"Steep Tonearm?" Here's Why

An analogplanet reader asked about his "steep tonearm" after trying unsuccessfully trying to set the SRA to 92 degrees on his Soundsmith Boheme cartridge.

Wally Malewicz got ahold of a Boheme and measured it using his optical microscopy system and the above picture shows what he found: with the tonearm parallel to the record surface SRA was 96 degrees!

That means on a typical 9" tonearm one would have to lower the back of the arm approximately 16mm to achieve 92 degree SRA. That would result in one "steep" tonearm. It's probably beyond the range of most tonearms.

It's quite possible that all of these ruby cantilever/line contact styli are manufactured this way. That is unfortunate to say the least.

AndyPrice44's picture

That looks identical to the picture I wanted to post of my boheme cart. I would venture to say that it was designed to be this way. Why would soundsmith set the stylus in this manner? No matter what I do my tonearm doesn't have enough adjustment to get to 92 degrees. Since it seems like I am not going to be able to get a 92 degree SRA, How bad do you think this degrades the music? It sounds pretty good to my ear but, now that I know this, I will always wonder what if. This is going to bug the **** out of me. I can't afford a new cart right now. What would you guys do?

Thank you Mikey and Wally for taking the time to  address this with such detail.

Have a good one


Michael Fremer's picture

Andy, Soundsmith doesn't 'set the stylus'. These stylus/cantilever assemblies are purchased already 'set' that way. Since it seems that there's a uniformity to the setting, it seems possible that the angle is as intended by the company but that doesn't mean they are correct in so manufacturing them!<p>

The other possibility is that both Wally and I are misinterpreting the location of the contact area but I don't think so! In any case, I have emailed Soundsmith's Peter Ledermann to get his answer.

lovemesomevinyl's picture

I'm noticing the exact same thing on my Denon 103R recently "rebuilt" Soundsmith with thier ruby cantilever and nude contact line diamond stylus.   I'm wondering if increasing the tracking force might help acheive the correct SRA, or is this a no-no.  I'm already a little lost on what tracking force to use with my rebuilt 103R and the apparent SRA angle issue is worrying me more.  As it stands the sound on my VPI Classic after around 50 hours of use on the rebuilt cartridge is best described as bright.  Any suggestions or comments on increasing tracking force?

Michael Fremer's picture

Wow. Another cartridge using that ruby cantilever and nude contact line stylus and another one with high SRA!<p>

And it sounds bright, which is what one expects from high SRA. Increasing tracking force will lower the SRA and as long as you stay within the recommended range advised by Denon and/or Soundsmith, you should hear some improvement and I wouldn't worry about record wear.

AndyPrice44's picture

Would it be worthwile to lower the tonearm base and try to get it as close to 92 degrees as possible? As I stated before, This causes the tonearm to be pretty steep. The head of the tonearm where the cartridge is attached is half an inch higher than the rear. I guess my question is, should I leave the tonearm parallel to the record surface and live with the 96 degree SRA or should I have my tonearm at a steep angle trying to achieve a 92 degree that I will never get? The best it looks like I will be able to get is about 95 or maybe 94 degrees. Either way will be a compromise. Now I need to figure out which way to go.

Or....... I will have to save pennies for a new cartridge frown


AndyPrice44's picture

For the boheme cartridge, soundsmith recommends 1.3g VTF. I did try mine up to 1.4g for a very brief period. It didn't appear to have much change on the VTA. It didn't sound as good at this weight either. I didn't want to go higher in weight than this in fear of damaging the cart.

Michael Fremer's picture

Most cartridges have an acceptable range so even though Soundsmith specifies 1.3, chances are you can go up a bit and not have to worry about damaging anything. If it sounds worse, then of course stay at the recommended 1.3...but that assumes your gauge is 100% accurate!

deckeda's picture

And if you could manage to find or make something that only lowered the cartridge rear reletive to the head shell you wouldn't have to lower the tonearm as much. But if that would make the cartridge body touch the record, you're stuck.

Trivia: Dual used to include in their changers' head shell, a user-adjustbale cam that leveled/lowered the rear of the cartridge reletive to the head shell. The cartridge attached to a plate in the head shell that pivoted. The settings were "M" for multiple play (the default, since you'd bought a changer ...) and "S" for single play for the record-stacking averse. Those tonearms were high in the back to accommodate a stack of records and so the arm, head shell and cartridge were basically parallel when a few records were stacked. When playing just one record the S setting lowered the back of the cartridge to offset the angle of the tonearm.

AndyPrice44's picture

Thanks for reminding me of that. I must have overlooked it. I know a guy that runs a machine shop. I will get an exact measurement of what it needs to be to make my tonearm level with 180 gram records. It will also have a slight taper at the back end to help me get the 92 degree SRA. This seems like it would work but, with adding the extra weight, how is this going to effect resonant frequency. I might get it made out of some type of delrin or hard plastic to save weight. Still a compomise I shouldn't have to make.


My head hurts thinking of what to do..........

