An easier way to set VTF/VTA/SRA? Perhaps....

Neil, thanks for the explanation. And for being tolerant of my misunderstanding of the relationship of the cantilever and generator. (The few schematics I've been able to find are crude representations at best.)

My original thought on the use of cantilever angle had more to do with setting proper stylus rake angle, as installed by the manufacturer. Using SRA as a measurement parameter is possible but not easily measured. Your procedure is certainly an improvement but still requires more effort than many vinyl lovers are willing to undertake. I wanted something quick and easy. :-)

In considering the use of cantilever angle, I assume that the stylus is properly mounted to the cantilever and that the manufacturer knows the angle of the cantilever when the stylus is at an optimal rake angle. Wouldn't it be much easier to measure the angle of the cantilever rather than a tiny stylus? (The exceptions you mention, notwithstanding.) If the process of mounting the stylus to the cantilever is not consistent and the resulting placement is so variable that determining proper SRA is not possible using WCA then this whole idea is a lost cause.

Tom

PS: We may agree on one thing: VTA is a fairly useless parameter. '-) I only included it as part of the collective theme of cartridge alignment.

Well, the cartridge manufacturers do already provide the parameter to set the VTF right: - their recommendation of the range the VTF have to be set in.

We will get no more and there is good reason why.
Aside that there is no monetary reason for the cartridge manufacturer to add any mechanical "helpers" - there too is little need.
Analog cartridges for the high-end customer is a luxury market with highly emotional customers. Nothing to quantify - nothing to determine the quality with any measurable parameters.
Similar to high-priced jewelry (at least there are quantifications like purity of precious metal, carat etc.), high performance cars - you name it.
Its individually viewed AND judged performance and personal preferences.

I guess - as frustrating as this might look on first sight to some - that we are doing quite well the way it is now.
Unfortunately this means that setting up an individual analog cartridge to fully show its abilities will always require skill, knowledge, experience and very precise handwork.

But then most of these are needed in all real passions.

There is hardly ever any free lunch out there.

Cheers,
D.

We all agree that a cartridge usually needs some time to reach its designed for operating conditions (velocity). Furthermore we are looking at a bundle of other depending parameters (tonearm, cable, matching impedances, inductances etc.) in interaction with the cartridge and thus influencing its sonic performance.
Next in line is individual sample differences within a production design.
No two cartridges of a given production design are truly identical in the technical sense nor in their technical parameters.
After all most are hand-trimmed or fine-tuned and so they are similar and go for a similar "family"-sound, but are not identical.

We will always need a range to work within.

I wish I could agree with more of what everyone is saying, but most of it is wishful thinking. For instance

I assume that the stylus is properly mounted to the cantilever and that the manufacturer knows the angle of the cantilever when the stylus is at an optimal rake angle. Wouldn't it be much easier to measure the angle of the cantilever rather than a tiny stylus?

All I can say is I wish it were true but it's not. It's hard enough to mount a stylus to a cantilever. Expecting to mount the diamond at the same angle to the cantilever time after time is simply not possible. Even the solid one-piece diamond stylus/cantilever cannot be fabricated identically time after time. Thus the need for calibrating the initial zero SRA point for each stylus-cantilever assembly. Thaough statistically possible, no two can ever be assumed to be the same. As for

Well, the cartridge manufacturers do already provide the parameter to set the VTF right: - their recommendation of the range the VTF have to be set in.

There's a reason for specifying a 'range' and it's this: there is only one VTF setting for an individual cartridge at which the suspension will compress just the right amount to place the coils at exactly 90 deg. to the magnetic force field. If you look at a mechanical drawing or exploded view of a typical MC cartridge, there is a tension wire attached to the coil armature on the opposite (back) side from where the cantilever is attached. This wire is carefully pulled to a certain tension and locked with a set screw. This "pre-compresses" the suspension rubber; otherwise applying the correct VTF would just collapse the suspension and the cantilever would 'retract' up into the cartridge body ;-) Further, that wire is not pulled straight back, but slightly upward and back, forcing the coil armature to sort of 'tilt' forward and putting a little "downward English" on the cantilever - then, when the stylus contacts the record at the 'perfect' VTF, the suspension compresses and the coil armature tilts backward slightly, bringing it into proper right angle relationship to the force field. It's the trickiest of all the steps in making a cartridge and each cartridge will have a specific VTF setting (within its specified VTF range) where that alignment is correct. As far as I'm concerned, each cartridge has one absolute VTF setting at which this perfect alignment occurs. (It also happens to be the one where the cartridge sounds its best ;-) The SRA setting is not absolute. It will vary +/- a half a degree from the average 1.4 degrees as a result of two factors out of our control: record thickness and the whims of the lathe operator. Which is why SRA on the fly tonearms are preferable. And why I'll either eventually sell my SME V or get so old I just don't give a rat's a-- anymore!

