Alignment Snafu? Or?


Hello all, I am about to order another Protractor, this one an Arc Type from Ken Willis over at the Asylum.

Ken has asked if my arm was at 210mm, or 211mm Spindle-Pivot Distance, and taking an actual measurement this evening, I actually find out my arm is mounted at 212mm. So, may I ask what should he make this Protractor for, 212mm? Or no? Will 1mm make a critical difference in accuracy, and sound? I will forward this info to him as well, and see what he says. More input, and advice is of course better. Thanks, Mark
markd51
Hello Thom, Thank you too for your comments, and support, your experience has helped me.

With my AQ PT-8 Arm, I am currently using a Pete Riggle VTAF, and as you probably know, the VTAF Bushing in essence replaces the Arm Mounting Base.

My Table is still essentially a HW-19jr, (But with 16lb MK-IV Platter/Bearing) with the stock one Piece MDF Plinth, and I had kicked around the idea over the past few months of replacing this Plinth with either a machined, solid 1" thick Aluminum Plinth, or 1" thick Black Acrylic Plinth.

Haven't yet decided if I'll ever do this, but having one friend who's a master machinist, constructing a 1" Alu Plinth wouldn't be a problem for him, and getting the precise P-S distance to whatever I choose.

Not sure how Aluminum would sound, but at about 18"x21", and 1" thick, estimated weight he claims would be close to about 25lbs. In this scenario, I could have the Plinth Polished-Black Anodized as well.
Cost is not cheap, but perhaps not as expensive as one would think. Sheet of Alu Stock would be about $100 shipped, and about another $100-$150 for machining, and Anodizing.

No doubt the stock Sorbo Suspension would be taxed, and another method-type of suspension would have to be implemented as well. Mark
Hi Mark,

One thing I've learned is that you can never predict the results of any change you're going to make. The changes need to be considered in the context of your complete analog ecosystem.

For example, yours (VPI in general) is one of the only cases where I've seen Sorbothene contriubite positively to the sound of a turntable. There may well be others, but I have not encountered them.

I'd be inclined to try to perform a root cause analyisis on what you like about the Sorbo - even if it's only empriically done (e.g. trying other stuff).

I'm wondering if you're responding positively to sorbothene's damping properties, or to the fact that it's sticky and holds thing in place. If you are able to answer this question, you might be able to take things to the next level (or not ... no guarantees in this blood sport).

If you decide to give aluminum a whirl, have your buddy get a quote on pricing before ordering.

Everything we buy these days is so dependent on fuel costs and prices jump around like soy beans futures these days (although in general, trending sharply upward).

Cheers,
Thom @ Galibier
Mark,

Another suggestion: try installing your cartridge without the finger lift. The extra hardware and material boundaries make your cartridge less stable in the headshell and alter the resonance behavior of the cart/arm. I can't guarantee this ecology change (as Thom put it) will be an improvement, but I can guarantee you'll hear some differences. I'd bet in favor of leaving the lift off, but you can be the judge of that when you listen.

Doug
Hello Doug, thank you for chiming in, and it's good to see you back here posting some!

Was I'm sure hard for some of us folks "holding up the fort" so to speak, in your absence!

I will probably do as you wisely suggest, and remove, and put away the little Arm lift, as you once suggested to me to do many months ago. When Ken ships the new protractor, and I again check all parameters, and I will at that time remove the finger lift for good.

As you mentioned to me once, Frank Shroder leaves em off a $6K Arm, and there may be very good reason, due to sonic detriment, rather than also the obvious mechanical one that I had an issue with.

I'm generally not a guy who constantly lifts an Arm from track to track anymore, preferring to let an entire side play through. Thanks Doug/All Mark
Hello

I just purchased a wally tractor universal. On it is an arc for rega arms with an effective length of 239 mm. I have an origin live arm, the OL specs are spindle to pivot distance 223 mm and overhang 17.24 mm, effective length 240 mm. Being a newby do I then shoot for a spindle to pivot distance of 222 mm and use the 239 mm arc or aim for 223 mm P-S and use the 239 mm or another (241mm) arc?

Thanks