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

Hi Tom, the big problem is, that this will not work with a cartridge not fully broken in yet.......
Unless the cartridges suspension hasn't adapt to ambient conditions and hasn't reach its full velocity yet, the idea of the "WCA" won't give the right result.
Next problem is, that the cartridge designers won't supply any such thing.
It would force them to work even more precise and will give them no further USP if they incorporate such a "helping hand".
I guess most would fear that this would arise even more questions by the customer.
There have been designs in the past which did perform 100% right out of the box with very little to none variation in velocity.
Mainly cartridges designed and sold for broadcast (EMT, Ortofon SPU, Fidelity Research FR-7 series, Supex).
The better of these (FR, Supex) do feature a suspension which does keep its velocity from day one for over 30 years.
Todays cartridges - especially the Top-flight ones - do not feature any such thing.

In general setting the "right" "WCA" can be performed by looking through a highly illuminated magnifier from the front into the body of the cartridge and see, whether the cantilevers diameter is center in the yoke.
This however can't be seen on all cartridges - but on many.

But even this would only give a momentary result - changing in case the cart isn't broken-in yet.

There is no free lunch - it is still a game with a wide selection of important parameters which all need attention and skill to fine-tune.

If cartridge designers could agree upon strict mechanical parameters for all cartridges - that would make such optical settings much easier.

But so far we are left in the dark and have to trust our ears.....

"WCA"? Do we really need another acronym? What you appear to be talking about is finding the VTF (within the manufacturer's prescribed range) which will put the plane of the coil windings (basically the plane of the coil former) at a right angle to the lines of the magnetic force field generated between (or 'around', depending on the design of cartridge's magnetic generator) the magnetic pole(s). (In the case of MM cartridges, it's the reverse.)

The easiest way to determine this is to listen for or to measure (your ear will work just fine) the cartridge's maximum output at two or three nearby VTF settings (before making other adjustments.) Some tips: 1.) Do this with a mono record and (if it has one) your preamp set on 'mono'. Why? You may have harmonic distortion or minor tracking issues at this point before setting all the other parameters - but it's still important to set this one FIRST! 2.) If your cartridge is a new MC, delay all but a rough setup until after a minimum of 50 hours, AND for that first 50 hours, set the VTF to 1/4 gram OVER the manufacturer's recommended maximum. Why? First don't worry; you won't hurt the cartridge or the suspension running the VTF a bit high (and you should own an accurate digital scale by now ;-) This will result in a suspension (when break-in is over) with a 'Q' (elasticity factor) that remains constant just BEYOND the normal operating range -- otherwise, the 'Q' can be non-linear just at the point most MC cartridges yield their best output (the high end of the VTF range.)

After doing this, you can move on to setting the SRA and other alignment parameters; EXCEPT: forget VTA, which, if you give it a minute's thought, you'll realize is a totally useless concept. If everyone's cartridge's dimensions and angles (ALL of them!) happened to match EXACTLY all ALL of the cutter-head's dimensions and angles, there might be a case made -- and even then it would be philosophical at best, because you could only reliably play records made with THAT cutter-head/operator! And besides, lathe operators make adjustments too!! And cutter-heads generally are cantilever/suspension-less!

AND, if you have a stylus with a spherical or elliptical tip, you needn't worry too much because how it fits in the groove is pretty much the same over a range of SRA. A micro-ridge or line-contact stylus is just the opposite and SRA is extremely important. Here is the most accurate way to do it I've found to do it: Basically, you have to find the point (after finding/setting the optimum VTF) at which the stylus is perfectly vertical in the groove (looking from the side, not the front.) This is different for every cartridge (even among the same model/manufacturer.)

Once you've found that baseline, you can go from there. I've provided detailed instructions here: http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1140840022&openmine&zzNsgarch&4&5#Nsgarch
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Hi, D., your comments reflect the factors that I, too, believe (but don't ascribe to) will keep consumers from having an easily measured parameter for cartridge setup. My thoughts (rebuttals really) on the points against using WCA follow:

1) "...cartridges suspension hasn't adapt to ambient conditions and hasn't reach its full velocity yet, the idea of the "WCA" won't give the right result."

This is, in some ways, a mute point. Cartridge break-in, controversial as it may be, should not be a factor in alignment. My opinion is that we should just play records for some time before we seriously attempt to fine tune cartridge alignment.

2) "Next problem is, that the cartridge designers won't supply any such thing."