Then you have to get the other geometries right on the money. Overhang, offset angle, azimuth. The only setup parameter that will usually vary (SLIGHTLY) from the theoretical ideal, and therefore a bit open to musical "taste" is cartridge loading. That variability is due to differences in tonearm mass/damping, cables, phono preamps and/or SUT's, or other room and/or hardware factors. It's where you get to tailor (if only slightly) the sound of your cartridge to suit your sonic preferences.

The other settings are pretty much absolute if you take the time to discover them. One can't (or shouldn't!) just go and "de-tune" a cartridge in an effort to change its sound ;-). You can try fooling with loading, cables, pre-preamp equipment, even different tonearms; but finally, if you don't dig the sound, it's just not the cartridge for you.
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Excellent, Neil! One of the better descriptions of the construction and workings of a moving coil cartridge that I've read. And to you and D: Now I understand that the idea of using WCA is truely "wishful thinking".

Guess I'll have to make the investment in a quality magnifying scope and spot lighting in order to more accurately set SRA. I have extraordinary near vision and can see the stylus angle fairly well, but it makes sense to start from a known setting.

However, the relationship of SRA to VTF and optimal coil position makes the whole vertical alignment process a bit of a "chasing-your-tail" scenario. Set for SRA and then fine-tune VTF for optimal coil position (best sound); but then you may have altered SRA. Reset SRA; but then you may have altered the coil position and have to fine-tune VTF again. And on it goes.

I was hoping for an easier way to find the vertical alignment sweet spot. I wish. :-)

Tom

Tom, you have the sequence reversed. There should be no tail-chasing ;-) ! You first MUST wait 50 hours (100 if you can stand it) until the suspension is settled in; a term I prefer to broken(!?) in ;-)

And forget some manufacturers' claims (like Immutable Music who made my Transfiguration for instance) about their new "space-age" suspension elastics. Maybe they ARE less susceptible to deterioration, however, there are NO supensions/cartridges that I've so far used, or more broadly, heard about or read about from their users, that didn't change quite audibly after the first 50 - 100 hours. Which is another reason why running-in a new cartridge at .25 grams OVER the max. recommended VTF (as I described earlier) for the first 50 - 100 hours is IMO essential for the long term stability of all other settings, including SRA.

The sequence I recommend (to avoid tail-chasing) is:

1.) Install your new cartridge in the TA and make the various geometrical settings as reasonably accurate as possible without being obsessive about it (there will be plenty of time for obsession later on ;-)

2.) Set the VTF to .25 grams over the max. recommended, for the first 100 hours.

3.) Play records for 100 hours. You don't HAVE to listen to them, but definitely play them. I emphasize that because some folks think you can "season" a suspension by just leaving the stylus/arm/cartridge sitting on a record for 100 hours without the platter revolving. I don't know about that one, but it just doesn't feel right to me!

4.) After the initial 100 hours, re-set the VTF for the loudest output. Let the high frequencies be your guide for "loudest", because they are the first to disappear when the coil isn't in the perfect position. You may have to do a few trials before you can decide. Use a mono record as I described earlier. That setting should be good for a long, long, time.

5.) Set the SRA as I described elsewhere.

6.) Level the platter using a small spirit level. Check with the level oriented in opposite directins. Average if you have a crappy level. Then, make sure the headshell is level along the spindle-to-stylus line.

7.) Set the azimuth (if your headshell or tonearm tube allows) using the mono record technique.

8.) Check stylus overhang and cartridge off-set settings from Step 1. But FIRST, note your VTF, because if the overhang needs more than 1 mm adjustment fore or aft, you'll need to reset the VTF to what it was before you reset the overhang.

9.) Set the anti-skate to ,3 to .5 times the VTF as a start. Line contact styli produce so little frictioon in the groove that using any anti-skate is probably gratuitous as far as differences in sonics is concerned -- but it does tame the TA skidding toward the spindle at the mopst inopportune moments!

10.) Set the loading (for MC cartridges) starting at 15 times the cartridge's internal impedance, and raising it slowly until the bass 'tightens up', but before it diminishes any amount in volume; and before the treble gets glaring (the bass will usually go first though.) If your phono preamp has only fixed load settings, 100 ohms will usually work very well for most MC's.

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