My thoughts on cartridge/arm set up

[jeff1225]

Peter,
I think it's very interesting that you use the Mint protractor for your SME. I was specifically told by the owner of Mint that his protractor does not work for the sliding base arms such as SME, it only works with a fixed base tonearm. I loved the Mint for for my Ikeda arm, I was very disappointed that it wouldn't work for my SME 3012R.

 

[PeterA]

Peter,
I think it's very interesting that you use the Mint protractor for your SME. I was specifically told by the owner of Mint that his protractor does not work for the sliding base arms such as SME, it only works with a fixed base tonearm. I loved the Mint for for my Ikeda arm, I was very disappointed that it wouldn't work for my SME 3012R.

Jeffrey, I exchanged a few emails with Yip about this very issue. He told me the real issue is that the fixed headshell does not have slots for sliding the cartridge back and forth to adjust effective length, the distance from the pivot point to the stylus tip. So, each MINT protractor for an SME arm has to be designed for a specific cartridge. One measures precisely the distance in mm from the center of the cartridge mounting holes to the stylus tip. With this figure, around 9.5mm, he then calculates the effective length of the specific SME arm with that specific cartridge and then is able to draw the correct arc line on the protractor. SME supplies the two null point dimensions for each arm which Yip then puts on the arc for cantilever alignment. My MINT protractor is for my AirTight Supreme cartridge and the V-12 arm. My MSL cartridge happens to have the same stylus to mounting hole dimension, so I can use the same protractor for both cartridges, luckily.

It is not ideal because Yip is dependent on the customer measuring this distance precisely, but it can work and he does, or at least he used to, have instructions for ordering his protractor for SME arms on the website. Perhaps he has since changed his policy or he feels differently about the 3012R arm, I don't know. I have found that my MINT protractor gives me better results than the SME supplied heavy stock protractor that came with the arm. I have two MINT protractors, one for my current SME V-12 arm and Supreme cartridge and one for my former 9" V arm and AirTight PC-1 cartridge. I have somewhere a photograph of the two protractors showing the difference in overhang and curvature of the two arcs. The one for the 12" is considerably flatter than is the one for the 9" arm. I will try to find the photo and add it later to this post.

 

[ddk]

David, this does indeed seem to be the case. I spent some time today with the MINT Protractor investigating the effect on overhang resulting from small changes to arm height. I first measured the thickness of the glass MINT protractor. I then measured the thickness of the average LP in my collection. I compared these to my average arm height level per my measurement methods and set up the experiment.

MINT Protractor: 3.0mm
Ave. LP: 1.5mm
Ave. arm height: 17.25mm

I took the difference between the MINT and LP thickness of 1.5mm and added this to my arm height so that the surface of the MINT relative to the arm height (VTA and SRA) would mimic the condition when the stylus is on an average LP.

17.25mm + 1.5mm + 18.75mm.

I raised and set the arm height to this 18.75mm level. This is a true representation of the arm height when playing an average LP except that the stylus is now resting on the inscribed arc line on the MINT protractor rather than in the groove of the thinner LP. That arc line looks to be slightly wider than the 0.1mm thickness of a human hair.

I now adjusted the arm up and down by 1.5mm in each direction which is slightly more than I raise and lower the arm up or down when playing the various LPs of my collection. I wanted to see how these changes in arm height would affect the movement of the stylus tip relative to the inscribed arc line on the MINT protractor.

With the arm at 18.75mm, the stylus made contact with the center of the arc line throughout its entire length. This was not visible by my naked eye, so I used the 10X loupe supplied by MINT and a good lighting source to confirm.

I raised the arm by 1.5mm to 20.25mm and looked at the stylus through the loupe. It was extremely hard to see the exact amount of movement, but it looked like the stylus now rested on the inner edge of the arc line representing the outter most grooves of an LP. Toward the spindle, or inner groove of the LP, the stylus was on the line.

I then lowered the arm by 1.5mm to 17.25mm and again looked at the stylus through the loupe. Now it appeared to rest on the very outside edge of the arc line at the outer groove of the LP. Near the spindle, the stylus was again on the line.

So the only detectible movement in overhang was at the outer part of the arc and it was only visible through the 10X loupe and it only changed by roughly the thickness of the line or 0.1mm. I could not see any movement at the inner part of the arc.

