SME 3009 S2 Improved Collar/Bayonet

[Barry]

I think he means that it's not compatible with the II Improved. The R versions have the fixing screw in a different location.

I didn't know about the different location of the screw for the R version (I'll have to have a look on mine), but I think the location is the same for both the II (non-Improved) and the II (Improved). I have samples of both, so again will have to check.

I could understand if AudioSilente distinguished between the Mk. I and Mk. II arms, as the Mark I used a stainless steel arm tube with (perhaps) a different bore diameter.

[Shovel_Knight]

I think he means it's incompatible with the fixed headshell version (II Improved) and not the S2 Improved which has a removable headshell.

[dantheman91]

Update

Removed the screw for holding the collar in adjusted god they are a pain to get back in and the head shell slotted in and screwed no problem the azimuth problem is now fixed to and staying in position -

Happy Listening The SL 150 needs speed adjustment

[Barry]

Update

Removed the screw for holding the collar in adjusted god they are a pain to get back in and the head shell slotted in and screwed no problem the azimuth problem is now fixed to and staying in position -

Happy Listening The SL 150 needs speed adjustment

That's good news Dan.

I have never had to remove the screw completely, in fact on one of my SME arms I had to tighten it, as the headshell could rotate slightly in an anticlockwise sense when the arm was lifted out from the arm rest. Adjusting the screw with the arm in situ is tricky: you need a very short screwdriver, but it can be done.

The screw has been described as "stupid", but I can't see how one can provide azimuth adjustment without providing a means of locking the collar in place once the correct azimuth setting has been achieved.

[Shovel_Knight]

The screw is necessary to keep the headshell socket in place, that much is obvious.

It's the whole idea of a friction fit headshell socket that can be rotated to adjust azimuth that I have an issue with. The socket is a tight fit which makes precise and repeatable azimuth adjustment difficult. However, at the same time it's not tight enough and it's possible to slightly disturb it when changing headshells.

The best implementation of adjustable azimuth I have seen was designed by Micro Seiki. The end of the armtube is slotted and there is a clamp that can be loosened for easy and precise azimuth adjustment; but when it's tightened, the connection is absolutely rock solid with no accidental adjustment possible.

[Barry]

The installation instructions for the SME 3009 arms changed over time. Early versions relied on the collar/connector being a tight friction fit to the arm tube and the screw was not touched at all during azimuth adjustment (steps 123 and 124 on page 10 of: https://sme.co.uk/audio/wp-content/u...CTION_BOOK.pdf)

Later versions required the screw to be slackened before azimuth adjustment and tightened afterwards: steps 1237 to 1239 on page 16 of: https://www.theanalogdept.com/images...odelsRtype.pdf

This would suggest the head diameter of the screw might have been changed on later models, so it didn't sit within the slot but could 'nip' the sides of the slot.

Yet on all of my SME arms: Series II and Series II (Improved), where I have had problems with the headshell collar/connector rotating, all I needed to do was to tighten the screw.