Hi! This is my first post on the forums. This post is huge, so I summarized it in the next sentence:

TL;DR:
Is there any difference between actions found on any of the Yamaha Motif and S-series (S08, S80, S90, S90ES, S90XS) keyboards? If so, on which model(s), and how does it differ from the other models?

Has anyone here had experience with either Yamaha’s Motif or S-series 88-key keyboards? I’ve added them to the list of considerations for a solid 88-key MIDI controller for my DAW. I know the Motifs are gigantic, but I recall the Motif XS8 (the light blue/grey unit) I played at Guitar Center having a nice action, suitable for both piano and synth sounds. This was back in 2008, so it’s difficult to tell how well the XS8’s action compares to anything else. All Motifs and S-series boards also have a proper pitchbend and modwheel, as well as at least 4 faders. The faders can be assigned to custom CCs on the Motif XS and XF models. So that means they should play nicely with my VSTis (Omnisphere, Keyscape, etc.)

I don’t like Yamaha’s Graded Hammer Standard (GHS) action found on other Yamaha keyboards. It feels cheap and dull to me. The newer Yamaha MX88 has GHS. I’ve excluded any keyboard using GHS from my list of candidates.

To help keep track of keyboard models and keybeds, I’ve listed them below. The main question is: which action does each keyboard really have? I can’t tell for sure, as you’ll see below.

Motif and S-series 88-key models are listed below. To their right, I’ve listed all potential action names I’ve encountered:
MO8: BHE* / BHA+
Motif 8 (Classic): BHE* / BHA+
Motif ES 8: BHE* / BHA+
Motif XS8: BHE* / WHA+
Motif XF8: BHE*

S08: BHE* (no monophonic/channel aftertouch)
S80: Initial touch* (no mention of BHE, etc. in manual)
S90: BHE*
S90ES: BHE*
S90XS: BHE*

* = action matches official Yamaha product manual and/or Yamaha representative claim
+ = action taken from unofficial source (cited below)

Keybed/action names (taken from the manuals and links below):
Balanced Hammer Effect (BHE) - name used in all official Motif manuals
Balanced Hammer Action (BHA) - taken from an unofficial source - is this different from BHE?
Weighted Hammer Action (WHA) - taken from an unofficial source - is this different from BHE?
Yamaha A88 K6 - taken from an unofficial source - synonymous with BHE?

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So, if BHE=BHA, which I believe it does, then all models listed above are BHE. But I have a suspicion that BHE *may* have been modified over the years, and that those modifications may exist across the XF8, S90ES and S90XS. There are two reasons I suspect this:
1.) There are differences in unofficial action listing
2.) A user claims a difference in feel between the XF8 and S90ES/XS actions. Their quote is below.

Quote:
“Having owned an S90XS (and ES), plus having put in a few hours of playing/demo’ing time on a Motif XF8, I can say that the user touch/velocity interaction is quite different between the two instruments - especially with regard to playing piano. While both have a balanced, hammer action (vs. a graded, hammer action - as found on Yamaha’s dedicated digital pianos), each plays a bit differently. I found the S Series to have a more ‘subtle’, piano like response. While I could play piano tones expressively on the XF8, the S90XS/ES provided a stronger sense of piano dynamic, IMO.”
http://forums.musicplayer.com/ubbthreads.php/topics/2242457/Which_Yamaha_Keyboard_should_I

I recognize that the above claim could be the result of velocity curve settings and not due to mechanical differences in the keybed.

==========================================================

Some additional references I used when researching Yamaha actions:

I did some digging on Google to figure out which keyboard has which action/keybed. I believe nearly all Motifs keyboards have the same action/keybed, which, according to this post, is a “Yamaha A88 K6”. This leads me to believe that A88 K6=BHE.
https://www.gearslutz.com/board/electronic-music-instruments-and-electronic-music-production/1149168-ultimate-keybed-thread-models-manufacturers-listed.html

Quote:
“All the Motif 8 boards have the same balanced, weighted action (Motif 8 Classic, ES8, XS8 along with S90 Classic and S90 ES). It is a sublime action.”
I read the manuals for these models. They all reflect this claim.
http://www.harmonycentral.com/forum/forum/Keyboards/acapella-18/327842-

Quote:
“The action on the Yamaha Motif ES8 is usually referred to as balanced hammer action, which is also used by the Motif XS8 and XF8, though there may be very minor revisions to teh keys in the newer models.”
Does this mean BHE=BHA?
https://www.gearslutz.com/board/showpost.php?p=11862345&postcount=28

If BHE=BHA, then what about WHA? Here, the MO8 is listed as having “balanced hammer-action (BHA)”. The XF8 is listed as having “weighted hammer-action (WHA)”:
http://www.vintagesynth.com/yamaha/motif.php
Does BHE=BHA=WHA? I sure hope so!

According to this Motif Wiki article, the action on all 88-key Motifs is referred to as “Balanced Hammer Effect (BHE)”, just like the Motif manuals state.
Quote:
“The balanced hammer effect action is the same action found on Yamaha’s S90 series keyboards.”
https://en.wikipedia.org/wiki/Yamaha_Motif

(continued...)

(continued...)

To add to my confusion…
Quote:
“If you liked the ‘action’ on the S90, you will love the action on the S90XS. Much better architecture and I believe based on a ‘real’ piano.”
http://www.motifator.com/index.php/forum/viewthread/460657/#539377

This suggests to me that the S90XS action varies from the S90. This is the second claim that the S90XS has a different action, but this time, in relation to the *S90*, as opposed to the XF8. But does it? And what about the S90XS action compared to the S90*ES* action? Do *those* vary as well?! I seriously doubt this, but I can’t rule it out completely.

More conflicting reports (XS8 vs S90ES actions...:
“Although both were similar, it did seem that the S90ES was better than the XS8, however, I wonder if I was being influenced by fact that the piano sound was better in the S90ES.”
http://www.motifator.com/index.php/forum/viewthread/444562/

Quote:
“The key feel of the S08, S90 and Mo8 and MoES8 are all the same balanced hammer action. The S80 has a different key feel. It’s balanced and hammer action but it is a different and in my opinion, lighter action. I prefer a heavy action.”
http://www.synthzone.com/forum/ubbthreads.php/topics/71295/S90_v_S80_v_S08_v_Motif

If my logic is correct, all this could mean that there are up to 5 (five) actions across all Motif and S models.
Action 1.) All non-XF8 Motifs (MO8, Classic 8, ES, XS) plus the S08 and S90
Action 2.) XF8
Action 3.) S80
Action 4.) S90ES
Action 5.) S90XS

To wrap up this post:
- All Motif manuals as well as the Wikipedia Motif article list all 88-key Motifs as using BHE.
- ...but the actions list in the above GS post show the XF8 as having BHE, while the other Motifs use “Yamaha A88 K6”. Why? Just a typo?
- The A88 K6 action appears to be BHE, based on how the GS actions list relates to the Motif manuals.
- It appears to me that the XF8 action is modified in some way, and not exactly BHE or A88 K6.
- The S80, S90ES & S90XS actions may vary from other models, based on user’s posts above.

Any thoughts on this? I know I went overboard with this post, but I haven’t seen anyone address Motif & S-series action differences beyond the references I posted above.

PS:
Here’s the official list of Yamaha’s *graded* actions, in case anyone’s interested. I can’t find any official documentation on Yamaha’s *balanced* actions outside of their product manuals. Does such a document exist?
http://faq.yamaha.com/us/en/article/musical-instruments/keyboards/digitalpianos/p_series/p-80/330/6575/