Which headshell to use?


Hello. I am a new member to Audiogon and am seeking some adivce. I have a vintage system consisting of a Pioneer SX1980 receiver, Teac X2000 reel to reel, Klipsch Belle's and most recently added a Pioneer Series20 Model PLC-590 turntable. It is set up with the Pioneer PA1000 tonearm, but has an aftermarket headshell by Audioquest. Ive installed an Audio Technica 440ML cartridge that I was previously using on my Empire 698. Given that you guys know just about everything with regard to turntable setup and I know just enough to get myself in trouble, could someone please reccommend an appropriate headshell. Any feedback will be greatly appreciated. Looking forward to becoming part of your community. Rick
35off
Thanks for that bit of info Mofi. That's a biggie! I acquired this TT from a friend of mine who owns a high end stereo store here in Jacksonville Beach. They were doing close to a 200k install and took a bunch of gear from their client on trade. This Series20 TT was part of that gear. Being a vintage Pioneer guy, I grabbed it up right away. It was an easy replacement for the Empire 698 I was running. It fits in nicely with my SX1980 and in my opinion a big improvement over the Empire. I probably should swing back in and see what else they brought in from this guy. So thanks again Mofi, I really appreciate the input I've received from you and everyone on this thread.
About Audio-Technica headshell with fixed screw holes:
Yes there are no slots to move cartridge in headshell but on the backside of the AT Technicard or Magnesium headshell you will find at least two sets of mounting holes. The most important thing about this type of AT shells is FULLY ADJUSTABLE OVERHANG AND AZYMUTH and with thus option you don't need any slots, you move the whole shell to adjust cartridge with your protractor!

Just a note: not all AT magnesium headshells are adjustable. The mg 10 is not. I learned this the hard way.

Sumiko HS 12,Adjustable Azimuth,Litz wire, Needle Doctor sells it for $90.00.
Yogiboy,

LP Gear sells the same Sumiko but calls it Zupreme. They only ask $55 for it! BTW. Jelco also sells the same head shell but lists it under their name!

Regards,
We're talking about any headshells or about very good headshells ?
Does it improve the sound when you change just a headshell ?
Dual pin Zyx Live 18 DOES (pretty much) more than any other headshells i have tried on my EPA-100 tonearm.

P.S. SAEC ULS-3X ALSO RATED VERY HIGH (AND THE PRICE TOO), anyone happy with SAEC ULS-3X? I've never tried it myself.