Probably not, at first. But I believe that cartridge manufacturers might be willing to provide this information for LOMC cartridges above a certain price point, say $750 to $1000 USD for example. It's in their best interest. If their cartridges are so good, why don't they publish the design parameters? Competition can be a good thing.

3) "...fear that this would arise even more questions by the customer."

Not necessarily a bad thing; assuming that WCA is only provided for audiophile cartridges (see #2 above), consumers would begin to ask why manufacturers are unwilling to provide WCA specifications. Audiophile cartridges are intended for a more knowledgable and experienced consumer. Again, competition can be a good thing.

4) "Todays cartridges - especially the Top-flight ones - do not feature any such thing."

And why not? If a manufacturer claims that their "top-flight" cartridges are so good, they should be more than willing to provide the specifications, including WCA, for their best cartridges. Manufacturers provide a range for VTF, why not for WCA? No shame in acknowledging the variability in suspension parameters.

5) "...setting the "right" "WCA" can be performed by looking through a highly illuminated magnifier from the front into the body of the cartridge..."

That's one of the biggest problems: The need to use high magnification and illumination in order to more accurately establish proper cartridge alignment. Many experts espouse the benefits of using these techniques to find the optimal alignment of SRA or VTA (impossible without x-ray vision). Much too complicated and inconvenient. WCA would allow a much more convenient parameter for consistent measurement and alignment.

And lastly...

"But so far we are left in the dark and have to trust our ears...."

That's the conundrum. Why should consumers be "left in the dark" in regards to optimal cartridge settings. If a customer is willing to spend a thousand dollars (USD) or more for a product that has a limited lifespan, the customer should be provided as much information as needed to get the most enjoyment out of the product without needless uncertainty and undue complications. Adjusting "by ear" is a poor reflection on the nature of cartridge installation. Most speaker manufacturers have much more objective parameters in setting up their product for optimal performance. And listening environments are far more variable than the plinth/tone arm/phono stage environment in which cartridges are installed.

Cartridge alignment should not be the mysterious endeavor that seems to be perpetuated by audiophiles and enforced by manufacturers. It needn't be so darned complicated. Using weighted cantilever angle (WCA) to find the (nearly) optimal alignment could make cartridge installation so much more convenient and consistent.

Tom

Hi, Nsgarch, the use of weighted cantilever angle would not add to the confusion but rather eliminate the use of SRA/VTA since both of these alignment parameters are nearly impossible to measure, especially VTA. Your description of how to find optimal SRA is, unfortunately, unrealisitic when considering the range of stylus geometries and the need for high magnification to actually see the stylus.

We actually agree on several aspects of cartridge alignment and your comments reinforce my belief that we need a more simple and easily measured parameter.

Tom

Tom -- finding true vertical for a line or micro-ridge stylus, as I outlined, is actually quite easy, and many people have done it with great results once it was explained. And there are only three stylus geometries, if what you mean by "geometries" is stylus 'shapes'. There are: spherical, elliptical, and line/micro. There was also the Shibata which was an attempt at making a line-contact but before laser cutting techniques were available. After finding zero SRA, it's nice but not mandatory, to have an arm with vertical height adjustment "on the fly" (while the record is playing) so you can experiment easily once you know where true vertical is for your stylus.

As for your statement

I refer to it as Weighted Cantilever Angle (WCA) which is the angle of the cantilever (from horizontal) where the manufacturer intended the cantilever to be positioned within the cartridge generator.

I think you are using the wrong terms, which is what's getting you into conceptual trouble. It's not the CANTILEVER which is positioned WITHIN the generator -- since the GENERATOR consists of the coil/armature positioned inside the magnetic field. The cantilever is completely outside that area. And frankly, I don't think cartridge makers are much concerned with cantilever angle, so long as it allows the cartridge body and front pole piece to clear the record surface. What cartridge makers ARE interested in doing is making the cantilever as SHORT as possible to eliminate resonances. The van den Hul Colibri doesn't even HAVE a front pole piece in order to facilitate an EXTREMELY SHORT cantilever. And DECCA cartridges have no cantilever whatsoever!

I truly wish people would stop using that "SRA/VTA" term as if they are the same thing -- THEY ARE NOT!! Further, VTA can be pretty much any angle between too low (the back of the cartridge hitting the record) and too high (the front of the cartridge or front pole piece hitting the record) and so what!? What IS important, is to let the VTA chip fall where it may, while instead MAKING SURE the stylus' edges slant forward at exactly the same angle as the forward-slanting groove undulations - thus locking them together.

Sorry for the long post but I'm afraid we have little to agree on at the moment ;-)

Neil
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