Alignment Snafu? Or?

Hello Narrod/All.
Thanks for the info so far.
The info I have downloaded, and know so far, is a claim of the AQ PT-6 through PT-9 on Vinyl Engine of an effective length of 229mm, mounting distance of 211mm, overhang 18mm. All show null points (Baerwald) at 66.0mm-121.0mm

As has been explained to me, some of these arms were indeed like you say, mounted at 210mm, and perhaps the specific reason, was that one wouldn't run out of Headshell Slots, wouldn't need the Cartridge mounted so far to the end of Slot travel, and have the Cartridge more centrally mounted in the Slots? Just a thought?

To achieve Baerwald alignment with my Turntable Basics Mirror Protractor, and ZYX Airy 3X, I'm just about at the end of the Slot's travel, but can achieve what appears to be dead on alignment with the TB Protractor.

It was like this as well with my Benz Glider, and in fact my previous Benz Glider literally fell apart last year in my hands in two pieces trying to shift it forward far enough when I used the TB Protractor. The Body seperated from the Base, and with it went the Pin Wiring, and Suspension Wire! One drop of Adhesive was all that held the two together, and after 10-11 years, maybe that Adhesive had gotten slightly weak? I didn't apply too much pressure, but was probably trying to shift the Cartridge forward where it just couldn't go due to running out of Slot on the Headshell.

Perhaps, VPI when they drilled the Plinth 12 years ago, did so every so slightly too far? Mark

Try the Stevenson geometry. It may give you more flexibility with alignment. I have VPI HW-19 and Audioquest arm and find it difficult to optimize setup with Baerwald. I haven't tried Lofgren.

Thank You Narrod, Another person has advised me exactly as you have, to perhaps trying Stevenson Geometry.

While my rig is sounding pretty darn good, I think all can sympathise, trying to squeeze every last bit of performance from my vinyl rig. My ZYX Airy 3X is still very young in age, certainly doesn't have sufficient break-in time on it yet, but sounds better, and better each time I play it.

I have been able to achieve dead on alignment with the TB protractor, and yet wonder, with these sight line protractors, and even though I've noted a 1mm error on mounting distance, is alignment still correct? I've used the outer grid to align, have aligned the stylus, and cantilever, not the body, and haven't concerned myself too much with the inner grid on the protractor.

I do get somewhat confused with protractor geometry (wasn"t the sharpest crayon in the box in match class) but gather that regardless of mounting distance, sighting with the sight line protractor "should" net me correct alignment?

If I am incorrect about this, I am hopeing somebody will correct my wrong assumptions. Thank you, Mark

Mark, I think that from your description of the issue you may just have to live with a small amount of error in the setup. In reality, we all do. The only thing we may be fortunate enough to do is limit that error more in one setup than some other setups. But it has been published in several places that an error of less than .5 mm is almost a necessity to get the most from a particular arm/cartridge. This doesn't mean that you won't still enjoy what you hear. Perhaps this is something to keep in mind if you ever go looking for a table upgrade.

Hi Mark,

Dan alludes to the active thread here:
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1210959908&read&3&4& where you'll find several informative links.

Read this stuff and then read it again. Know that using a sight line introduces more error than it attempts to correct. I'm not arguing that you can't get "lucky" using a sight line, but we want to eliminate luck from the equation and introduce repeatability.

May I humbly comment that you don't know how good your setup can sound, and won't know until you set it up with an arc-style protractor which agrees with the pivot to spindle distance of your rig?

Know that you want to take your best shot at having a protractor to match your current pivot to spindle distance - as long as you have enough room in your headshell slots to accommodate corresponding effective length and offset angle changes.

So, if your actual p-s is 210, that's fine, as is 212. It's more important to know the distance as precisely as you can measure it. This assumes two things: (1) that you have headshell slots long enough to accommodate the new tonearm parameters, and (2) that if you mount the arm on another turntable that you replicate your current pivot to spindle distance.

Remember, the only down side of an arc style protractor is the effort you need to put into getting the pivot to spindle distance to agree with the protractor you've specified. The up side is huge however and worth the effort.

Unless you're using something like the trammel portion of a Feikert protractor, you will unlikely be able to measure your pivot to spindle distance to within .5mm.

So, try the following before you do anything else: loosen your tonearm mounting screws to see how much play you have - the ability to make fine adjustments to your pivot to spindle distance. You will likely find that you can get +/- at least .5 mm and perhaps more.

IIRC, your AQ arm mounts like a Linn, with three holes that fix a base plate in place. Know that you can enlarge these 3 holes (as well as the arm stub hole if necessary) slightly to get further fine adjustment of your pivot to spindle distance. Just remember to measure twice, and drill once.

No matter how you specify your protractor, you'll want to know what you're up against from a p-s distance perspective anyway, so you might as well know now rather than later.

Be prepared for a revelation when you get everything right.

Cheers,
Thom @ Galibier