I measure 161mm on my Montage 7 which is 1.8% shorter than the lower range of widths described within the below (originally wikipedia) reference. The key width (of one key) is the same as a Steinway D measuring at 22mm.

I'm guessing Yamaha figured you wouldn't notice less than 2% of a difference.

According to other sources, "more" modern French/German pianos had octave spans of 159mm - so considering 159-165mm as the range - 161mm just about splits the difference.

As a reference: http://music.stackexchange.com/questions/20290/is-there-a-standard-width-for-piano-keys

This question got me curious, so I started googling. Keyboard size is not officially standardized (there is no committee creating and enforcing standards), but in practice, there is very little variation.

Browsing through forum topics on www.pianoworld.com, people measured 88 key keyboards from anywhere between 48 inches to 48 1/2". Wikipedia ( http://en.wikipedia.org/wiki/Musical_keyboard) describes the width of an octave on a modern keyboard as 164-165 mm, which leaves almost a centimeter variation in width over the entire keyboard.

There is also the option of buying a deliberately manufactured smaller keyboard, as described at http://www.smallpianokeyboards.org/keyboard-history.html. This would have a width as small as 141 mm for an octave, or over 2 cm smaller than a standard. I don't play piano, but as a small handed woman, that sounds pretty attractive.

Historically, from both the wikipedia and the smallpianokeyboards.org sites, older keyed instruments had octave widths as small as 125 mm, but not modern pianos.

For piano-like instruments, such as midi-controllers and cheap electronic keyboards, smaller keys are common when manufacturers have goals other than producing a standard piano.

... Encyclopedia Britanica

"Although some early organs had very wide keys that could be played only with the fists, stringed keyboard instruments seem always to have had natural keys no more than an inch wide, yielding an octave span of 7 inches (17.8 centimetres). The octave span on the modern piano is about 6 1/2 inches (16.5 centimetres), much the same as on Flemish and Italian harpsichords of the 16th–18th centuries, whereas that of English keyboards was generally 6 3/8 inches (16.2 centimetres). On most French and German instruments of the 18th century, the octave span was even narrower (6 1/4 inches [15.9 centimetres]), permitting the playing of tenths—such as C to the second E above—by a hand of average size."

Thanks

I think other synth manufacturers have wider keys on their non-weighted keyboards so its a bit of a mystery with Yamaha.

I found the following on the Yamaha web site:
http://faq.yamaha.com/us/en/article/musical-instruments/keyboards/digitalpianos/cvp_series/198/8717

... going by that data, the Montage 6/7 is 3% shorter scale than the Montage 8. Still small potatoes and 159 seems within range of modern pianos. Not that a synth is a modern piano at all. The fully weighted 88 key version is trying to be more of a piano ergonomically so it makes sense that it would be the same as a Steinway.

I'm showing my age, but when the DX7 came out, I got an early one in the end of '83, having played a breadboarded pre-version in Hamamatsu in the Spring of '83 when I was there on tour......

I played that DX7 nearly all my waking hours for months. I got a stiff neck from looking down at the LCD screen while programming for many of those hours.

BUT here is my POINT, and why I chimed in:

Eventually, I found my octaves on real pianos in studios were missing a lot, I was getting the low note with my thumb, but I was often hitting the higher octave key along with the note directly before it with my little finger - - - and I ascribe that unfortunate series of events to the shorter octave lengths that Yamaha seems to prefer. ALWAYS HAVE. I had actually 'learned' that interval from DX7 overuse.

Every few years, I measure 4 or 5 octaves on various keyboards in a place I have occasional access to: a V-Synth, the Hammond B3, the Mason Hamlin (real) baby grand, the Sequential T8, the Motif Classic, a Yamaha CP300, Roland XP-50, a few Ensoniq synths, a Wurlitzer EP... The MX49; a Novation ReMOTE SL Mk1....and Yes - many of the Yamaha keyboards do come out on the short side.

I wish they didn't, but they have so many virtues, that I still get em and use em!!!!

