VPI JMW9 Tonearm setup questions


I just bought a VPI Aries Scout via mailorder, and am in the process of assembling it. I have some familiarity with setting up and adjusting cartridges and tonearms, BUT, I must admit that I am not familiar with unipivot tonearms.

I have no local dealer that has any VPI turntable set up, so I have not actually seen a JMW tonearm setup. I purchased the Scout based on the very positive comments here on Audiogon and elsewhere.

So, my question is really a basic one. The JMW9 Manual at page 4 states simply to "Place the arm tube assembly on the lower bearing." When I do that, the entire arm is balancing on the sharp pivot point of the lower bearing, but it is otherwise not secure in any respect.

Because the manual has no drawings or pictures showing what parts are to go where, I've been scratching my head wondering if I am missing a part of the bearing assembly that might slide over the sharp pivot point and takes up the space inside the cavity of the upper bearing housing. In fact, the nomenclature of "bearing housing" implies that this cavity is supposed to "house" a bearing, and there is nothing in there except the sharp pivot point.

Am I missing something here? Or is the tonearm supposed to float and wobble around touching absolutely nothing except the pivot point.

I hope this makes sense. Thanks for any guidance you can offer.

Coffee_nudge
Tad
coffee_nudge

Showing 4 responses by coffee_nudge

Thanks all for the responses. I just wanted to make sure that this is the way the tonearm is supposed to sit before starting in on the cartridge adjustments.

Coffee_nudge
ANOTHER remedial question:

The manual also indicated that tonearm height (VTA) can be adjusted with the "knurled knob" beneath the pivot. However, when I turn the know, it does not appear to do anything except move the knob itself up and down the threaded shaft.

The manual is not very helpful for a relative "newbie" like me. So what am I supposed to do with this knob, other than twirl it up and down the threaded shaft (no obscene comments please). Keep in mind this is the JMW9 -- I understand the 10 and 12 are somewhat different in the VTA adjustment mechanism.

I apologize for these elementary questions, and appreciate any and all help with this new (to me) tonearm design.
Okay. I am making progress here....got the tonearm and cartridge basically set up. I was running through the paces of the Hi Fi News Test LP, and ran into a brick wall when dealing with (you guessed it!) anti-skate. I realize this is a somewhat "controversial" issue with HW/VPI/JMWs.

I can get the cartridge to handle Track 6 (300hz +12db). But then I get a buzz from the right channel on Track 7 (300hz +14 db) and the arm just loses tracking on Track 8 (+16db). I did not even try Track 9 (+18db).

The results described above were achieved using the twist of the wire method suggested by VPI, with two full counterclockwise twists to increase anti-skate. I am reluctant to twist it any further, as I do not want to cause any damage to the wires.

Is this normal anti-skating performance for a JMW arm, or is there some method I should try, or is something else out of whack.

Thanks to all who have helped so far. Keep the info coming (please).

Tad

Let there be music!

I decided to quit fiddling with trying to adjust the anti-skating by the Hi Fi News LP, and just took HW's word from the JMW9 Manual that when the tonearm swings toward the edge of the LP when in a neutral balance, that's plenty of anti-skating.

Then I decided to listen to some LPs instead of test tones.

Oh Boy! Whether or not the anti-skating is correct, the music coming from this TT is quite nice....you know all the cliches....each instrument wrapped in its own blanket of air and occupying its own unique space, clean clear sound without tinny brightness (and the DV20X cartridge isn't even broken in yet), details coming out of blackness --brushstrokes on the cymbals, wider and deeper soundstage, etc. etc. etc.

In short, I am very pleased with this upgrade...I'll probably be able to live with if for a few months before upgrading again ;-)

Thanks again to all who offered advice and info. This forum is a great resource.