Thread: Your own SRA pictures

Decided to play around with my crappy USB microscope today and check where my SRA for the Cadenza Bronze was set and I snagged a few pictures to share. I imported the .jpg images into AutoCAD to draw the lines and calculate the angles.

Turns out I am a bit tail down currently.

The most difficult thing I've found with using the USB microscope is to properly line it up perpendicular to the stylus itself when taking the pictures. If you're forward or backward of perpendicular it will skew your effort to draw lines and calculate the SRA properly.

The first picture shown here was one of the cooler looking ones I was able to capture of the Replicant Stylus facets but is not real usable since the camera was "around back" a bit too far (you can see the shadow of the rear facet).



Depending on where the lines were drawn and how the photos were taken (perpendicular wise to the cantilever/stylus) the other twenty-plus photos I captured all ranged from 91.3 to 91.7 degree SRA.




Tonight I adjusted the JMW 10.5 arm up some to what I think is closer to 92 degrees but will need to confirm the adjustment with more pictures tomorrow. So far, bumping the butt-end up a little has added a little more clarity and definition without loss of the bottom end at all.


Please share your pictures of SRA measurements if you have some.

Impressive work, Mike!

Ken

Now that's pretty cool.

Originally Posted by MikeCh

Decided to play around with my crappy USB microscope today and check where my SRA for the Cadenza Bronze was set and I snagged a few pictures to share. I imported the .jpg images into AutoCAD to draw the lines and calculate the angles.

Turns out I am a bit tail down currently.

The most difficult thing I've found with using the USB microscope is to properly line it up perpendicular to the stylus itself when taking the pictures. If you're forward or backward of perpendicular it will skew your effort to draw lines and calculate the SRA properly.

The first picture shown here was one of the cooler looking ones I was able to capture of the Replicant Stylus facets but is not real usable since the camera was "around back" a bit too far.



Depending on where the lines were drawn and how the photos were taken (perpendicular wise to the cantilever/stylus) the other twenty-plus photos I captured, all ranged from 91.3 to 91.7 degree SRA.




Tonight I adjusted the JMW 10.5 arm up some to what I think is closer to 92 degrees but will need to confirm the adjustment with more pictures tomorrow. So far, bumping the butt-end up a little has added a little more clarity and definition without loss of the bottom end at all.


Please share your pictures of SRA measurements if you have some.

To follow up on a point you made, even if setting SRA by ear (that eventually have to do anyway), don't be afraid to raise the arm. 92 degrees is a suggestion and many manufacturers suggest slightly less. I find that too often people have the arm too low in fear of too much upper octaves or to use a tone control to compensate for an issue elsewhere in the system. That's where the scope really helps! One will hear when the bass lightens and loses punch. In fact, it isn't bad to get to that place and then back off slightly.

Also remember that area that "magic" where everything comes into sharp focus happens within a very small area. So one can go up and down a lot and not hear a lot of change and then bang!

To my eye, those pics don't look right. It looks as though you have measured the trailing edge angle, not the stylus shank angle, and the tonearm seems way too high to me.

Fremer covers pretty well how to measure leading edge angle and trailing edge angle to get shank angle here: How to Use a USB Digital Microscope to set 92 Degree Stylus Rake Angle (SRA) | Analog Planet

These are measurements I took a while back with my 2M Black:

Thanks guys. It's pretty fun to see the stylus this close up.

Don, I agree it does look incorrect. However, the difference is in the stylus profile between the Ortofon Replicant and Shibata designs. With the Replicant, the lower most rear facet is where the measurement is taken from (as I understand it). With the Shibata and other "center contact patch" profiles (like my Dynavector 20X2H) the angle is determined like you have done, by splitting the shank down the middle to determine the correct SRA.

Originally Posted by MikeCh

Thanks guys. It's pretty fun to see the stylus this close up.

Don, I agree it does look incorrect. However, the difference is in the stylus profile between the Ortofon Replicant and Shibata designs. With the Replicant, the lower most rear facet is where the measurement is taken from (as I understand it). With the Shibata and other "center contact patch" profiles (like my Dynavector 20X2H) the angle is determined like you have done, by splitting the shank down the middle to determine the correct SRA.

Peter A. Started a thread on WBF and discussed setting up an Ortofon A90. Getting it right is harder with say the Ortofon than Lyra stylus.

Originally Posted by Myles B. Astor

One will hear when the bass lightens and loses punch. In fact, it isn't bad to get to that place and then back off slightly.

Also remember that area that "magic" where everything comes into sharp focus happens within a very small area. So one can go up and down a lot and not hear a lot of change and then bang!

Good point Myles. I will try this method after documenting where I'm at with the VPI VTA lift tower micrometer readings so I can easily get back to where I started if need be.

A question for my understanding. How close should the VTA be in relation to the STA , is there some magic number or should the stylus manufacturer dictate those requirements in their literature . And in reading, some talk about the Vertical Cutting Angle, how does one figure that out in relationship to the VTA and STA. Angleical Cutting Angle

Originally Posted by CPP

A question for my understanding. How close should the VTA be in relation to the STA , is there some magic number or should the stylus manufacturer dictate those requirements in their literature . And in reading, some talk about the Vertical Cutting Angle, how does one figure that out in relationship to the VTA and STA. Angleical Cutting Angle

What I've always started with for VTA is a level tonearm in relation to the platter as the starting point. I've found that in most cases, this will get you in the ball park for correct SRA. Using the USB microscope and software to draw/calculate the lines and angles will get you the next little bit closer. Then, as others have said, you need to season to taste from there with your own ears.