So it seems as though David was correct all along. The change in overhang through an arm height adjustment of 3.0mm with a 12' tonearm is not detectible by eye and only barely visible through a 10X loupe magnification. As shown previously, the change in VTF is also extremely small and does not change if measured to 1/10th of a gram and it is only barely detectible if measured to 1/100th of a gram at the extremes of my 2.5mm changes in arm height.

Perhaps others can try to do these measurements and get different results, but based on my fairly careful attempts to understand what is going on at this extremely small scale using typical analog measurement devices for cartridge and arm set up, I can only conclude that the changes or effects that I hear in sonics when adjusting arm height are primarily the result of SRA changes of 1/10th of a degree for each 0.5mm change in arm height, and not the almost undetectable changes in the other parameters of VTF and overhang. This is as I suspected, but I wanted to see the actual data collected when trying to measure this stuff.

View attachment 40439

I’m trying to understand the advantage of using the Mint over a protractor after all using the same curve geometry the null points are the same, what am I missing?

david

 

[Mike Lavigne]

I’m trying to understand the advantage of using the Mint over a protractor after all using the same curve geometry the null points are the same, what am I missing?

david

it's really about a single use tool with zero ambiguity. can only work with one arm and one spindle to pivot distance and one exact spindle size. perfectly legible etched glass and easy parallelogram for cantilever alignment. the visuals of a stylus on the very prominent thin black line is easy for old guy eyes. you can be very precise as the line will easily reveal if you are even slightly forward or backward. you can be exact.

a Mint LP protractor can only do one thing, but does it perfectly and is a no brainer. slap it on, freeze the platter, and easy peasy.

and it's relatively cheap and reasonable to have the right one for a number of combo's.

 

[ddk]

it's really about a single use tool with zero ambiguity. can only work with one arm and one spindle to pivot distance and one exact spindle size. perfectly legible etched glass and easy parallelogram for cantilever alignment. the visuals of a stylus on the very prominent thin black line is easy for old guy eyes. you can be very precise as the line will easily reveal if you are even slightly forward or backward. you can be exact.

a Mint LP protractor can only do one thing, but does it perfectly and is a no brainer. slap it on, freeze the platter, and easy peasy.

and it's relatively cheap and reasonable to have the right one for a number of combo's.

So it comes down to old man eyes, that I get!

david

 

[PeterA]

I’m trying to understand the advantage of using the Mint over a protractor after all using the same curve geometry the null points are the same, what am I missing?

david

Hi David, I have little to no experience with other protractors, so I do not know its advantages over others, nor am I suggesting that it is better than what else is available. It simply happens to be the protractor with which I have become familiar. I have really only used SME tonearms on SME turntables, so my needs are very simple and specific.

I bought a MINT protractor after witnessing a demonstration of how to use it. I was particularly impressed with the alignment lines at the null points to adjust Zenith, or the rotation of the cartridge about the stylus in the head shell. SME arms do not have slots, but the mounting holes are slightly larger than the screws, so there is some room for adjustment. These lines at the null points make aligning the cantilever extremely easy and precise. I have seen other protractors and alignment jigs which have a bunch of parallel lines with which one is asked to line up the edges of a cartridge. This seems a bit more cumbersome. The MINT method seems to be much more straight forward and accurate.

Here are some photos which illustrate this. Notice the double lines to adjust for parallax effects. One other advantage is price. The Mint costs about $110 and includes the 10X loupe and a 3X lighted magnifying glass for those aging eyes.

 

[PeterA]

it's really about a single use tool with zero ambiguity. can only work with one arm and one spindle to pivot distance and one exact spindle size. perfectly legible etched glass and easy parallelogram for cantilever alignment. the visuals of a stylus on the very prominent thin black line is easy for old guy eyes. you can be very precise as the line will easily reveal if you are even slightly forward or backward. you can be exact.

a Mint LP protractor can only do one thing, but does it perfectly and is a no brainer. slap it on, freeze the platter, and easy peasy.

and it's relatively cheap and reasonable to have the right one for a number of combo's.

That is an excellent summary, Mike. The MINT is a single use tool with a high degree of precision. Here are two more photographs. The first one clearly shows the different radius arcs for my 9" and 12" arms.

