Speaker configuration Marantz 2270


I just received a Marantz MIJ 2270 from the late 70's. Looking for speaker opinions. I tested the unit on a pair of very cheap pair of bookshelf speakers. Granted the speakers were terrible, but I could tell the system could benefit from a sub; or a full range tower with bass speaker.

I am working within a budget of about 400-650ish. My experience with high end stereo equipment is limited, but am familiar with live speaker gear. I like the punch you can get from monitors, but have to keep in mind I would need a speaker that would like a lower powered signal being I'm working with 70 watts per channel, another reason to look at smaller
speakers.

In doing a search I noticed many people felt a sub of some sort is needed. I have found a few older passive subs with smaller drivers that had decent specs. I would like to entertain a passive sub as to get more the Marantz sound versus a powered sub. I would be concerned in blending
two set of speakers not knowing if I would need a crossover or not.

Being i am a newb I may be completely off base with my assumptions.
What suggestions could any of you provide me for my quest?

Thank you in advance
ricplaya
I have three candidates thus far

Boston accostic a200
Ads L570 (from a cool Member of this board)
Or Klipsch kg 2.5 with matching sub

All three models appear to be in good condition all in the same price range. Without the ability to hear these speakers before purchase I am relying on reviews and Exp from other posters how these would match up with the Marantz. I think they would all do fine, just looking for more info as to what way to go.

Thanks again!
I paired my Marantz 2270 with Klipsch KG4's and it seemed like a perfect match. The KG4's are easily powered by the 2270. The KG4's pump out some serious volume with no distortion when the volume knob is about half way up.
I decided on a pair of ADS L570's

At first I wasn't quite sure what all the fuss was about. After a while of listening these speakers I started to lime them a lot more. They are very uncoloured and flat.. Takes a little getting use to. Great for jazz, classical. Lacks a little warmth for rock and I think it needs subs to add some booty.
Just picked up some kg 4's

Have the ads L 570's stacked on top tweeter to horn. Does sound a little shrill on some very high notes, overall really enjoying this set up. Will crank it up more tomorrow to hear the difference at higher volumes.