No it is not. In it's day the AR XA was a revelation. It blew away all those idler drive tables with it's suspension and belt drive. It's only major failing was a tonearm without an anti skate mechanism. In the day when Edgar Villchur designed it most arms did not have an anti skate mechanism. With todays cartridges an anti skate mechanism is mandatory. The XB did not remedy the problem and by then cartridges like the Shure V15 came along which could be ruined by that arm. It is extremely difficult to change arms on that table because the mass of the arm has to be identical or the suspension will not work properly. I'm sorry to report this, I'm afraid you got screwed. If $200 is the most you get stung for in this life you are incredibly lucky.
AR-XB. Is it worth a new motor?
I recently purchased an AR-XB for $200 from a gentleman who was selling it for an estate of the original owner. It looked great. I did everything but plug it in as he assured me it only needed a new belt. When I got home, the motor would not turn, although I could feel it humming under my finger. Unfortunately, I bought the tt in Pittsburgh while visiting my son. I hand carried it in its original box as a carry on back to Washington state. My question is, should I bite the bullet for a new $200 motor from Vinyl Nirvana, or chalk it up to experience and move on? Now I know some of you would spend more than that on the wiring for the tonearm, but that's a bit of money for my habit given my finances. The rest of the system is Mac 2100, Mac C26, Acoustat Spectra 1100, Audiolab 6000cdt, Audiolab M+DAC, MIT interconnects. Jazz, acoustic, bluegrass, Americana and vintage rock are what I listen to. Oh, and I have brandy new Ortofon Super OM 20 I was going to use. My back-up table is a Sony PS-LX5.