Hi: This is prob an easy question to many, but it’s always intrigued me. I presently have a turntable with an “S” shape tonearm. I have several cartridges mounted on headshells which I use pending type of music etc. Of course mounted as such saves time when I want to go to a different cartridge. If I were to purchase a turntable with a straight tonearm, I suppose I will have to remove the cartridges from the present headshells and replace them with those designed for straight arms. I believe this is due to the different angle in which the stylus rides in the groves. Am I correct? If so, is it possible to arrive at that angle by adjusting the cartridge in the present headshell. thanks in advance.
The cartridge angle and offset is the same, regardless of whether the arm tube is straight or curved, it is based solely on the pivot to spindle distance and which alignment geometry you elect to use. The cartridge on an s-shaped tonearm will only be aligned straight in the headshell if you stay with the manufacturer's chosen alignment. Other alignments will cause it to be angled slightly. Most straight tonearms don't have removable headshells, the best (in my view) use a fixed headshell firmly attached to the arm tube and provide azimuth adjustment back at the pivot. That way, the typical joint flex in the headshell to arm tube connection can be avoided. But there are some old and new straight tonearms that do have removable headshells, or even removable arm tubes, so that is an option too. Sometimes they are proprietary, though.
The S arms you mention do often have removable headshells, so you can swap them in and out. Most straight tonearms (e.g. Rega RB300) do not have removable headshells: you fix the cartridge directly to the tonearm. Thus, you’ll have to remove the cartridge from your existing head shell and re-install it. Straight arms also require different alignment; you can buy a special alignment tool or print one from the internet, and there are tons of tutorials on this forum or YouTube for how to use them. Good luck!
Some vintage straight arms had removable head shells. All I have seen have the angle built into the shell instead of the arm. They will not work on a curved arm. My old Yamaha table even uses a proprietary mounting design.
Correct, but finding multiple headshells for any straight arm is going to be a challenge since they were never standardized like the straight shells for curved arms.
I have an old Sony direct drive straight arm with a removable headshell. They’re very difficult to find, and I’ve even seen them selling for more than the entire turntable itself
So, each cartridge must be individually attached to the headshell portion of the strait tonearm. thanks to all who responded.
Straight arms came into being as a way to go low mass. Some early ones had a removable shoe that slid under the head, but for the most part, you give up interchangeability when the arm is straight. (Thorens uses a removable ‘wand’ that is about 1/2 the length of the tonearm, but today, that is more for installing the cart as there are no longer replacement wands available. The Schopper wands on eBay from Switzerland are not the same low mass as Thorens and you wind up with a heavier arm.) The removable mechanisms simply added too much mass defeating their design goal of a straight arm. I you took two arms with identical pivot to spindle distances, one an S, and the other straight, and laid them a top each other so their pivot points aligned, where the carts end up will also align for any given alignment.