Soundboard crown/no crown

Tuner

This post is not about repair or replacing an old, worn or defective soundboard. It's about new pianos that supposedly don't have any crown by design. I've asked a few people this question but never received a good answer.

I was surprised to learn there are certain manufacturers out there that not only advertise their model doesn't have any crown but seem proud of it. C. Bechstein is one of them on their Academy line (model number starts with an A). Their highest line (Concert series) advertises a crown and they seem even more proud of that line.

So what's the deal here? There's got to be at least SOME crown on it or wouldn't the strings pressing down on the bridge bow it down?

While we're on the subject of crown, if there is a crown expert here, are you familiar with how Kawai crowns their boards? The thing I heard about those is that they're crowned in one plane only, not omnidirectional. In other words, picture a paper towel roll cut in half the long way vs a bowl. I was told that by someone trying to talk me into another brand so there is a touch of bias possible but I don't believe they're intentionally trying to deceive.

Bellyman

There are definitely different techniques and ideas out there when it comes to soundboard design. I've never heard of "zero crown" being a thing but can't say I'm 100% surprised by it. To me, that would suggest that it is designed such that the crown of a soundboard would be exactly flattened by the downward pressure of the strings. It would still have "tension", just not "crown". At least that's the way my mind would picture it, I could be wrong. Exactly what that accomplishes, I don't know. It would be interesting to hear other techs chime in.

I'm kind of old and a has-been more than up on what individual manufacturers are doing. I'd say "the proof is in the pudding", or perhaps better said here, the proof is in the sound. Do you like it? Do others like it? If so, there must be something good happening, even if it's a different design than customary or typical.

I'll be interested to read others' responses. 🙂

keff

In a zero crown design what would be the required humidity level to balance upward and downward forces? If humidity exceeds the specification a crown is restored and if less than spec it would potentially crack. The idea of a wooden soundboard without a crown is a turn off for me.