View attachment 40452

View attachment 40453

 

[ddk]

Hi Peter,

Thanks for the picts, and that notch in your cartridge casings sure helps!

david

Hi David, I have little to no experience with other protractors, so I do not know its advantages over others, nor am I suggesting that it is better than what else is available. It simply happens to be the protractor with which I have become familiar. I have really only used SME tonearms on SME turntables, so my needs are very simple and specific.

I bought a MINT protractor after witnessing a demonstration of how to use it. I was particularly impressed with the alignment lines at the null points to adjust Zenith, or the rotation of the cartridge about the stylus in the head shell. SME arms do not have slots, but the mounting holes are slightly larger than the screws, so there is some room for adjustment. These lines at the null points make aligning the cantilever extremely easy and precise. I have seen other protractors and alignment jigs which have a bunch of parallel lines with which one is asked to line up the edges of a cartridge. This seems a bit more cumbersome. The MINT method seems to be much more straight forward and accurate.

Here are some photos which illustrate this. Notice the double lines to adjust for parallax effects. One other advantage is price. The Mint costs about $110 and includes the 10X loupe and a 3X lighted magnifying glass for those aging eyes.

View attachment 40450

View attachment 40451

 

[jeff1225]

Jeffrey, I exchanged a few emails with Yip about this very issue. He told me the real issue is that the fixed headshell does not have slots for sliding the cartridge back and forth to adjust effective length, the distance from the pivot point to the stylus tip. So, each MINT protractor for an SME arm has to be designed for a specific cartridge. One measures precisely the distance in mm from the center of the cartridge mounting holes to the stylus tip. With this figure, around 9.5mm, he then calculates the effective length of the specific SME arm with that specific cartridge and then is able to draw the correct arc line on the protractor. SME supplies the two null point dimensions for each arm which Yip then puts on the arc for cantilever alignment. My MINT protractor is for my AirTight Supreme cartridge and the V-12 arm. My MSL cartridge happens to have the same stylus to mounting hole dimension, so I can use the same protractor for both cartridges, luckily.

It is not ideal because Yip is dependent on the customer measuring this distance precisely, but it can work and he does, or at least he used to, have instructions for ordering his protractor for SME arms on the website. Perhaps he has since changed his policy or he feels differently about the 3012R arm, I don't know. I have found that my MINT protractor gives me better results than the SME supplied heavy stock protractor that came with the arm. I have two MINT protractors, one for my current SME V-12 arm and Supreme cartridge and one for my former 9" V arm and AirTight PC-1 cartridge. I have somewhere a photograph of the two protractors showing the difference in overhang and curvature of the two arcs. The one for the 12" is considerably flatter than is the one for the 9" arm. I will try to find the photo and add it later to this post.

This makes sense Peter. Yip asked me: "how many cartridges do you have?" When I told him over 30, he said the Mint wouldn't work for me. I didn't understand why he asked that question until your explination.

 

[PeterA]

This makes sense Peter. Yip asked me: "how many cartridges do you have?" When I told him over 30, he said the Mint wouldn't work for me. I didn't understand why he asked that question until your explination.

Wow, 30 cartridges. That is quite a collection. My understanding is that Yip only needs the mounting hole to stylus distance if the headshell has no slots. Otherwise, if one uses one arm that has a slotted headshell, then I would think he could use the MINT and just adjust for each cartridge in the headshell. With your 3012R and 30 cartridges, the MINT makes no sense. You would need 30 different samples.

My needs are so simple and specific, that the MINT has worked out well. I've also been interested in the Uni Pro from Germany. It is more universal, but is quite expensive.

 

[jeff1225]

Wow, 30 cartridges. That is quite a collection. My understanding is that Yip only needs the mounting hole to stylus distance if the headshell has no slots. Otherwise, if one uses one arm that has a slotted headshell, then I would think he could use the MINT and just adjust for each cartridge in the headshell. With your 3012R and 30 cartridges, the MINT makes no sense. You would need 30 different samples.

My needs are so simple and specific, that the MINT has worked out well. I've also been interested in the Uni Pro from Germany. It is more universal, but is quite expensive.

I use the paper template that came with the arm to align the cartridge and then use the DB Systems Protractor to dial it in to perfection. I switch carts every few weeks or so, one of the reasons I need an arm with a removable headshell.

 

[microstrip]

This makes sense Peter. Yip asked me: "how many cartridges do you have?" When I told him over 30, he said the Mint wouldn't work for me. I didn't understand why he asked that question until your explination.

