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Anybody know when piano makers started to notch the bass bridge so that the bichords are notched at 90-degree angles to the strings?

I did a search for Steinways from 1915 and they are not notched in this way. Also my old trusty 1915 grand is not notched this way. But my newer Baldwin is.

The other thread on the new Mason and Hamlin has a close-up picture of the bass bridge which made me curious.

Has anybody noticed a difference in tone? I suppose there might be, since on the strings are actually of different lengths on the bichords, when it's not notched in a zig-zag fashion.

In order to have the same length in the strings of an unison, the bridge pins have to be in a line parallel to the capo d'astro/agraphes/pressure bar/V bar, whatever bearing points on the tuning pin side of the string the piano happens to have, and not to be at 90° to the strings.


And in most, if not all, of the pianos I have seen so far this is not done.

I don't know why. At first sight it seems not difficult to do.

I agree, and that's part of the reason I'm curious about this. I'm wondering if it's something nobody in the industry really 'noticed' until a certain era.

Both the grands I'm looking at use agraffes, and the termination is at 90 degrees on the tuning pin end.

In that case the strings are the same size.

In other cases, I suppose the difference in length between strings is so small that it makes no difference when tuning the unison.

No, actually they're not, because the bridge is at an angle to the agraffes. It's clear when you look at the bridge that the terminations are not at 90 degrees to the strings.

I've always been intrigued also why the strings of a unison are not the same length, if they are meant to be tuned at the same frequence.

Maybe a piano designer like Del Fandrich can enlighten us.

I think the admonition "Time is money" comes into play here. Many makers do notch. Many don't. Some notch only on larger models or pianos that include tri-chord wound, and then only the bi's and tri's. (Like S&S model "D") I can't recall whether or not S&S notches the bi's on the "B" or not.

All bass bridges are fully notched when they come out of our shop, regardless of any original design with a lack of notches. I prefer matching string lengths and yes, I do believe I can hear the difference, at least on smaller pianos. The partials line up better, though never perfect on any wound unisons.

No, I can’t. It has always been a puzzle to me why some manufacturers—including some that have been regarded as “high-end”—have not bothered to notch the bass bridges. Seems like something of a no-brainer to me. Like Dale, any piano coming out of my shop that has received new bridges or bridge caps will be notched so the two strings will be the same length.

ddf

I have pictures of Steinway #1199, Currently at the Smithsonian in DC, personal photo's from Steinway #1226 and Steinway # 1548, all straight strung and with notched bichord sections. I also have personal images of Bluthner #678, also straight strung and with notched bichord sections.

The idea has been around a long time.

Motive for the decisions to do or not to? I would really enjoy a conversation with Theodore and Henry Steinway as to their motive on a great many things.

Of course, having the strings be the same length depends on the orientation of the agraffes as well as the shape of the bridge. You can argue about the striking points being the same, but that depends on the orientation of the hammer.

That is interesting, but I would think it especially interesting to see when notching on bass bridges on overstrung pianos began (or if it was there from the beginning). Somehow I imagine it's more natural on a straight strung piano to just keep notching all the way down in the same manner as the treble. Just because it's all one bridge and so there's obvious place to stop (maybe the beginning of the wrapped strings, on second thought . . .).

I have photo's of early overstrung pianos with notching in the bichords.

It is unlikely the decision to notch or not is in any way related to straight vs overstrung.

That is why I said, "so the two strings will be the same length.”

The very slight difference in hammer strike point will be inaudible.

ddf.

My point was that as long as the line through the center line of the strings forms the same angle with the bridge pins as it does with the agraffe, the lengths of the strings will be the same. Whether the bridge is notched or not, whether that angle is 90° or not, makes no difference, although there may be physical limitations.