SRA Setting, Is it worth the bother

OK, I understand that part as well. the groove walls aren't at an incline induced from the rake angle of the cantilever holding the cutting blade. The cutting blade was still perpendicular to the plate. The increased rake angle of the cantilever allowed more down force to be applied to the cutting blade, without adding more down force to the cutting head. Or another way to look at it, they could reduce the downforce some of the cutting head while retaining the downforce of the blade.

The cutting heads changed their angle at which the grooves were cut, from 15 degrees to 20 degrees as a baseline. The record industry were trying to standardize the tracking angle, in the name of improving record playback.
 
The whole idea is to have the best sounding setup so VTA on the fly will get you to the same place if it is that noticeably better if SRA set correctly.

And if it sounds a bit better at a slightly different angle you'll get that too.

I'll stick with adjusting by ear. Seems straighter to the point and easier to do.
 
Reading all of this causes me some basic confusion, at least in terms of.....terms. Can someone please tell me why the term "VTA" is still being used? If what we are trying to determine is the angle at which the stylus meets the record groove, what is it about "SRA" that does not fully meet our needs? Can it not be said that VTA might be useful IF we were able to conclude that the manufacturer positioned the stylus at precisely 90deg. on the end of the cantilever? Most of what I've read says that is not the case, so again, is not the SRA what we are after? Should we all not just focus on finding a tool that tells us this angle? I've tried it with a USB microscope and a helpful program that provides measurements for angles and found it interesting if not even slightly informative, but man.....there is certainly a lot of room for error. Wish someone a lot smarter than me would come up with a tool that allowed this angle to be calibrated with a much lesser degree of fuss and frustration! In a pretty feeble attempt to measure the angle of my stylus (Sumiko Blackbird) this is what I have arrived at:

upload_2018-11-12_9-4-13.png

Clearly, there is much room for error and therefore improvement, but I get the sense that I'm "in the ballpark" at least (the reading, in case you can't see it, is 92.52deg.) and have then been able to adjust the SRA by ear.....welcome all comments.

PS - Click on the image to enlarge.....
 
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I recall Vertical Tracking Angle and Stylus Rake Angle define a difference with a distinction where one relates to duplicating the cutter stylus angle of motion, and the other the precise angle of the cutting edges. How well they coincide in one setting at playback for a deep and relative sharp contact patch ratio is directly related to how the cutter head and stylus related to the lacquer during the recording.
Chances of getting both right in one setting will depend on the example at hand.
 
Reading all of this causes me some basic confusion, at least in terms of.....terms. Can someone please tell me why the term "VTA" is still being used? If what we are trying to determine is the angle at which the stylus meets the record groove, what is it about "SRA" that does not fully meet our needs? Can it not be said that VTA might be useful IF we were able to conclude that the manufacturer positioned the stylus at precisely 90deg. on the end of the cantilever? Most of what I've read says that is not the case, so again, is not the SRA what we are after? Should we all not just focus on finding a tool that tells us this angle? I've tried it with a USB microscope and a helpful program that provides measurements for angles and found it interesting if not even slightly informative, but man.....there is certainly a lot of room for error. Wish someone a lot smarter than me would come up with a tool that allowed this angle to be calibrated with a much lesser degree of fuss and frustration! In a pretty feeble attempt to measure the angle of my stylus (Sumiko Blackbird) this is what I have arrived at:

View attachment 1328775

Clearly, there is much room for error and therefore improvement, but I get the sense that I'm "in the ballpark" at least (the reading, in case you can't see it, is 92.52deg.) and have then been able to adjust the SRA by ear.....welcome all comments.

PS - Click on the image to enlarge.....

I adjust the angle at which the stylus meets the record groove with one single knob, and they call it VTA on my TT. The term used doesn't bother me, whatever you would like to use is ok with me. The thought would be to obtain the best possible sound quality from the system by setting angle of the needle in relation to the vinyl medium.

Seems way easiest to eyeball it close then listen until you have it sounding it's very best.
 
Something like a Fozgometer for SRA.

Thank you dosmalo, and I indeed have tried using the Fozgometer with somewhat mixed results.....a friend who is more savvy than I has one and brought it over, set it up, and the readings were inconsistent. I had new batteries on hand as I had read that may affect the readings and even tested with my volt meter to make sure.....still, using the test record he also provided, inconsistent. However, I appreciate your thought and suspect that we may not have been using it correctly.

I adjust the angle at which the stylus meets the record groove

Yes, I am of the same opinion. That is why I am still wondering why they call it VTA as the setting on every turntable I've ever seen. Not that they don't exist, but I've not seen it called "SRA" on a turntable, and that is what I understand we are adjusting. I just wanted to get some clarity for my brain here, but after just listening for 2 hours, I'm pretty sure that whatever that angle is, I'm dang close because I really like what I just heard! You had to be there.....:thumbsup:

PS - Listen, often.....
 
Again, SRA relates to the facet angle, VTA relates to cutter motion angle, a distinction with a difference.
The first being off affects hf resolution, the second being off affects accurate dynamic response linearity.
A spherical tip is pretty much immune to SRA problems as a dull tracing tool, a Shibata or other long narrrow contact patch tip will be affected as a much finer resolution tracing tool. VTA affects stylus motion regardless, but more so with the finer tip profile at higher freqs.
 
