Having observed a phenomenon for an extended time, I would like to inquire as to whether others have the same experience. I have been called before to be too sensitive about unexpected mechanical responses of a harpsichord, but I’d like to be sure whether persistent phenomena are simply a natural part of every harpsichord’s mechanical response.
There are some notes on my harpsichord that will reverberate —with reduced intensity— after the damper has contacted the string upon releasing the key. Alternatively, these notes will also continue to sound if I touch the excited string with my finger to stop its vibration. Thus, this effect is not a matter of material choice for the dampers, but a consequence of structural resonance. On my Hubbard #625 kit, these notes are, within the limits of my (aged) hearing:
Back 8’
Octave
-
-
-
-
-
-
2
G#
A
3
D
D#
E
F
G (strong)
A
4
F
G
A#
5
F
G
G# & A#
Front 8’
Octave
-
-
-
-
-
-
2
F#
G#
3
D
E
G
A
4
D#
E
F
G#
A
5
Not all notes continue to resonate with equal strength: (a). the Back 8’ is voiced more strongly than the Front 8’ and (b) the loudness depends on how long the intended note builds up before the damper drops on the string —measured with a time resolution of tenths of a second (limit of the measuring tool); the bass has a distinctly longer time frame (~0.5 sec) than the descant (0.25 sec). This indicates that the soundboard vibrations build up with time, and (individual) short notes have a less pronounced “after-effect”, though fast playing of many notes could be additive, somewhat as if the dampers were (slightly) inadequately adjusted. — At least one note in the lower register elicits a single overtone response.
Is there a distinct pattern of this behavior in other harpsichords or does each instrument have its own pattern? I suppose no has really worried about this much for a number of period instruments, as no one has touched on this question during my Jackrail time?
Do you think this continuation of musical tone after the damper (or your finger) has stopped the direct string sound, is actually the resonance of some other string section which is undamped?
I suspect that is more probable than a structural resonance like the prominent boom tone of the enclosed case frequency, especially because of the number of notes with the phenomenon which you mention on your instrument.
Carey, let me see whether the 4-foot has undamped resonances. I had not though of that. I hardly use the 4 foot.
As always, my hat off to you. But that has to wait a bit until I get over my Back operation.
Wolfgang
Dear Carey. I had written this before I thought of my previous message, but had not sent it, yet.
I still send it in the interest of a more complete answer.
As always, I appreciate your comments. All I can do right now is to mention the red response below.
Do you think this continuation of musical tone after the damper (or your finger) has stopped the direct string sound, is actually the resonance of some other string section which is undamped? I do not think there are any undamped strings, because I am(was) done with going over all keys making sure I had no problem with any dampers.
I suspect that is more probable than a structural resonance like the prominent boom tone of the enclosed case frequency, especially because of the number of notes with the phenomenon which you mention on your instrument.
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