Who makes a 4-way speaker besides Revel?

Linn make some speakers that are 4-way and can be bi-amped. This is one:

http://www.linn.co.uk/majik_140

You don't say if y ou are looking for new or used...but if used, then the NHT 2.9 and 3.3 are both 4 ways and bi-ampable.

unless the ar9's are somehow going bad, they will compete with many speakers out there at 10 to 15k and beyond....still a benchmark design, and they wrote the book on 'balanced' sound....think a long time before replacing.