Have never chanced to work with these former studio staples. But I see that they have a hallowed status in some hi-fi circles.
I did hear the equator audio research q15s which have a similar design approach. I'm not sure they were calibrated correctly (the low end was not consistent) , but they did have superb imaging and the most robust phantom center I have ever heard. It was quite disconcerting to see that there was no speaker in the middle.
Now, a company called Great Plains Audio is selling raw drivers based on the 604e. I was considering building a pair... its not insanely expensive, and can be powered with less than 100 watts.
I'd like to know what the veterans think. Can the 604e hold its own amongst today's high tech offerings?
assuming you are going to build the right cab and your room is on the biggish size .. you will have a lot of fun with them.. not sure i would mix on them but playback and checking mixes ..big fun sound.. I think that the super high efficiency speakers are better for listening into a mix to hear the little micro details
btw.. the great plains guys seemed like wonderful folks the few dealings I have had with them.