Where does the sound come from for slap /pop?

[Uriah Sheep]

Hi all,

Wasn't sure where to post this, so I thought miscellaneous was safe. Feel free to tell if a better location is present. When you slap and pop on a properly set up bass is the string you are slapping making contact with only the highest fret (fret closest to bridge)? Or is the slap sound coming from the string hitting multiple frets? Thanks for reading.

 

[Lagado]

My top fret bears the indentations. If the neck has relief, the top fret should be the highest fret, following the curvature of the neck.

 

[garp]

As noted by @Lagado, definitely the top/highest fret on a properly-setup bass is the primary source of the unique tonal character of slap. However, slap also creates different string vibrations than finger-style or pick-style playing. I seem to recall watching some high-speed cinematography/videography a few years ago of various bass techniques, and slap created a quasi-unique sine pattern that also contributed to the tone.

 

[Uriah Sheep]

Thanks for the input folks. I was practicing a bit on my mim fretless jazz bass and tried slapping just to fool around. It got me thinking about point of contact to create vibration. Thanks again for the replies!