Congratulations! Do you have an headshell for each of them?

 

[PeterA]

Yeah I never responded to your thread, because back then (or ever since) you had not answered my challenge: how small a change anywhere is acceptable to you. Herein, we are talking about minuscule angle changes and you seem to indicate they are important; back in the other thread, what are you willing to accept in terms of changes to other parameters? You don't have to answer this here. What if I were to point out that we'd probably all go crazy if our turntable speed was 0.1% or even 0.05% off, and can only render a 1kHz tone as 1001 or 1000.5 Hz. Just something to think about: what is really negligible in the LP analog world.

Thanks Ack. Here is your question again from my system thread, and I will here try to answer your question as best I can.

OVERHANG: I am willing to accept a change in the overhang parameter that is not visible to the naked eye in reference to my use of the MINT protractor. I have looked at the effect on overhang with the raising of my arm from the reference of 17.5mm up or down by 1.5mm. The change in overhang is not visible to my naked eye and only slightly visible through 10X magnification, so I am willing to accept that change in the overhang parameter.

VTF: I have measured the VTF changes that occur during the range of my arm height changes. I have taken that value of 0.049g and without changing any other parameter have tried to hear that difference in VTF. I can not hear it in my system, so I am willing to accept that degree of change in VTF.

Azimuth: Should not change with my arm height changes, but Azimuth is one parameter that is not adjustable with my SME arm.

Zenith: No noticeable change with arm height change according to confirmation with my MINT protractor null point lines.

SRA: 3/10ths of one degree. This is the parameter that changes the most and I think it is responsible for the majority of the change in should.

I have looked at these parameters and made measurable observations. They may be incorrect. If others see flaws in my calculations or observations and have different opinions about cause and effect, I welcome additional comments to further the discussion.

 

[ack]

So take your VTF measurements: your 0.049g margin off of 2g is roughly 2% - that's +-1%. You accept 2% VTF variation and apparently consider this negligible.

Next, take platter speed: would you accept a 2% variability, and consider it negligible as well? I don't. For a 1kHz test tone, it would mean my turntable would render it anywhere from 990Hz to 1010Hz. I go crazy when I am beyond 0.1% accuracy, never mind 2%.

My conclusion of what you consider negligible in this matter has always been that you are rather partial to what you want to prove to yourself: that SRA/VTA is the only thing that really matters.

 

[jeff1225]

Congratulations! Do you have an headshell for each of them?

Thank you. I do have a headshell for each of these cartridges. I have:

-SME S2
-Yamamoto Wood
-Yamamoto Carbon Fiber
-Yamamoto Titanium
-Audio-Technica AT-LH18 (awesome with the Denon 103R)

 

[PeterA]

So take your VTF measurements: your 0.049g margin off of 2g is roughly 2% - that's +-1%. You accept 2% VTF variation and apparently consider this negligible.

Next, take platter speed: would you accept a 2% variability, and consider it negligible as well? I don't. For a 1kHz test tone, it would mean my turntable would render it anywhere from 990Hz to 1010Hz. I go crazy when I am beyond 0.1% accuracy, never mind 2%.

My conclusion of what you consider negligible in this matter has always been that you are rather partial to what you want to prove to yourself: that SRA/VTA is the only thing that really matters.

Ack, I am not saying that SRA is the only thing that really matters. I acknowledge that other parameters change, I am just saying that I think that small changes in SRA matter more, or are more audible than small changes in overhange or VTF. Other parameters don't change with arm height, including platter speed. Platter speed has absolutely nothing to do with this discussion. The 0.049, lets just say 0.05, VTF is the whole range for my arm height adjustments. However, it is really only half of that variance from my base VTF of 2.0g. Look at the data in the OP. At my lowest arm setting the VTF is up by 0.019g. At the highest arm height, it is down by 0.03g. In other words, for my average records that have the reference arm height, the VTF is 20.g. The variance at the extremes is more like +-1/2%. I can not hear that change in VTF when I leave all other parameters unchanged. Can you hear the difference between 2.0g and 2.025g? Even if I could hear it, it would be much less important than a 1.5mm change in arm height. That is my point.

