what speakers for 4k or less new or used

Go for the Merlin VSM-M, tube harness, battery BAM. Can't go wrong with these.

I have owned many speakers including Merlin VSM's, Silverline Sonata's, Gallo Nuc Ref 3's, Talon Khorus xII's and many others. Some of these cost up to $10,000 - $18,000 new. However, the speaker I have enjoyed the most is the Usher 6381. Very, very formidable speaker. Build and sound quality are the best value I have heard in high end speakers. Cost is $3000 with a slight dealer discount new.
Does everything so right. Speakers are full range and always in control of the music. So intimate souding! Anyway, that is my 2 cents worth. I felt they outperformed the Merlin in every way and I love the Merlin VSM so much I owned it twice.

Check out the offerings from Green Mountain Audio. The sound of the Callisto is stunning.

The Tyler Acoustics Linbrook Signature System 2 piece (the one with the bass modules) can be had used in your price range for 3-4K (5K new).

I own a pair of these, and I can honestly say that I have not heard anything I have liked *as much* until you get to the Von Schweikert DB99 mk IIs, (and they are just shy of 10K a pair new). There are better speakers I have heard above 10K, but value-wise, the Tylers are tough to beat. Definitely worth seeking out a home audition, IMO.

One other possibility in your price range used would be the Dali Helicon800s (4K used, 6K new). I rate the Tylers as better, but these did stand out from the rest of the pack at their price point, and they are sold in stores (so they are more readily available for audition). Also worth a look, IMO.

---Dave

Shahinian Obelisks. If you have nothing against a polyradial design they are the cat's meow in this price range. Midrange to soothe the soul, and very fine bass and high end extension to boot.