2. analog
  3. 1309722499

Graham Phantom II 12" - dimensions and overhang

Hello guys,

I come from Europe and recently purchased Graham Phantom II tonearm with 12" armwand.I was missing specs for 12" armwand (in manual are specs for 9" and 10"),so I emailed to Bob Graham and asked him for specs for 12" version. The answer was,that 12" version should be adjusted same as SME V 12". Bob sent me document with SME dimensions as well.

So regarding this document specs are Leff 308,8, overhang 13,2, mounting distance ( Pivot-Spindle) 295,6.
To adjust mounting distance is easy using any quality protractor. I used Acoustic Solid.

http://www.acoustic-solid.de/html/schablone.html

So with mounting distance adjusted to 295,6,here comes the thing.
I should set overhang to 13,2 regarding to specs for SME V 12",but simply
elko
suteetat
435 posts
 
I just got Graham 12" last month and there is no spec available. The manual is still for 9/10 inch arm only. It only said to look at addendum sheet for 12 inch spec but there is no addendum sheet anywhere in the box that I could find. So far I use only setup tool from Graham which seems to work ok but I am not really overwhelm by the result. I am thinking of trying mint protractor since it seems to really help both JWM 10.5 and Reed 3Q significantly.
sarcher30
596 posts
 
If you use an arc protractor like the Mint LP you will get the correct offset angle. As long as the arc protractor is designed for correct P2S for the arm you're using and you follow the alignment for zenith you will have the ideal offset angle. Just ignore the offset angle on the Graham 12" armwand as it is not correct.

Sean
sarcher30
596 posts
 
Suteetat, If your Reed 3Q is the 12" version then the Mint LP you have for that should work for the Graham 12" as well because they are the same P2S distance 295.6 mm.

Sean
syntax's avatar
syntax
2,193 posts
 
... far I use only setup tool from Graham which seems to work ok but I am not really overwhelm by the result

Of course it sounds awful because it is wrong, the alignment flip is calculated for the short Arm. But don't worry, that way it was in use at CES and all visitors/reviewers were floored :-)
Go for PtoS with 295,6mm and use a 12" Alignment System, Dennesen or similar, then you are spot on
suteetat
435 posts
 
Sean, thanks for the tip regarding Reed mint protractor and Graham. I did not realize that both has the same 295.6 PtS and 308.8 effective lenght. I checked briefly with Mint and was surprise as to the difference between Graham's own tool and Mint. I will try to set up carefully with Mint tonight and see. I also have Clearaudio protractor (as I understand, it is the same as Dennesen, I assume with IEC-standard R min 60.325mm, I still have not figure out this whole IEC standard r min thing and the manual is only in German). However, there seems to be no easy way to place the protractor accurately with the set PtS. It seems that Clearaudio and Mint are closer to each other than Graham's by quite a bit.
More to discover