Looking for ACCURATE SPEED turntable/tonearm combo

Like it or not, you are not going to get the speed accuracy of a Technics DD until you move up to about the $5000 range. Why not the Technics? They're dead-nuts accurate on speed. They are also very quiet, in spite of what the shills for the British cottage turntable industry say.

The Technics has a very sophisticated speed control, but not much in the way of isolation. If you're budgeting $1500-2000, you can easily get an SL1200 plus outboard PSU plus Origin Live armboard and Origin Live fully-modded OL-1 ($800) or Silver ($1095) tonearm. Add Isonoe or Mapleshade Threaded Heavyfeet set on a nice thick butcher block or maple plank supported by sorbothane, cork/rubber, or gel pads and you're there.

I can definitely recommend the Rega P5, with the separate power supply, which helps to keep that speed accurate, also Nottingham makes some fine tables in that price range. You can do much better than the Project tables for that money.

new dual 405 or 505...or denon

I'll echo what Mard51 and Johnnyb53 posted.

Buying on a budget means choosing between compromises. If speed accuracy/stability is primary then no inexpensive (< $4K) belt drive will provide what you seek. The brand doesn't matter. They're all audibly compromised when it comes to maintaining speed through musical transients because they all use elastic (stretchy) belts. When the stylus hits a big transient the belt stretches and the platter slows for some brief instant. Once the transient peak has passed the belt rebounds toward its original (shorter) length, speeding the platter back up again. If you're very sensitive to pitch variation this effect is audible - every time. It's more audible when such a table is A/B'd with a more speed stable design.

A good source would be the modded Technics 1200 tables from KAB USA.

Take a look at the Galibier Serac. It's above your budget, but it's the lowest price table I know of that begins to do both speed stability and resonance control at high end levels.

Another Technics convert here...

Look I left vinyl back in 1987 you know 'perfect sound forever' came back in 2003 but the snobbery of many vinylphiles steered me away from direct drives and I stupidly did not look into either a Technics Sl-12xx mkII series or a high end vintage unit. I bought a Music Hall mmf2.1 which was a very nice lil table. It was not pretentious and it did reignite my love for vinyl. From there I built two DIY belt drive table and they were fun and had decently good sound. But none had the speed control and the PraT I in the end knew I was missing. I bought a KAB USA modified SL-1200mkII with Cardas arm rewire. and it is simply a killer table in its price range and even vs higher up tables. If you want a sub $20,000 turntable which has rock steady speed stability and w&f figures that are INAUDIBLE then you really must consider among other table you are looking at a Technics SL-12xxMKII.