How can I pluck strings (with changing length) with constant energy?

[mt1815]

Homework Statement

I am doing an Extended Essay on Physics

Relevant Equations

n/a

Hi I am doing a physics investigation on the research question "If the string length changes (same tension) does the spread and amplitude of harmonics change?".

If I'm not mistaken, plucking energy should be a control variable. So, I want the energy of my plucks to remain consistent (through trials of changing length). Is there an easy way to accomplish this (at home) and measure the energy input (for further calculations)?

(edit)
I had an idea to attach a pendulum to attack the string with constant energy. But then I would not be able to measure the energy applied.

 

[hutchphd]

You might investigate the mechanisms of the harpsichord and pianoforte. They didn't call it a "softloud" for no reason.