I know there were 36 mm models in the past, with solid and sapphire caseback. But they had the gong attached to the back of the movement, while the new caliber 956 has the gong surrounding the movement, thus effectively increase the overall diameter.
If i am doing my math :
The old 36 mm case contain a 29 mm caliber 914. So there is a 3.5 mm space between case and movement (36 - 29=7, divided by 2=3.5 mm). I suppose the space is needed to amplify the sound.
If on the new caliber we assume the thickness of the gong is 2 mm. Then the overall diameter (movement + gong + space)=29 + (3.5 + 2) x 2=40 mm.
So, in my theory, there is very little possibility JLC can make memovox below 40 mm case, unless they design a new midsize caliber, or move the gong back to the back of the movement, which i doubt they will do.
Curious to hear your thought. Because i am contemplating to buy the neo vintage 36 mm memovox...but the difficulty to obtain from overseas and high custom tax, make me think to wait for new memovox in smaller size.