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
Doug: Sorry to go off-topic for a sec, but I noticed at soundfountain.com Audio & Music Bulletin that you were using the RSR outer record ring. Did you make yours, or buy it complete? If it was the latter, what do you think of the pricing for the quality? From the text it seems implied that one could be fabricated for my SL-1200, though I don't know if it would fit in between the platter and my KAB damping trough...
Doug,

I know you posted about the ring, but damned if I could find it. I'd like to know what it cost too.

Joe
Over the last year as time/$ have permitted I worked on trying to get my system to sound like what I thought it should sound like. I played a horn growing up and used to go see the Minneapolis Symphony perform with my family along with many rock/jazz concerts. My goal was to try and duplicate what I felt an instrument sounded like when played. Sometimes because of the venue you had really good acoustics but even in a good hall there are better seats than others. I was trying to get a sound that I felt would be in the middle maybe 20 rows back. Depending on the venue and what type of music or concert it is, especially in my high school days at a rock concert in a hockey arena, then the ambiance and acoustics didn’t matter because you were so high.

Ahem, anyway, jazz, blue grass or acoustic concerts of late have been seen at The Egg in Albany, NY, which is an outstanding venue and has extremely good acoustics. After doing a lot of reading on acoustics and listening to my digital front end I decided I had to fix the room before it could ever be close to something I would enjoy. I thought about building different designs and could have since I’m fairly handy but in the end I bought manufactured bass traps called Realtraps. Spent $1300 and bought 6 bass traps and 2 high-frequency traps. The traps are sized 2’x4’ and 2” thick. I have the HF traps located approximately at the side mirror points. 4 bass traps up on the front wall and 2 bass traps on the rear wall. This made a major difference in sound quality, smoothing and dampening all frequencies without taking to much out of the room and over-dampening it. I could now turn up the gain on the pre-amp without over-whelming the room and rattling the windows and floor joists. I would like to measure the frequency response of the room but haven’t done that since I don’t have the tools yet. I’d bet there are still improvements to be had here.

I finally finished building and finishing the maple table to sit my VPI-TNT 3.5 turntable on. I anguished over where to put the table because I didn’t want to screw up the sound stage that the Gallo speakers portrayed on the front wall. In the end, I really didn’t have any good choices and with restrictions on phono cable leads to the pre-amp and room considerations I had to set the table up right in the middle of the front wall. So far, this seems to be ok and I haven’t noticed any detrimental sound stage effects.

Spent the last couple of weeks twiddling with the TNT and all the different adjustments you have to go thru to get it right. I had bought a Wally protractor to adjust the Benz Micro Lo.4 moving coil cartridge mounted to an Incognito rewired, VTA adjustable Rega RB300. I also installed the Expressimo heavy weight. I had done all of the adjustments and it sounded pretty good but the instruments semed “thin” or “light”. There was bass but not with authority. There were drums but no “snap” to them. So I bought some 10K pots and made up adjustable cartridge loading resistors and installed them in the CAT pre-amp. After experimenting with these for several days it seemed around 300 ohms gave good results so I made up fixed 324-ohm load plugs and installed them. This made a fairly large difference and things sounded much better but it still didn’t sound really great. Not bad, just not what I felt it should given the quality of components. Still sounded “thin” and “light” compared to what I felt was a more dynamic sounding CD player. This annoyed me big time! I had bought TWL’s Hi-Fi mod last fall but because my TNT was down while I built the maple table I had never installed them. I hand reamed the 12-gram lead bullets out to 21/64’s which made the side walls really thin but they now fit over the bearing cap nuts. Super glued them in place and let dry for a day. Went thru all adjustments again being particularly anal.

This next part is going to sound so much like “me too!” What can I say? Now, dynamics kick ass! Full, solid, correct sounding. Bass lines and drums sound just like you think they sounded when recorded. A full dynamic sound but not so much that you feel it’s wrong.

I’ll give a couple of examples. I have the Classic Records release, 200 gram, Cat Stevens, Tea for the Tillerman, side 1, Hard Headed Woman, huge difference in bass, acoustic guitar, voice. Very solid dynamic sound. The authority just sounds right. Even my tin-eared wife noticed it easily.

Next: Pink Floyd, Mobil Fidelity, DSOTM, side 1, Money, Us & Them - I wanted to break out my rolling papers on this change. Really fabulous!! Bass, guitar, voice, all so much more real and dynamic sounding.

Next: Steely Dan, MCA, Gaucho, side 1, Babylon Sisters, Hey Nineteen – This was fantastic! Drums sounded like they were in the room, voice, horns, guitar, just great.

Finally: The Dave Brubeck Quartet, Classic Records release, 200 gram, Time Out, side 1 – all of it. For my ears this is my test record. Fantastic sax, outstanding drum work and some fine bass lines. I actually feel Dave’s piano is the weak link on this record. Anyway, maybe 10x better. Not really sure how to quantify how much better but it goes from sounding pretty good prior to Hi-Fi mod to just plain F****** great!

Call it $1 buck for lead weight and $1 for super glue and I get this kind of improvement? I know the Incognito rewire and Expressimo heavy weight didn’t make this much difference and they cost several hundred. Yes, I think they made a difference but not to the degree these stupid lead weights made.

Maybe my best analogy would be when I installed a stage 3 hot chip in the computer of my turbo Audi S4. It went from sort of quick to bat out of hell get to know your local state trooper fast. It really made a quantum difference and that’s what these lead weights did. If Tom charged several hundred for it you would still after hearing the change think it was worth it. Thanks Tom! Now, where are those damn papers…

For pics of my system see:

http://forum.audiogon.com/cgi-bin/fr.pl?vevol&1054441548&read&3&4&
Hi guys, and sorry to Twl for the OT. I bought my RSR fully assembled from SoundFountain. I believe Rudolph's taking pre-orders for another batch.

My only niggle is that the edge was a bit rough. This doesn't affect functionality, it just doesn't look as pretty as it might. Rudolph has switched suppliers in an effort to improve this.

Joe,
My short user review is posted on the site linked by Zaikesman, scroll down to near the bottom. Short version: several worthwhile sonic positives, no sonic negatives.

I'll start a new thread (probably tomorrow) so as not to continue this hijack. I have information that will be of value to Zaikesman and perhaps of interest to others as well.
Mr. Slate, glad to have been of service to you.

Just a simple use of basic materials, properly applied.