But it is significant. I'd heard it said, more than once, (without intending any racial slur) that Yamaha was tailoring the keyboards to the typically smaller Japanese hands; I have NO idea whether this is the least bit true, but it does go to show that Yamaha's narrower keys DID get noticed and discussed, even back in the day.

Here are rough measurements in mm. of 61 keys (5 octaves plus the next C) on various keyboards:

Mason Hamlin Piano 85.4
Roland XV 85.0
Korg Karma 85.0
Ensoniq SD-1 85.0
Alesis QS61 85.0
Yamaha CP300 84.9
Yamaha Montage8 84.9
Hammond B3 Organ 84.9
Yamaha s70xs 84.9
Hammond-Suzuki SK1 84.9
Novation RemoteSL Mk1 84.9
Roland V-Synth 84.8
Prophet T8 84.65
Wurlitzer 214 EP 84.4
Roland VR-09 84.0
Roland JD800 83.7
Roland XP-50 83.6
Motif Classic 82.7
Yamaha CS-2x 82.5

(underlined = 'weighted action keybed')
I'm sorry, I don't have immediate access to a Montage 7 or 6.

Some more measurement fun/discussion:

http://www.motifator.com/index.php/archive/viewthread/308057/P15/

I'm guessing your chart of measurements is in cm, not mm?

Because 84.9 cm = 849mm - 5 octaves = 849/5 = 169.8mm is more in the ballpark (still need to remove that extra key).

Removing extra key:

5 octaves = 60 white and black keys. Each octave has 7 white keys per octave.

849mm / [ (5 * 7) +1 ] = 849mm / 36 = 23.583 and-some-change mm That's 23.583mm width of one key. (the +1 is for that extra key)

849 - 23.583 = 825.4167 mm for just 60 keys instead of 61. Now div by 5 (5 octaves) = 165.083 mm per octave.

Not exactly Yamaha's published 164mm per octave, but close enough. That's +0.7% "error" (vs nominal 164mm per octave). Pretty darn close.

Thanks Jason! Will check out that link. And oops, cm, not mm, right.:)
The 0.7% error is no doubt, also attributable to me - I wasn't sure whether to measure the space at the end of the 61st note (and that key itself shouldn't have even been included, true...)

The airgap should have been measured but that would only account for (airgap distance)/61 amount of error - which doesn't amount to much at all. The more white keys you measure, the higher the accuracy because things like missing one airgap will have diminishing contribution to the measurement error - and 61 was already enough for that, I believe.

To reiterate my answer to the original question: "because there is no standard", and "it's not off (from say a Steinway) my much" (except yes, noticeable by some), and - in historical context - the chosen scale for the 6/7 matches physical acoustic pianos designed for allowing for extended reach of notes as the German/French pianos - which seems ok for a synth.

Maybe Yamaha can chime in on some semblance of an official answer.

Is the key width / octave width of a montage 6/7 the same as a motif XF/XS 6/7?

Lots of comparisons in the thread with acoustic pianos and synths from other manufacturers. Curious of the spacing compared to the Motif line and other Yamaha synths.

Montage keybed and the XF/XS[6,7] should be identical. Reference https://www.yamahasynth.com/forum/montage-6-keybed

The rationale for discussion of key width and spacing vs. a traditional piano is because the notion is that the synth action keybeds on Yamaha products are too miniature - and I would suppose a piano-like instrument would be compared to a piano when setting expectations.

https://yamahasynth.com/forum/fsx,-is-it-just-me

Motif ES6/7 = FS Action (lead weights)
Motif XS6/7 = FSX Semi Weighted Action (lead-free weights)
Motif XF6/7 = FSX " " Action
Montage6/7 = FSX " " Action

So Montage "synth action" keybeds are the same as XS and XF "synth action" keybeds.

I would imagine from a spacing/span/width perspective - Montage's synth action goes back identical further than the XS.

Hi all, if you need some help you can check out my articles. I wrote different topics regarding music. I even wrote some instrumental reviews you guys can check them out. Here is an example, this is for those who want to understand the piano keyboards layout. https://musicadvisor.com/piano-keyboard-layout/

Hope you guys enjoy and let me know what you think.:)