The stroke of a drum, which refers to the distance the drumhead is displaced when struck, can indeed affect both the amplitude and frequency of the sound produced.
Amplitude: The amplitude of a sound wave corresponds to the maximum displacement of air particles caused by the vibration of the drumhead. A larger stroke of the drum, where the drumhead is displaced more significantly, will result in a larger displacement of air particles, leading to a greater amplitude of the sound wave produced. This means the sound will be louder and more intense. Conversely, a smaller stroke will result in a smaller displacement and a lower amplitude, resulting in a softer sound.
Frequency: The frequency of a drum sound is related to the rate of vibration or the number of complete cycles the drumhead undergoes per unit of time. The stroke of the drum can indirectly affect the frequency by influencing the tension and tightness of the drumhead. When the drumhead is struck with a larger stroke, it can alter the tension and affect the pitch and frequency of the resulting sound. This is because changes in tension can modify the natural frequency at which the drumhead vibrates. So, a larger stroke can potentially change the tension and result in a slightly different frequency compared to a smaller stroke.
It's important to note that the stroke of the drum is just one of many factors that can influence the amplitude and frequency of the sound produced. Other factors include the drumstick used, the drumhead material, the size and shape of the drum, and the playing technique.