body was perfectly stationary, azimuth perfectly set, and the groove was carrying a signal in once channel only, then the stylus would be moving in a plane at 45 degrees to the record, perfectly aligned with the generator for that channel. Now, if the cartridge is allowed to move in the vertical plane, then the stylus motion, relative to the cart, would be in a plane that is no longer aligned to the generator. This motion, as a vector, has a small error component in the plane of the other channel's generator. Depending on the actual motion of the cartridge in the vertical plane, this error component may be in phase with the dominant signal, out of phase, partly delayed, and this relationship may vary with frequency, arm resonant behavior, the behavior of the as an oscillating system over time, etc. Fixing the arm in the lateral plane by raising the lateral moment, while the vertical moment stays relatively low to allow the arm to track warps, is equivalent to the situation I just described. Thank you TWL for the mod. - Eric, three years too late to this party |
just put this on the lenco thread. Thankyou Twl. simply astonishing... : Ok guys, here's the result on the RB300. IT WORKED! FIRST TIME! Ye gads. Dodgy phonos and no earth from the tonearm, and it does quite nicely. Now, with Michell Arm weight mod and my faithful Denon dl103r going through cardas cartridge pins into 4 feet of cardas tonearm wire, straight into the stepup, without the wire having run in for more than 1 hr it sounded ok, not brilliant, but ok. Bare in mind i'd just removed an OL Silver with all its superior price etc, that I'd been playing nonstop for a year plus. What i could now hear were vibrations (sibilence I think is the word) in the arm. Bass notes were muddied , imaging was lost, sparkle and prat werent there - Basically an inferior vibrating arm. Oh well, I need the money. Then lightening struck! I know, thinks I - I've got some of those fishing weights and bluetack that TWL was going on about, namely his hi fi mod!. Why not wack em on and see what happens. 2, yes 2 minutes later i had pressed the weights on with a liberal splodge of the blue tack, wacked a record on, and.... Bloody hell, i've got my OL SIlver back!!! This is not insignificant. This is not minor, this is £400 better and some. You know I think it might even be better than the OL Silver! What a laugh. All you RB300/RB250 people out there, hear me well. This is F.....g A! TWL should be knighted, rolled in clover, miss USofA'd to his heart's content and some. I'm in the next room typing this and it sounds better! Clearer, more focussed, more in the room.. just gone in for another listen, and wow it s cookin'. Lenco slam in spades. I'm a happy bunny. I've got a feeling we're heading towards OL Encounter land, as TWL himself said. Good thing I didnt try this on the OLSilver, I'd be weeping right now. Is anyone hearing what i'm saying... And the cardas cable still has to burn in. Hee Hee. |
Have not read through every thread here...but... I used to own a unipivot Lurne arm from France that had this arrangement built into a hollow tube that was fitted perpindicular to the arm tube toward the rear. The tube contained two weights that you would push through and position to stabilize the arm just like a tight rope walker...worked great. |
Hi Twl, and thanks for your reply. I'm still frankly astonished. Thankyou again. I posted a new thread of suitible superlatives in your name because i think you deserve it for this, but the moderators seem to have disallowed it. hence the new post on this thread. Congratulations again for your "mod" which i actually think is more a wonderful inovation in the field of tonearm design, even if others have tried to impliment such ideas independantly at other times. I am amazed when something like this isnt taken up by huge numbers of audiogonners, magazines and manufacturers. It is no joke to say that it has raised my Rb300 to my OLSIlver level, and even surpassed it slightly, probably helped by the 4 feet cardas rewire that obviated any joins to other wire before the phono stage. I shall rave on for a while about this one! |
Hi Twl, Gilbodavid pointed me to this thread after reading my post on the "lenco thread". I'm glad he did, because I was unaware of it and I'm very much interested, but, reading through it, I realised that, maybe, it's not suitable in my case as I have an ortofon 530 MM cartridge which has a compliance of 25(?), and as you point, it probably isn't enough to move the arm. What do you think? It would look cool, though... |
since this issues has popped up again i will take the opportunity of saying "thanks" for coming up with this tweak. I used the bullets on the side of my rb250[eom1] arm and all the usual descriptors in realtion to this tweak applies. better dynamics, and more definition overall. Pictures are posted here: 1. http://gallery.AudioAsylum.com/cgi/gi.mpl?u=33809&f=twl2.jpg 2. http://gallery.AudioAsylum.com/cgi/gi.mpl?u=33809&f=twl3.jpg |
Well, I bought a modified RB250 from a member who asked if I tried the TWL hifi mod. I said no but read the whole 23 pages printed out on this thread... I went & got some Blu tack (its called Fun Tack in Canada & sold by Lepage). But I could not find the bullet weights. Today, looking at some tiny metal cones I bought many years ago, I simply got out the tack and stuck a metal cone (about 1/2 onz weight) on each side.They are actually about 1/2 in dameter and again 1/2 high before developping a cone at the end. The difference is night and day! So much more information, so much more dynamics, detail and soundstage. But the sound!! Before I tought the sound was a bit flat and confined to the speakers. After this modification the instruments came really alive and I can hear so much more detail. Even my son comming down the stairs noted that the music really sounded wonderfull. All this comming off a Grado cart with a signature 10 needle. Would you beleive I get this from a Technics SL 1210 turntable with an acrylic platter and Maplewood brass heavy feet! I suggets you run , not walk to the store & get the $5 stuff - you will never take it off! Never mind reasoning it out or fear the bearing cant take the 1/2 onz load. I suggets you just try it.... Many years ago, people questionned big speaker wires; they reasoned this and that with very scientific measurements. They also questionned pointed feet for audio and speaker; they reasoned that one also... Just try it - you will never reason this mod again... |
Twl, I would be interested in knowing your thoughts on the groove tracer type design counterweight which appears to be a more mechanical amplification of the tecnoweight. Is it more beneficial for a low compliance suspension? Is it logical that the farther back from the bearing axis the side dampening effect is multiplied? Mmm....... Where might farther semi ridgid outboard weighting have diminishing returns.....is there a sweet spot or compliance ratio perhaps related to balanced off axis weighting related to dialing in suspension tuning? .... also any other currently avalible rega style counter weights that might be worth considering. Thanks in advance Jon |
Hi Twl and all other major contributers in this thread. I'm about to buy a OL Silver MKII, and during my research I stumpled across this thread. It seems like you have a brilliant mod on your hands Twl. I was wandering if you guys have experimented with different material for the weights? I googled "bullet weights" and noticed that you can get them in many different materials such as led, brass, steel, tungsten etc. Initially I though that tungsten would be preferreble, as you don't have to handle the not so health frinedly led, but the tungsten weights are about half the size of the led weights because of the increased density. Now I'm thinking that this might affect the mod, as the weights would be shorter and not stick out as far. Any comments on this would be greatly appreciated. I recommend you try and search for "bullet weights" and "worm weights" on the Bass Pro website (http://www.basspro.com), that will give you a lot of options. You can even get some in funky red colors :) Thank you in advance. Anders |