Graham Phantom B44 on a TW Acustic Raven AC1

Hi folks,

I�m requesting your help to fit a Graham Phantom B44 (9�) to a TW Acustic Raven AC1. I�ve bought both second hand and the TT comes with a blank brass arm base that needs to be drilled for the Graham.

I�ve got the 5 (1 + 4) holes diameter but not a clue about their positioning in the brass base. Ideally I would need, in order of preference:

- A drawing with the holes position that I could pass to the workshop that will mechanize the base
- A picture of a drilled base without the arm, so I could develop the drawing out of it
- Some positioning info, like distance of holes from base outer limits, distance between holes, etc

The four small holes position is crucial, because it will set the parallelism of the arm.

Any information about this will be gratefully received.

Thanks and regards

I can help. I installed my Phantom on an armboard I machined for a turntable I built.

Firstly, spindle to pivot = 217.5mm
Effective length = 235mm
Bob Graham gave me those numbers.

The mounting base I have is the Graham mount with 4 thru holes.
The 4 holes are located on a 2.200 inch bolt circle. I drilled and tapped 4 each 6-32 threaded holes and used stainless steel socket head cap screws.
Now I don't know how much rotation you will have with your armboard in order to orient the arm properly but the 4 holes on the Graham mount are basically 20 degrees of perpendicular.
The most important number is the 2.200 inch bolt circle, each hole 90 degrees apart on that bolt circle. Tell your machinist those numbers and you will have a nice fit.
I bored a 1.750 inch hole through for the arm base but you can get by with perhaps 1.500 inch, not positive on that.
Ask TW Acustic for the specs or have them do the armboard.
Contact Jeff Catalano at Highwater Sound. He is the exclusive importer/distributor of TW Acustic in the US. He often pairs up Phantom arms with the TW Acustic tables so he should know the specs for the arm board. Here is his info:

jeffrey catalano
high water sound, llc
274 water street 2f
new york, new york 10038
212.608.8841 T.
212.571.5809 F.
Hi guys,

When in trouble, it’s a relief belonging to this community. Thanks a lot for your comments.

Frank_sm: Very useful information, indeed. It is a step ahead in my search. I’ll try now to get exact arm orientation from AC users.

Downunder: Yes, your suggestion is the most logical, especially because I reside in Europe. I have reached Thomas Woschnick a couple of times. First one, I asked for mounting pattern. His reply was “the Phantom needs a center hole diameter 41 mm and 4 holes diameter 56mm 4 x 90° M4”. I’m sure this information is enough for an expert, but not for a novice like me… In fact, after Frank_sm reply I understand it much better. Still I don’t know how to position and orient the four holes in the brass base.

Therefore I sent a second mail asking him if he would do the drilling. That was on the 07-13-10 and I got no answer as yet. I understand he is a busy guy who travels a lot, and may be, the vacations ghost is striking here, so I’m trying to get more information to have it done by my myself. This beauty has been sitting on a table for several weeks now without producing any music and I’d like to have it up and running.

Cmalak: I didn’t think about it, but it is a good idea. As I imported the arm second hand from the US, Jeff Catalano was for sure the original distributor. If he has the information I need, I’m sure he will help me.

To any AC user: I understand that asking to unscrew the arm for taking pictures is a little bit risky with these delicate things, so I’m now asking for pictures with the arm mounted. While I try to progress in the official circles and wait for an answer, if someone having an AC with a Phantom would email me just two pictures, I might finalize the job without the uncertainty of “may be I’ll get a reply after August holidays”. The two pictures that would save my life are:

- One with a detail of the arm mounted on the brass base, in which I could see the four screws and the borders of the brass base at the same time. This would provide me with the right location and position of the holes.
- One in which I could see the whole brass base orientation in reference to the turntable. The fact that the brass base pivots at the other end doesn’t help here!

Both pictures should be taken from above.

Thanks a lot, guys.

Hi guys,

we have a happy end here. I contacted Jeff Catalano, as suggested by Cmalak, and he solved my doubts in one, simple e-mail. I'm copying it here for two reasons:

1- To share this info with anyone interested
2 - To show how good Jeff is. He got the keyword, novice, and sent me just the right instructions. Very impressive!

Thanks to all for your help. And hats off to Jeff of Highwater Sounds for his incredible service, especially taking into account that I did not buy anything from him.


The solution (Jeff's email):
Take the arm board and orient it so, the small mounting hole is at the top and thus, the area to be drilled would be at the bottom.
Or, small hole north, to be drilled south.
Measure from the southern most end up 44.45 mm.
That is the north/south point now, just find the center east west. Where the 2 points meet, that is where you drill the 41mm hole.

Now place the arm base with the 4 mounting holes centered over the 41mm hole and mark the 4 M4 holes so they are exactly 1 north south east and west.

There, you have it.