What is the Altec 604 sound?

I have limited exposure to Klipsch speakers, but from what I have read on forums, Klipsch Cornwall can be fatiguing.  I did have a brief listen to Forte IV's and I thought they were ok, but prefer my Altec's,   I typically listed at 65 db average and they sound very much alive and dynamic.

I have Altec 604E from 2005.

I never listened to Altec GPA. I don’t know how do they sound. It can be different from old 604s.

My 604 is very easy to drive and sound is very dynamic without feeling of any compression. The bass is fast and has texture but not deep. In my 9 cubic feet cabinet it doesn’t go deeper than 40hz. High frequencies go up to 10khz, so I use supertweeters.But new GPA should be more extended on high frequencies.

These speakers wonderful for jazz and vocals. They can play rock and classical music too.

They can play in midsize rooms. Even 200 square feet is ok. Because the are coaxial they can play from 8 feet distance.

Here are my Altec 604E videos:

https://youtu.be/Nlo9qR4-I0c

https://youtu.be/ooFTaeJsdQ8

Model E was in production from 1964 to 1973.

What is special about the Altec 604 - The 15 inch driver plays a very wide frequency range up to 1500Hz. The mid bass driver moving mass is very light (compared to JBL and modern Tannoy) to afford to play midrange. Driver quality is on a higher level similar to JBL and better than EV drivers used in Klipsch. Lightweight 15 inch Altec 604 and 515 drivers have better low midrange and upper bass texture compared to JBL drivers, even legendary JBL LE15. JBL drivers have deeper and puncher bass.

The main drawback of 604 is that the 15 inch driver can’t play equally good bass and midrange. The old series: 604, 604b, 604C have a better midrange texture on trade off of bass depth and weight. More modern series have a better puncher bass on price of midrange texture. Old 604 have sectoral--stile horns. More modern models from H, have improved Mantaray horn and phase plug that makes upper mid and high frequencies sound smoother and extended.

https://www.technicalaudio.com/pdf/Duplex_Speakers_related_to_Altec_604/DUPLEX.html