For the meat-and-potatoes sampled sounds, the CP88/73 are going to have the same sounds as Montage plus a few that Montage doesn't have (like the uprights - I don't think Montage have exactly these same samples). The lack of sliders may or may not be a care for the organ control. If organ presets work - this should be OK.

I really like the CP88/73 concept - but, if I ignore the CP88's triple sensor and a few samples (which can be expanded on Montage if ever offered), the tonal palette of the two lines of keyboards have lots of redundancy. Adding a keyboard - typically consider complementary features so if was to add - and wanted a weighted keyboard - I'd probably gravitate towards something with completely different sounds to gain both a new keyboard and new choices in the pianos/organs/etc.

I should add I like the idea of 73 keys. My only hesitation is the action. I believe it is balanced? What is that comparable to? If it’s like a p-125 that’s great but if it’s closer to synth action that’s not what I want.

For the meat-and-potatoes sampled sounds, the CP88/73 are going to have the same sounds as Montage plus a few that Montage doesn't have (like the uprights - I don't think Montage have exactly these same samples). The lack of sliders may or may not be a care for the organ control. If organ presets work - this should be OK.

I really like the CP88/73 concept - but, if I ignore the CP88's triple sensor and a few samples (which can be expanded on Montage if ever offered), the tonal palette of the two lines of keyboards have lots of redundancy. Adding a keyboard - typically consider complementary features so if was to add - and wanted a weighted keyboard - I'd probably gravitate towards something with completely different sounds to gain both a new keyboard and new choices in the pianos/organs/etc.

That makes sense. What I currently am using is the Korg Grandstage, which is great, but I just prefer the action and overall sounds of the Montage. My thought is that perhaps a CP88 can replace two keyboards (Grandstage and Montage). I also have a Nord Electro, which I would keep for now for the sounds, sliders and action. Who knows? The CP series might fit the bill on all of those if I go that route.

I'd have to look at the CP's documentation to be sure - but I think the CP isn't going to have as much sounds to choose from. I think for the meat-and-potatoes as originally described here - it's hitting all of those plus a dash of other sounds. Montage has the benefit of deeper editing capabilities - but I didn't gather that was a goal.

The CP73 has the same keybed as the Montage 8 with aftertouch stripped out. That's the basic summary of what you get as far as I understand. As such, it's not graded. In other words, balanced meaning all keys are the same weight from lowest to highest key. If Montage 8's keybed appeals - the 73 will be the "same" with exception of aftertouch. Even down to the double vs. triple sensor of the CP88 - which is graded and has wood-center white keys.

I should add I like the idea of 73 keys. My only hesitation is the action. I believe it is balanced? What is that comparable to? If it’s like a p-125 that’s great but if it’s closer to synth action that’s not what I want.

I'm pretty sure the balanced hammer action on the CP73 is still weighed, just not graded. So the feel of the keys are the same from low to high notes. Since they're just announced I haven't played on the CP73 yet. I don't know how heavy the action is. Since it is geared toward a keyboardist with a synth emphasis that is also a good piano action, I expect they are a little lighter, more like the right side of the piano, but that is a pure guess. Obviously the folks demoing for Yamaha exclaim the great feel of the 73, but I'd wait until you can check it yourself. The simplicity of the interface would be the main attraction for me.

I have a P-515 and it is really a great action with two really good piano voices (maybe even great). You really should try the pianos for yourself and see if they feel right to you. I'm looking for a very real piano feel. The CP88 should be very close if not identical to the P515 in feel (except that it might not have that Escapement notch - NW-GH3 vs NWX). But definitely try each before you buy.

I should add I like the idea of 73 keys. My only hesitation is the action. I believe it is balanced? What is that comparable to? If it’s like a p-125 that’s great but if it’s closer to synth action that’s not what I want.

It is a hammer action, so closer to the p-125 than to a synth action, but balanced (same feel across all keys) as opposed to graded (heavier feeling low key, lighter feeling high keys).

I'd have to look at the CP's documentation to be sure - but I think the CP isn't going to have as much sounds to choose from.

61 sounds, with the next ones due in September. So far, we have these:

Grand Pianos (5)
Upright Pianos (2)
CP80 Pianos (2)
Layered Pianos (2)
Rhodes (5)
Wurli (3)
Clav (2)
Harpsi
DX/FM Pianos (6)
Pads (4) (incl. "air choir" )
Strings (4) (incl OB synth strings)
Drawbar organs (5)
Transistor organs (3)
Pipe organs (2)
Glock
Vibes
Xylophone
Marimba
Other bells/chromatic percussion (3)
Lead synths (2)
Bass (3) (acoustic, electric, synth)
Guitar (2) (steel, clean)
Synth brass

No accordion, harmonica, flute, violin, trumpet, sax, non-synthy brass or voices for example... It may be all some people need, but even in terms of "basic" sounds, it doesn't really come close to a Montage (or Grandstage)

The CP73 has the same keybed as the Montage 8 with aftertouch stripped out...If Montage 8's keybed appeals - the 73 will be the "same" with exception of aftertouch.

I don't think we know that for a fact, I think that was only one rep's subjective experience of what he thought it felt like. Yamaha has already employed a version of BHE without aftertouch (in the MO8), bu unlike that, this one is called BHS, not BHE, so I suspect there is more difference than simply being a Montage 8 BHS without aftertouch. The low weight of the board also implies more of a difference.

And getting back to the initial question, if I was going to look for a hammer action controller to connect to a Montage, I'd look for something that had the ability to transmit on multiple MIDI channels simultaneously (zones), Otherwise, unless you get additional hardware involved, you're limiting yourself to either just playing 1 of the Montage 16 Parts on the external keyboard at any given time, or only 1 of the Montage 16 Parts on the internal keyboard at any given time, both of which are restrictions you might as well avoid if possible,

Moderately priced hammer action boards with at least four zone control and also a selection of internal sounds would include: Kawai MP-7SE, Kurzweil SP6, Casio PX-5S, I think Roland FA-08 and RD2000, I think Korg Kross and Krome 88s.