Michael Fremer's picture

The only way to know what the resonant frequency change might be would be to know the arm+cartridge's effective mass and the cartridge's compliance. From there it would be an easy calculation, though it's best to double check with a good test record the measures V and H resonant frequency.<p>

Delrin strikes me as a good choice. Let us know how it works out!

todd95008's picture

Just a thought here guys. that stylus looked a bit like a line contact to me (I have a AT-OC9ML/II line contact stylus). So I looked up Soundsmith and this Boheme cartridge also has a line contact stylus. From the picture it looks like the line contact (edge of the line contact) is actually less than 90 degrees  (backward a bit and not forward as the calculation shows) ??

I think Wally made an error with this since the angle of the line contact does not have to bisect the two angles depending on how the line contact is ground.

Take a close look at the photos and look for the line going backwards until it hits the intersection of the two upper facets ??

I'm guesing that if the tonearm was level this would now be close to 91 deg ? Hope this helps....

Now all I need to do is get the equipment to do this myself...



Michael Fremer's picture

No doubt by now it's obvious that these ruby cantilever/line contact assemblies appear to be uniformly manufactured but both Wally and I are pretty sure he's correctly identified the contact area and that his calculations are correct.<p>

However, I have an email in to Soundsmith's Peter Ledermann, so I'll get this resolved ASAP.<p>

Wally has taken another picture of the stylus that I believe clearly identified the contact area. I'll post it shortly.

Stephen Scharf's picture

You guys are assuming that the angle of rear edge of the sytus is at the same angle relative to the centerline of the stylus tip to shank as the front edge, and they aren't; they're assymetrical. So, in effect, Wally is mis-measuring the geometry. This is what is causing the over-estimation of SRA to be 96 degrees. 

bhutton13's picture

  Been following these SRA threads,my Soundsmith VPI Zephyr also looks to be at 95-96 degrees with the arm parallel. The cartridge sounds fantastic compared to the 10X5 it replaced, lows are more extensive and tight,but as already stated now that I know this,it is causing me to wonder what would be different at 92 degrees and what would be the best method to achieve it with a JMW9 memorial tonearm. Thanks in advance for any suggestions.


Michael Fremer's picture

The only solution is to get a spacer made that would, in effect, lower the back of the arm by raising the front. You could also get a thick mat, but I think the spacer makes more sense.<p>

It should be machined from a material like Delrin so you don't add too much mass at the headshell.

AndyPrice44's picture

I dont believe you can get to 92 degrees with the JMW9. I bottomed out my VTA adjustment on my JMW 10.5 trying to get there. It just cant be done without adding a spacer of some type. I know that the cartridge body on the zephyr is different from the boheme. Your cart body may be taller. As stated above, it will take 16mm of adjustment to get to 92 degrees. That is almost 3/4 inch. My JMW 10.5 doesn't have that much adjustment untill it bottoms out. Why would soundsmith make all their stylus set at 96 degrees? I cant figure that out. I cant say my cart sounds bad either. I think it sounds good. This whole issue just leaves me wondering if it would sound better if I could possibly get a 92 degree SRA. I may send peter lederman an e-mail about this to see what the reason is for the 96 degree angle.


Michael Fremer's picture

I've emailed him and will call if I don't hear back soon. The last thing I or Wally want to do is spread misinformation! But for now I don't think we are...

Fsonicsmith's picture

Something is not stacking up here. As most of us know, Peter L. charges more to retip the original cantilever with just a new stylus than to retip a cartridge with a new cantilever and stylus combination and he cautions on his website that retipping the existing cantilever may be not just more expensive but a LOT more expensive, if possible at all. Common sense tells us that is because it is less labor intensive to buy pre-assembled cantilever-stylus assemblies and install them. One can only imagine how taxing it would be to account for SRA when mounting a new stylus on an existing cantilever!

So all that said, if the cantilever/stylus assemblies Peter sources have 96 degree SRAs, how is it that Peter has so many grateful and loyal customers? Are we all deaf to the bright treble of 96 degree SRA? As it so happens, I have a Benz Glider SLO in it's stock configuration with very low hours on it mounted in a JMW 10.5 arm and a Benz Glider I purchased  new but had re-tipped by Peter with the mid-grade $250 nude contact line stylus mounted it in a VPI 9T. The re-tipped Benz does not sound bright to my ears, no brighter than the stock cartridge. It sounds beautiful. At the risk of turning this into some emotional outcry, which is hardly my intent,  I thank Peter for all he does-he is truly a "National Treasure" for us vinyl junkies-where will we be turning to when he hangs it up?  I don't mind the inquiry, but concluding that the the pre-manufactured assemblies are faulty or even highly problematic and challenging Peter to clarify how Wally's measurements are incorrect seems highly problematic to me.

AndyPrice44's picture

I hope I didn't come across as a product basher. Peter has always been helpful and easy to talk to. I think my boheme cartridge sounds good and have been happy with it. I am the type of person who is always trying to improve my setup. It does sound good but, could it sound even better? These SRA discussions just make me ask questions about my setup. I'm just trying to get the most from my rig, as most of us are. I wasn't trying to bash soundsmith or peter at all.


lovemesomevinyl's picture

I need to quit damaging and breaking all of the stock cantilevers on the cartridges I spent damn good money on in the first place. This is the true solution to my SRA, VTA, VTF and other turntable problems!!  

