Sansui CA 2000 preamp

Glad it fits into your system well! Especially regarding the low noise with sensitive speakers. 
A low powered amp would work well with them and a single ended tube amp might work well. At 100dB efficiency all you might need would be a 300B amp with typically around 7 watts. Which speakers are you running? What sort of volume do you play them at?
Class D amps are very efficient and put out lots of power for their size, but you possibly won’t need their high power in this case.

I have a CA 2000, a AU666 (running as the amp with the CA 2000) and a TU666. All are running on their original capacitors will no problems. 
The components are all very high quality with a long life. I firmly believe in leaving these devices alone. If it sounds good it is good. If it started to sound crappy and it was not switch related. I would have it serviced. The one issue I have experienced is noisy switches and rotary dials. These are tricky to clean, as it is hard to access these without completely removing them. On the whole, modern quality audio components benefit from all the technical advances made since the 70's. Still I use these because I love the sound and the look. The same reason why I run an old Sony 557ESD CD player. Looks and quality.    

linn9000,

I have no doubt your equipment is still working fine and still sound great, my experience shows otherwise though.  Caps in those older models are getting on in years and will eventually fail, probably already drifted off spec as well. really when your getting into 30+ year old electronics its just a mater of time before something goes and when that cheep cap or resistor goes and takes your transformer with it (been there done that) expensive, hard to find (usually) and rarely new. I've refreshed a few vintage pieces now and everyone sounded way better afterwards. CA 2000. TU717, Treo 100, Dynaco Mk4 Mono's, so far and everyone was much improved.  

I had one for years.  Should sound glorious!  Listen to it, then decide if it needs a recap. You know it does if it sounds dead, otherwise leave it alone.
Enjoy!
N. 

I've been running it all refreshed for the better part of this year and its quite surprisingly good. I've driven Dynaco Mk4 mono blocks (also moded),  Audio Note Quest's ( borrowed for a month while i was considering buying them), Finale Audio 300b amp and a surprisingly good little  Burson Bang (22wpc) that little guys is quite detailed and extended and drives the horns very well, almost better then some of the tube amps I've tried. 105db speakers mind you.

 I expected the old Sansui to be overly warm and well vintage sounding and its far from that.  I'd say its very neutral  (with the tone bypass engaged) and the volume control is so smooth and responsive. Its really nice having more then a couple inputs and two sets of switchable (1,1+2, 2) outputs.  I really like many of the features these older preamps offer that the newer ones have dumped decades ago. obviously when you use many of them it degrades the sound slightly but fortunately you can bypass it all. 

over all I'm quite happy with the sound. yes there's better but from what I've heard in comparisons you need to spend many $thousands and lose all/most of the features. Only thing I'd like is a remote but I can live without it. 

 I've been pulling back from the supper high end and exploring vintage and obscure gear. As my hearing degrades as I age (55) and from my tinnitus I don't see the need to chase the never ending quest for ultimate sound that in my experience just ends up being too detailed, too in your face and no musicality.

there's a point when a Ferrari is just a car and your paying for a name and bling nothing really more.  Same goes for audio equipment some are willing to pay for the name and bling I've moved passed that in my music quest and just want to enjoy the music with out  evaluating the sound quality all the time.