I have no idea why you want to introduce platter speed into a discussion about tonearm parameters. I know that my SME has a measured error of 0.003% or something when I measure it while playing music using the Sutherland TimeLine device. I do not think I would accept a 2% variance, but I have not listened to a speed error of that magnitude. Each of us is sensitive to different things. I do not follow your logic at all. That's fine if you think I am partial to what I want to prove to myself. You should do your own measurements and tell me what amount of error you accept. I answered your question, now answer mine and prove that changes in other tonearm parameters that result from adjusting arm height are more important than SRA. I'm curious to see your reasoning and your data to support your conclusion.

 

[Stacore]

Peter,
I think it's very interesting that you use the Mint protractor for your SME. I was specifically told by the owner of Mint that his protractor does not work for the sliding base arms such as SME, it only works with a fixed base tonearm. I loved the Mint for for my Ikeda arm, I was very disappointed that it wouldn't work for my SME 3012R.

That's very interesting as Yip made me a dedicated 3012R + EMT930 protractor in 2011, so did late Wally Malewicz (from whom IIRC the design originates) shortly before him passing away. I use the sliding base of the arm to make the tip of the diamond (fixed shell cart or not, it doesn't matter) to follow the correct P2S curve. It is what matters in the first run.

Cheers,

 

[microstrip]

That's very interesting as Yip made me a dedicated 3012R + EMT930 protractor in 2011, so did late Wally Malewicz (from whom IIRC the design originates) shortly before him passing away. I use the sliding base of the arm to make the tip of the diamond (fixed shell cart or not, it doesn't matter) to follow the correct P2S curve. It is what matters in the first run.

Cheers,

It is not possible to design an optimum protractor for a variable stylus to pivot and variable pivot to spindle distances, as it happens when we use a non-slotted original SME headshell. Probably they take a typical value for this purpose and it shows to be good enough.

IMHO the SME supplied protractor or equivalent is good enough for this purpose.

 

[PeterA]

It is not possible to design an optimum protractor for a variable stylus to pivot and variable pivot to spindle distances, as it happens when we use a non-slotted original SME headshell. Probably they take a typical value for this purpose and it shows to be good enough.

IMHO the SME supplied protractor or equivalent is good enough for this purpose.

Fransisco, Yip does not take a "typical value for this purpose". For SME arms with non slotted headshells, Yip requests that the user supply the cartridge mounting hole to stylus distance in mm. He adds this to the pivot to mounting hole distance of the arm, taking into account the offset angle of the headshell to calculate the actual effective length. This is then used to draw the arc on the protractor. That is why with SME arms, MINT protractors are specific to the arm and cartridge. I have ordered two MINT protractors for SME arms from Yip. They are incredibly accurate.

Good enough: it all depends on what you think is "good enough". I used the SME supplied protractor and it was fine. The challenge is standing over it precisely to align the arm with the outline. How does one know that his line of sight is square? It is an approximation at best, but it works just fine. Then I witnessed a friend use the MINT protractor. I ordered one for my SME V. The first thing I did was check to see how accurate my existing alignment was that was based on the SME protractor. Well, it was off by about 1mm at the outside of the MINT arc and 0.5mm at the inside. The sound was fine, but after I reset overhang with the MINT, it sounded slightly better. Yes "slightly better" is a subjective and relative term, but I preferred the sound with the more accurate protractor. The best thing about the MINT, which is completely absent from the SME, is zenith alignment at the null points. This is another parameter that matters with certain stylus shapes. Without being able to visually check how square the cantilever is at the null points, how does one know if zenith is correct? Of course it matters if the stylus is mounted squarely in the cantilever tip, but the SME protractor does not help here either. I am not aware of any protractor that can confirm with accuracy the mounting of the stylus. Simply aligning the edge of the headshell with the edge of the cartridge may be "good enough", but aligning the actual cantilever with tiny lines at the null points with a 10X loupe is more accurate.

None of this matters if the end user does not hear the difference or does not care about precision. Good enough is always good enough, until it is no longer.

 

[Stacore]

It is not possible to design an optimum protractor for a variable stylus to pivot and variable pivot to spindle distances, as it happens when we use a non-slotted original SME headshell. Probably they take a typical value for this purpose and it shows to be good enough.

IMHO the SME supplied protractor or equivalent is good enough for this purpose.

Yes Micro, me bad, you right of course. I've been using fixed shell carts (SPU and FR7f) so one parameter (stylus to pivot) is fixed and hence my too quick comment.

Cheers,