Soundboard Peculiarities on a Kirkman Vertical and two Brinsmead Grands

The following two images show the design of the soundboard on a Kirkman “Vertical Iron Grand” from about 1885. When played individually in isolation the lowest notes are acceptable but not exceptional; however when played with the octave or in combination with chords, they seem to expand and add depth and apparent bass fundamental to the sound so that one has the impression of a far larger piano and certainly not a vertical.

The bridge is suspended, or cantilevered, but the apron is quite narrow, far narrower than would be found on a German vertical with the soundboard glued to the back. Here the soundboard is floated to the left of the bass bridge, but most interesting is the design of the soundboard under the bridge. This is forced into an arch between two hardwood laminae and firmly glued and clamped at each end of the arch, so that the soundboard is certainly stiff but not rigid as it would be if glued to the back.

The next two pictures show parts of a very original soundboard design used by Brinsmead until about 1885. The soundboard is floated the whole length of the straight side and round the tail as far as the point where I have rested the bridge capping on the rim. From there on it continues more rigidly attached to the framing but detached from the iron frame and not clamped between this and the inner rim as would be more usual. I have not yet investigated exactly how things are arranged here. The piano was untunable when I acquired it, so it was impossible to judge all its tonal qualities, but the bass was exceptional. I think the high treble may be rather weak. This is a 5‘9” piano. Notice the perfectly straight termination of the long bridge, which is made possible by a bass section of 29 notes, exceptional for a piano of this era (1870). The bridges are far shallower than those on the later Brinsmead.

Finally a 5‘7” Brinsmead from about 1907, a piano that has wonderful character, power and sustain. The bass is big and round. This piano has only 25 notes on the bass bridge and I would have preferred 27 or 28. The bridges are good and tall. Notice the circular holes in the bass bridge. The soundboard is more ordinary in design but is still floated for about 18 inches, beginning at the end of the straight side and round to about the level of the fourth note on the bass bridge. From there on I believe it is glued and clamped in the usual way.