Best mid priced Amp-Preamp

NAD - worth trying their little digital integrateds.

Rogue Sphinx hybrid integrated, 100 watts/ch.  $1400

Schiit Freya pre, Vincent SP-331 amp. They sound wonderful together.

Tom

I'll check them. Thanks for quick your response.

Used Rogue Cronus Magnum II integrated can be obtained under 2K$.

It has musical midrange and powerful bass

On this site there is a Hegel H160 integrated and a Belles Aria Integrated.  Either of these will be noticeably better than your old Adcoms. 
If you want less $$$ there are another half dozen solid contenders,  but these 2 are excellent.  

The above are all fine.  I use to favor heavier Adcom products.  Adcoms can take bad treatment, abuse of all kinds, and keep rocking.Maybe a good replacement would be Adcom 555...Less than $1k.

I didn’t look up your speakers. But with as little as $2300, the best bang for your buck that I can think of quickly is all Schiit: Freya Preamp and two Vidars run as monoblocks. That is plenty of power with a bunch of overhead. That is $2100 with $200 for delivery fees. I have had Vidars and they put out plenty of nice power. Better with efficient speakers though. I have a Freya and it really is great and great for the money. 

I had an Adcom GFA555 and GTP500. Needed work...

Replace them with current tech (digital included). I found a deal on the Peachtree nova300 for $1800. Bought some Ascend Acoustics CBM170S,$330 (and a used 8" sub). They will work till I can
 go around the country listening to better open speakers.

You may want to consider the Rotel integrated amps, the RA-1572 (around $1,699 new) or the newer more powerful RA-1592 (around $2,499 new).  The former is 120w/ch, the latter 200w/ch and each comes with a very nice DAC chip.  I own an older Rotel receiver and can speak to its durability and quality of build (like your Adcom products).  Each can be found used on Audiogon.

+1 on the Hegel H160. Also look @ Peachtree and Schitt. 

kns54 OP
  Please suggest best amp-preamp under $2000 for my KEF 103/3 reference series speakers.

A little more but this new John Curl designed Halo Integrated just got good raps put on it, not quite as as powerful as the older one which you could get on your budget, has everything even a Sabre dac in it. And would love your speakers.
JA's bech tests yet to come.
https://www.stereophile.com/content/parasound-halo-hint-6-integrated-amplifier

Cheers George

+1 with tomcarr,
The Freya preamp is pretty darn good for the cost and it leaves you enough for a Vincent, Adcom or Schitt amps/amps.

All the best.

JD

kns54 OP

I’d go along with that too curiousjim , a Schiit Freya (great switchable tube/ss/ or passive preamp) with a Schiit 100w Vidar. Should work a treat with the KEF 103/3, and at 93db maybe the Schiit Aegir 25w class-a if he doesn't want party levels, that would sound sooooooo sweet.
And the OP kns54 can trial them for 15 days

https://www.schiit.com/products/freya

https://www.schiit.com/products/vidar

https://www.schiit.com/products/aegir

Cheers George

Marantz pm14s1 integrated, if you can still buy one, getting hard to find brand new. A second for the rogue sphinx v2...on the more economical side, the new marantz pm8006 is a nice amp as well at only 1200.

Underwood HIFI is selling brand new (NOS) Peachtree Nova 220SE integrateds for $999. I used one for 2 years on a pair of LS 50's and enjoyed it immensely. I also like the Rogue Audio Sphinx (any generation).

Thank you all for your suggestions. I decided to go with Rogue Sphinx v2.
Thank you again!

Good choice!!!

not completely neutral but GOOD!

That’s a very un-Rotel sonic description, haven’t heard this one but many others, and I find them very neutral but a touch sterile.

Cheers George

Great choice! I think you will love it...