I have no clue regarding the Vertical Cutting Angle. That's a new one on me.

Originally Posted by MikeCh

Don, I agree it does look incorrect. However, the difference is in the stylus profile between the Ortofon Replicant and Shibata designs. With the Replicant, the lower most rear facet is where the measurement is taken from (as I understand it). With the Shibata and other "center contact patch" profiles (like my Dynavector 20X2H) the angle is determined like you have done, by splitting the shank down the middle to determine the correct SRA.

Huh, I had no idea. Well you learn something new every day!

Nobody else with SRA pictures to share?

If you don't use a USB microscope then how do you adjust your SRA accurately?

Mike, I get close by leveling the tonearm and using a magnifying glass to see where the stylus angle is approximately. I then do a rough VTA sweep with my tonearm's VTA adjuster while listening. I can get pretty close with this adjuster by sweeping up and down over a half inch or so. Then, when It sounds pretty good I leave the macro VTA alone and move to the micro VTA adjustment knob on the tower that my tonearm resides in. This adjusts in much finer gradations over a smaller distance. I listen carefully and select the final positioning with that knob. Both the macro and the micro VTA adjustments are done while the record is playing. It is actually rather fun and enlightening to hear the differences the different VTA positions sound. I also have the capability to mark the macro VTA positions for up to three different record thicknesses by using a scale that measures minute distances, if I so choose. It is then a simple matter to adjust the arm's macro VTA until the meter points to the saved mark. I would then fine tune by using the micro VTA adjuster. 91, 92 degrees, whatever the stylus angle turns out to be is unimportant to me, as there is enough variance in the way records are cut as to make one specific angle measurement right for some records, but wrong for others. If it sounds right, it is right.

Originally Posted by MikeCh

Nobody else with SRA pictures to share?

If you don't use a USB microscope then how do you adjust your SRA accurately?

I make use of the VTA bubble level of my Graham tonearm. Once it's leveled properly, I just make very minor adjustments on the fly if necessary.

Thanks Steve and Carlo, there's a lot to be said for listening for changes as SRA increases or decreases. This is something I've not radically tried myself. I'd love to have an integrated bubble level in my arm or even headshell to create the starting point.

I too set the arm level as a first step but generally go right for the USB microscope to check. Since I have the VPI VTA tower that's adjustable on the fly I need to play with that adjustment (more radically) while the stylus is in the groove. Might just try that tonight to hear how much difference I can detect (using Myles' reference: "One will hear when the bass lightens and loses punch. In fact, it isn't bad to get to that place and then back off slightly.")

Originally Posted by slowgeezr

Mike, I get close by leveling the tonearm and using a magnifying glass to see where the stylus angle is approximately. I then do a rough VTA sweep with my tonearm's VTA adjuster while listening. I can get pretty close with this adjuster by sweeping up and down over a half inch or so. Then, when It sounds pretty good I leave the macro VTA alone and move to the micro VTA adjustment knob on the tower that my tonearm resides in. This adjusts in much finer gradations over a smaller distance. I listen carefully and select the final positioning with that knob. Both the macro and the micro VTA adjustments are done while the record is playing. It is actually rather fun and enlightening to hear the differences the different VTA positions sound. I also have the capability to mark the macro VTA positions for up to three different record thicknesses by using a scale that measures minute distances, if I so choose. It is then a simple matter to adjust the arm's macro VTA until the meter points to the saved mark. I would then fine tune by using the micro VTA adjuster. 91, 92 degrees, whatever the stylus angle turns out to be is unimportant to me, as there is enough variance in the way records are cut as to make one specific angle measurement right for some records, but wrong for others. If it sounds right, it is right.

I am curious as to what tonearm you are using?

About 91.5 degrees. I decided to leave well enough alone.

Originally Posted by Wntrmute2

About 91.5 degrees. I decided to leave well enough alone.

Nice. What cartridge is this?

Originally Posted by MikeCh

Nice. What cartridge is this?

What???? You audiowannabe! You can't identify the catridge fom the stylus? Qhat kind of rookie are you???

A Benz Glider S. It is a Gyger(sp) stylus
Just kidding I assume you know.

edit: nevermind

While I was messing around with my MiyaJima Zero cartridge's SRA, I decided to recheck my Cadenza Bronze. I had to adjust it butt end up a little, and now it's time to adjust by ear:

Hey Mike thanks for thread very interesting...

Hi Kevin, you're welcome....glad you've enjoyed it.

My old USB camera really needs to be replaced. It's a cheapie Chinese Dino-Lite knock off that only runs on Windows XP and has a crappy stand so it's a real pain to use. I'm looking at a more narrow, pen-type USB microscope with integrated stand that hopefully will allow me to get closer to the stylus (and under the tonearm finger lift that protrudes on the VPI arms) for future pictures.