I've been listening to my JTR Noesis 215RT speakers quite a bit in the past week. I have a few more adjustments to do with my acoustic treatments and even ordered some more treatments today.
Here are measurements of the left and right speaker from 3 ft away. The straight pink line is the loopback measurement for reference. The slight dip at 400-500 Hz is from a reflection. You can see that these are extremely flat speakers. If your head is lower than the center of the horn, then the higher frequencies have a slight rolloff that is very pleasant.
The 60 degree horn on these is very similar in size to the horn of the Danley SM60F. The large size allows for a low crossover point of 350 Hz and the 60 degree angle allows for the depth necessary for low frequency pattern control. By having the same vertical and horizontal dispersion, the listeners in all rows of a home theater get equal sound. With a horn that changes vertical vs horizontal, the vertical dispersion becomes narrower at higher frequencies. On a JTR speakers, 1 kHz and 4 kHz will be similar. On a 90 x 45 horn, the directivity will change. This is beneficial for long throw commercial theaters or outdoors, but not in a home theater.
These are truly a single point source speaker with the sound originating from the center of the horn completely time aligned and in phase.
I mounted a barn door track on both sides of the room so I could slide treatments back and forth and change out acoustic treatments. Because of the directivity of horn and pattern control I found that the sound became harsh if there was too much low frequency absorption at the sides. This was caused by two things. First, I initially used an acoustic panel designed to have more low frequency absorption. Switching to a broadband absorption panel fixed the issue. Second, absorption needs to be placed at the sides where the frequency response at the side becomes fullrange. If the absorption is too close to the front wall, only low frequency energy is hitting it and being absorbed. This again ruined the sound at the listening position.
I now have the room almost how I want it with the exception of 3 panels. I wish my room had a lower noise floor, but there isn't much I can do about it at this point. With regard to the speakers and system as a whole, I really don't think I've heard anything that sound this good. The low frequency extension, high frequency extension, focus, clarity, soundstage, smooth frequency response, and dynamics that all add up to an incredible listening experience.
To change the topic slightly, my Lab Gruppen rep stopped by last week so I invited him to my house. We spent a couple hours comparing some LG amps to my Cherry Maraschino amps by checking maximum output and clipping behavior. We used the E 8:2 and the D Series 40:4L. Both amps ran completely silent and both had no hiss out of the 215Rt. Both of these amps have Rational Power Management. This allows one channel to use lots of power while another channel uses a small amount. On the 4 channel amps, two channels can use half the power for mains while the 3rd channel can use the half of the power for a subwoofer. Or, if you use a 4 channel amp for LCR the maximum power is actually split up among the three speakers. You aren't really wasting an amp channel that is sitting idle.
The E 8:2, even when used with a single channel, had 6 dB less output than my Maraschino. The 40:4L on the other hand matched it very closely. It doesn't distribute all its power to a single channel so had much more output available on other channels, too. I'm thinking about offering the E series going forward. With an 80 Hz XO and the high efficiency JTR speakers, they will make a great choice for external power. They are auto on/off, can be used in a living room since they are silent, and an amp can be used for a main and surround with the majority of the power going to the main when necessary. A pair of the the E 10:4 series will provide some nice headroom for a 7 channel system.