 I sincerely appreciate there are folks out there like Mr. Ledermann and Soundsmith who offer this extremely valuable service to people like me who for no good reason seem to like to break things.  I'm extremely impressed with his/Soundsmith's work.  Impressed enought that I just sent another cartridge I managed to karate-chop to cantilever off.  

As info, I did indeed increase the tracking force to something closer to what was originally suggested by Denon and the brightness I mentioned seems to have subsided. No doubt futher use and break-in will also help.  My problem is I can't help but always wonder to myself, do I have this thing set up correctly...it sounds good, but SHOULD it sound better, COULD it sound better.  

I appreciate Mr. Fremer and Mr. Ledermann's attention to these types of concerns. Tell me another hobby where you get this kind of attention and this kind of customer service. Many thanks to both of you. 

ianm0's picture

Edit: statement withdrawn due to possible observational difficulty which may lead to the dubious conclusion about inconsistency.

deckeda's picture

After you're logged into the site you see these on the right-hand side, where the login fields were:

  • Messages
  • My Gallery
  • My account
  • Create content
  • Log out

"My Gallery" is where you'll find images you've uploaded. Coincidentally it's also where you go to upload them.

Or you could use any of the zillions of file hosting sites out there such as Dropbox, Picasa and so on and then just link back to here, which is probably what you'd have to do even if the images were stored (i.e. hosted) here.

The link back to here could be a URL that takes us away from the site, or embedded so that it displays inline with your text. The first button on the second row of the editor says "Image" when you hover your mouse over it.

Good luck.

ianm0's picture

Edit: statement withdrawn due to possible observational difficulty which may lead to the dubious conclusion about inconsistency.

AndyPrice44's picture

I just wanted to add to this discussion for anyone else who may read this down the road. I have talked to Peter Lederman at soundsmith. He told me to ship my cartridge back to him. Soundsmith did adjust my SRA to 92 degrees and set the cartridge body in a new style housing. I am very pleased with the work they did and Peter was very easy to work with. All this was done at no charge to me. If you are having an issue with a soundsmith cartridge, I suggest contacting Peter, He is a good guy to deal with.


MichaelTrei's picture

I have often thought it would be cool if some accessory manufacturer made a kit with various wedges to fit between the cartridge and headshell to allow for this type of correction. They could be reversible allowing you to use each one to either increase or decrease the SRA depending on orientation, and you could have a set with half degree steps from 0.5 to 2.0 degrees. This would get you into a better adjustment range on some setups, or it can add some rudimentary SRA adjustment to Rega arms without resorting to those base shims.

I would suggest aluminum for better energy transfer to the headshell compared with something like Delrin. They can be thin enough so they won't add more than about one gram.

You could also have a version that slopes from side to side for azimuth adjustment on arms lacking that function.

john.tracy's picture

I purchased Peter's prototype Sussaro from Peter himself at 2012 RMAF. At that time Peter told me that the line contact of the stylus did not coincide with the centerline of the stylus and to not use the centerline for calculating SRA. The calculation above clearly is the centerline. In fact, the facet of the line contact is visible in the photo and it is not the centerline. I set my VTA by ear and the tonearm is not way to low are high.

Oystein's picture

Is there any service doing microscope + photo SRA test for a reasonable price? (Just the check, not repair). There seems to be a lot of homework + guesswork going on. I have a Lyra Atlas on a SME V arm, and *feel* that the arm should be even higher at the back, from what I hear (and what I can see using loupe glasses), but I don't really know, and the arm is now as high as it can go, so the next step would be a shim between the shell and the pickup. I am tired of the guesswork and would like a professional check. Advice?

AL447's picture

I've been using the USB microscope for SRA for about a year; several times per cartridge over that period, as the suspension settles. What I note from Wally M's photo at the top of the article is 3 faint intersecting lines: the top 2 form about a 60-degree included angle (vertex down), and the bottom line drops from their intersection, nearly perpendicular to the surface on which the stylus rests. That third line forms a roughly 35 degree angle to the front face of the stylus, and one of about 15 degrees to the back: If that line follows through to become the contact, then it is nowhere near the 96 degrees inferred from the calculation.

Since many of those posting here have VPI unipivot arms, why not dismount the arm wand, flip it on its back, and have a gander at the stylus from the groove's viewpoint?

jblackhall's picture

Just to clarify for future readers, the following post from 2010, now linked on the Soundsmith website, explains the visual error you're having with their OCL stylii.
I think you can actually see the line contact in the very nice close-up image you have posted above.

kevin.gray's picture

Good Post..

dordle12's picture

I read this post and, if possible, I'd want to give some fascinating topics or suggestions to you. Perhaps you could refer to this topic in your next article. I'd like to learn more about it! Thanks! fireboy and watergirl