Let me see if I can't straighten this out:
Loudness is actually pretty straightforward - It comes from having a high average level. It's really that simple -- when you turn up the volume control, you gain up the waveform, which means that the average level (which the ear is sensitive to) goes up.
Having a waveform which is dense in the middle, but not the edges (such as what you would get from running a multiband compressor at lots of drive, fast attack and fast release), it will sound like it's loud, except it really isn't -- it's just squashed.
If you then switch to a waveform which has been lighty multiband processed but fed into a simple clipper, it will sound much louder and more dynamic (edge density will be high at the peaks, and low at the valleys - yielding dynamics even though the peak level doesn't change). However, it will also sound distorted.
If you take that lightly multiband processed signal, and feed it into an advanced distortion cancelled clipper, it will sound as loud and dynamic as before, but the distortion is mostly gone. *This* is the secret to why Breakaway FM is so loud and open sounding. Loudness doesn't come from the front-end -- it comes from the back-end, period.
In plain english, both all three waveforms will be dense, but the difference is in *where* they are dense. If you want it loud, it must be dense at the *edges* -- not in the middle.
As such, the output of the back-end must be preserved and fed to the transmitter as precisely as possible. Adding any processing after the back-end (even if it's just EQ / Filtering) means turning the back-end into a front-end! And, as we know, loudness doesn't come from front-ends. If this is done, the final result will be neither loud, dynamic nor clean.
This is where the problem is. Tom, it is possible to use Breakaway FM for AM, but to do it you need a professional airchain -- an exciter / transmitter that will *accurately* reproduce Breakaway FM's carefully output signal. *Any* tiny bit of modification after Breakaway FM is a loss, not a gain. Any sweetening of the audio, be it EQ, Reverb etc, must be done *before* the back-end. Try connecting BaFM to an AM transmitter than has an AES input -- those that do will likely not have any problems with neither tilt nor high frequency response.
Anyway. Breakaway FM is an FM processor, as its name implies

. Tom, please create a new thread for our continued discussion on this topic -- let's bring this thread back on track, and talk about FM here only.
BofH, i think we're on the same wavelength, only using different terms. Having a lightly processed waveform and doing the peak-control by clipping, does indeed mean having some breathing space, since there will actually be transients, even if their peak level is virtually the same as the rest. If the distortion can be managed, this is indeed the key to being loud.
New 8500 firmware? More open but louder? Most interesting! I wonder if Bob finally improved that final clipper. I spent a lot of time in front of an earlier 8500 version, and found that you could get it very open and loud by turning off most of the distortion control (multiband clippers, hf limiters etc), and it sounded excellent on certain songs, but unfortunately terrible on others, since the final clipper itself does have distortion control.
I'd love to hear an example of what this new 8500 can do. Care to make an MPX recording, BofH?
On that note, BW Scott, you seemed pretty eager to get an editable page on mpxtool.com, and I took care of it promptly, but haven't heard from you since. What happened?
I also never got a response regarding the Analog Breakaway FM recording I made to appease your concern regarding the alleged unfairness of using an all digital path for Breakaway FM. Inquiring minds want to know

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Best regards,
///Leif
P.S. A new beta is in the works - should be here in a couple of days.