Interesting video.  Looking forward to everybody's thoughts on it.
My local dealer carries the Heritage series. I'll check them out.
I agree, very interesting information presented in the video.
Too bad they didn't actually allow us to hear the differences between the two models in the video.
What, no L-Pads? (Smiley Face)

The ’in the home’ images of the speakers adjacent to the music console, rear close to the wall, I cannot imagine a 15" passive radiator near a wall.

I would appreciate an optional method to tilt them back a bit. Within the base, a hinged horizontal front riser, tucked in = flat as shown, flipped down gives slight backward tilt. Aim the tweeters up toward seated ear level; avoid mid/woofer dispersion parallel to floor. Easy enough to do yourself, loose front block, temporary: remove or keep the rearward tilt.
I'd love to hear them. 
I'm wondering why Klipsch didn't replace that 15" passive with ports? The video claims the passive gives "lower Bass" but I think that is wrong. It might make MORE bass (amplitude), not lower (frequency).
The new Heresy IV has a rear port.
Can't wait for price...
OP a passive is a much better option than a port. You’re stuck with a given port size unless you go smaller. But the moving mass of a passive can be varied to blend perfectly between Room, Amp, and Mid drivers. I use putty down to the size of a pepper corn.

No matter the driver it still can only go so low without issues, the same problem exist if the PR were to be OVER dampened. It would BOOM the room..Thus the need for the PR to roll off BEFORE the driver. The real trick it to get the two to work together, with the putty trick..

That dipole setup, no matter what JBL calls it, is pretty effective. The "closer to the wall thing" is giving a quicker FIRST reflective surface little room to BOOM.. The roll off is quicker and more controlled. NO PORT NOISE!! Better bass delivery system.. plane and simple..

I like JBL Bass!! I always have.. Heck i like JBL.. 
Everest, series. I'll take a double portion, thank you very much..:-)

Regards
I think I read that the price is ~4500.00.

Oz



I’ve done a lot of research into high efficiency speakers I would consider buying over the years. Here is the skinny:

Price shows as ~$4500. $500 more than III. Reviewer says in essence a clear difference in sound with good recordings due to midrange driver and crossover.

Would have to hear a/b to know for sure. Of course the differences as stated in the article would seem to make the additional cost a worthwhile investment. Probably worth more than $500 as described.

I’ve liked Forte III when I’ve auditioned off good modern SS amplification. Too big still for my use practically at present time though.

If I had a tube amp and need for the high efficiency...I would probably lean towards these as a cost effective and nice looking option. This is Klipsch Heritage line which has historically always been all about tube amps. Forte came later in 80’s but only available for a few years originally so apparently not a big hit back then. Tube gear has found a niche since then. Volti Razz is similar and $4999 so that is another strong option.

Tekton is also a cost effective option to consider in this league for tube amps, but not nearly as efficient as these Klipsch Heritage series horn based designs though and then there is the aesthetics...totally different.

Neither Klipsch or Tekton truly an "easy load" in general from what I read so performance and sound may still vary from amp to amp. I’d lean towards Fritz Speakers for that (an easy load). Those are less efficient but a very easy load and I have heard sound wonderful and plenty loud in a modest size room off a flea power set amp...a most impressive feat.
Can't wait for mine to arrive.....was about to pull the trigger on IIIs, but they were out of production so I put deposit on IVs....
I bought the Forte IIIs a month ago, and they are amazing speakers in my multi-use room (35 ft x 18 ft). I have them powered by Classé CP-800 and CA-2100 combo ... magical and very musical. My music collection has never sounded so good, period! Last night I saw the Audio Advice YouTube video on the Forte IVs and decided to contact my dealer to see if they would do an exchange given how recently I got the IIIs. They agreed and now I have a pair of the IVs on order. Music already sounds very real and live with the IIIs and I’m expecting the IVs to be even better. I’m really looking forward to it.
Send a Valentine to your Dealer!
No kidding.  Good dealer and almost perfect timing (you got the use of the III for a month plus your wait time for the IV's).
As a current owner of Forte IIIs, I'd be curious about crossover improvements in the IVs. 

I've considered the Forte III upgrade kit from GR Research, it includes upgraded crossover, bracing and damping. 

The crossovers requiring soldering, however, which is not a skill i possess. 


Live show with Klipsch about the Forte IV. 
https://youtu.be/gnt6JZa_HDM
They did a great job of keeping it quiet while they were working hard on the Forte IV...   mine arrived today,picking them up in the morning.
Oddiofly,

I am interested to hear your thoughts. They say the paper bass driver takes a longtime to loosen up and break in, as in 400 hours. 
I am interested in the Cornwall IV but still want to hear about the new klipsch in general as I still have my doubts I will like them. 
Klipsch did a great job on this speaker.   Haven't spent a lot of time with them,  but they sound awesome . 
I'm hoping we hear more from Forte IV owners, these could be a great option for me with my low-watt amp.
I received mine last Friday. Like oddiofyl says, they do sound great. Midrange feels better than Forte IIIs. With the IIIs I felt really came to life after some 300 hours of playing. I don’t have that much play time on the IVs yet. It feels like they may be less efficient than the IIIs but I have no way of proving that. The black ash with salt and pepper grills looks great.
Congrats to all the new Forte IV owners. I have been enjoying Cornwall IVs for seven months now and am extremely happy. I imagine the new Forte is excellent as well.

Oz
Thanks Ozzy.... I really am curious what the reviews say.  I heard the C IV and H IV and bought the Forte IV sight unseen after hearing it was voiced like its big Brother.