Vintage integrated Amps. What to look for?

I have always liked the Kenwood KA-6100,7100,8100 & 9100 models,
The design of the cosmetics is really nice with the giant volume control.
I am using the lower powered KA 3500 in my office- price was right - free on CL !

My main system comprises a Mitsubishi LT-30 TT and an upgraded Sansui AU D11 with MAC Ultra Silver+ cables between them. Audiogon member "Ezekiel" aka Randy Young is who I've purchsed a few cupgraded vintage items from and have always been more than pleased.

Thanks for all the ideas. The Accuphase is probably more than I want to spend. I really liked the Sansui 20000 but the one for sale here comes up on numerous searches and the ad looks like it was pieced together from two other ads. I will stay away from that one. I never thought about Luxman and Tandberg. I will have to research those also.
Thanks so far on the suggestions.
I will be hooking this vintage amp up to Gallo 3.1 speakers.

Remember this too,at some point you will have to give the Unit some TLC.
So, pick one that at tech wont mind working on.
Some of the older European stuff -could- be problematic
with part, and some are a tech unfriendly.
I asked my friend at Northwest Audio repair,John who's the owner and repairman,"What do you think about Revox gear" and he went on about how hard they are to work on.

There are many great older units and I wasnt trying to name them all,but the ones that made a positive impression on me. I have heard GREAT thigs about the old Sonys as Johnnantais had stated, I want to pick one up too, I think there hard to find though.

I think older quality gear is just plain more musical, The old bipolar transistors just sound great. More body to the music,more flesh on the bones.

I also suggest the Sansui AU-717. My roomate had one and I still think it was one of the best sounding setups I ever enjoyed. Maybe a little sensitive to low impedence loads as once in a while it would go into thermal protection after extended enthusiastic sessions driving double Advents. Always cranked back up after a cool off period and sounded great again!