IME a Fosgometer is for Azimuth only (left to right when viewed from the front) and even still can result in a poor alignment of the stylus in the groove if the internal components of the cartridge are not well oriented. The Fosgometer or a simple oscilloscope only lets you see the electrical alignment of the cartridge to the groove and not the physical alignment of the stylus in the groove. I own both and my preference is first looking at the stylus under a microscope to make sure it's aligned properly, ZYX Airy 3 Azimuth.JPG and not skewed, and then setting Azimuth with the stylus down on a front surface mirror.

WRT SRA it's theoretically 92 degrees using a USB microscope to look at the stylus at the edge of the record.
Koetsu Rosewood SRA.jpg
 
As mentioned SRA and VTA are two different things. VTA always applies while SRA is related to the stylus tip onlry and is important when you have line contact stylii. Both are interdependent though so you cannot change SRA without changing VTA.

That said, SRA is important for the stylus to fit the groove and affects friction and noise. A badly setup SRA will increase friction and noise. Most cartridges will however have a target set SRA already and those stylii that are off should be discarded IMO.
 
And as noted a cheap USB microsope is often sufficient to check SRA.

SRA%20OM40.001.jpeg
 
Thomas and antennaguru, it would appear we all are really close in terms of the angle we have set SRA to, but that's just judging from the pictures and admittedly, mine is not such a good one but I believe sufficient to see the angle. I used a free tool called MB-Ruler to measure the angle best I could.

Thomas, can you provide a link to the microscope you used? I borrowed one from a friend (same friend with the Fozgometer) but we both agreed that it is not really up to the task. Focus at such a near-field was impossible to attain. I really like how yours shows the stylus so clearly. Nice work!
 
IMO 92 isn't perfect for every cartridge but it makes a reasonable starting point and then you listen, and fine tune with tonearm height until the stereo image locks in. I don't own any Fritz Geiger styli so have no experience with those.

The other challenge is that we're not taking the effect of stylus drag into account, which will surely change the angle of the stylus. We use our USB microscope at the edge of the record with the platter stopped to get it to focus and get a picture that we can see reasonably clearly. Well, if the platter were moving the dynamic SRA would become a little more vertical that the static SRA that our pictures show.
 
Thomas and antennaguru, it would appear we all are really close in terms of the angle we have set SRA to, but that's just judging from the pictures and admittedly, mine is not such a good one but I believe sufficient to see the angle. I used a free tool called MB-Ruler to measure the angle best I could.

Thomas, can you provide a link to the microscope you used? I borrowed one from a friend (same friend with the Fozgometer) but we both agreed that it is not really up to the task. Focus at such a near-field was impossible to attain. I really like how yours shows the stylus so clearly. Nice work!

At the moment I am a bit busy with other things but I look it up during the weekend. But it is really nothing special about it.
 
Hi Guys Just to clarify my understanding of VTA & SRA
- VTA, vertical tracking angle is the angle the cantilever makes with the surface of the record.
- SRA, Stylus rack angle is the angle of the stylus as it plays an LP at the correct tracking weight. (We hope that the manufacturers set this correctly, but I have no confidence that they do)

People often incorrectly say "Adjusting VTA" when they mean "Adjust tonearm height". Adjusting tone arm height will affect both the VTA and SRA of the cartridge. But it is confusing to use this term. However to get the correct SRA, sometimes you need to literally shim the cartridge body, as I had to do with my set up. With the cart I am currently using I could not get the correct 92 deg setting with tone arm height adjustment alone.

Just found my 1st post 1968 LP that did not sound good at my current SRA setting, so I put a 2 x 2mm thick LP's under it & sound improved markedly. So the rule (92 deg's) does not apply to all post 1968 LP's and as people have advised must be effected by different cutting head angles from the various lathe manufactures.!! (so I now need a sticker system, 1 dot add LP, 2 dot add 2 LP!!) Oh the quest for perfect sound.

Cheers
 
Hi Guys, Well I think I have solved the problem of playing pre 1968 LP's with a dialed in SRA for post 68 LP's. (well for me anyway, I had to raise my arm up, considerably)
What I have come up with is just to a bubble wrap cut to the shape of the LP under the pre 68 LP. Just listening to Mercury Living Presence Sampler LP (cost new 98 cents!!) disc & really sounds stunning.

Happy Christmas everyone Derek
 
Hey Derek, and a happy one to you as well!

really sounds stunning

But.....UH-OH.....can you hear it??? Listen closely.....there are rumblings in the distance.....getting a little louder.....after all this time and effort, trying everything from deer hide to cork to space-age polymers in an attempt to find the perfect platter mat we now have.....(drum roll)......BUBBLE WRAP IS THE WINNER!!!!:rflmao:

Relax, I'm just kiddin' around here, but in all honesty when I first read that post, it was one of the things that jumped out at me while realizing you were attempting to find the correct height position of the record! My Nottingham Space Deck sounds best to me without any mat at all, but I'm sure we all have our own preferences on that score.

Meanwhile, I'm back to adjusting simply by ear once I get close to the 90deg. position, up and down a bit (with headphones as previously suggested) until it sounds best to me and I'm on to listening to music!

Happy holidays!
 
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