Not sure if anyone is interested in this sort of thing…

For one of my courses this spring, I did some study of spectral composition. Part of that involved creating a Stick piece using spectral processing. I used the spectral content of various articulations and morphed between them.

Here's a pic of the first two seconds of a few different articulations. This is note C2, played on the 5th fret on the second bass string. They're played as noted: plucked, tapped, fret mute and different harmonics. This is stitched together (like I said, it's the first two seconds of each only), but clearly shows the relative amplitudes and times of each frequency heard for each note. Frequency/pitch are listed on the left, the top numbers are the seconds.

If you want to do this yourself, I used Sonic Visualizer to create the spectrograms. It's free software. http://www.sonicvisualiser.org/

Edit: Can anyone actually see/get the attachment? Let me know how else I can post it.

Hi Claire,

that's very interesting! (I couldn't see the attched picture inline, but was able to download it. Maybe it would work better with a JPG file.)

I find it interesting that with fret muting the first octave in the harmonics is much stronger than with regular playing. I didn't expect that.

Do you have a recording of the piece with spectral processing? I would love to hear that.

Cheers,
Johannes

I'm able to see that the attachments exist, but when I try to click on them nothing happens. Could be something on my end, but I don't know.

works fine for me through Tapatalk.

Can you explain this to a child? I don't quite get it, but I like the graphics. Did you have a audio clip? cool

That is very cool, Claire. Thanks for the link to the software, too: that will come in very handy soon after my Railboard arrives.

I can try…

I’ve attached a new image that will be easier to reference for an explanation. The audio file used is just a recording of tapping and holding the note C on my 2nd bass string at the 5th fret.

The top is a standard waveform, what you’re used to seeing in any DAW. It shows the amplitude of the sound over time.

The bottom is the spectrogram of the same audio file. It’s probably easiest to think of it as a three-dimensional representation of the sound. Like the standard waveform, the x-axis shows time (see the top ruler, in seconds). The y-axis shows the frequency content of the sound (the scales show both the frequency and a piano-style note representation). The z-axis is represented by the color and shows magnitude/amplitude. The brighter the color, the more energy there is at that frequency.

You can see the lowest part is the fundamental (correctly shown as a C). The rest show the amount of energy for each harmonic/partial (going up) - at the octave, 5th above, 2nd octave, M3rd above that, etc - continuing up the harmonic series. The spectral content of a sound is what allows us to differentiate between sounds that have the same pitch/loudness, to identify a sound’s timbre or tone.

The original image I posted is only the first two seconds of six different note articulations (noted as pluck, tap, mute, harmonic, etc). You can see how they are different in their spectral content, even though it’s always the same note.

I provided the link to the software I used to see this in the original post, it’s completely free and fairly easy to use. You can load up whatever sound files you have and see how this works for yourself.

Hope that helps.

In my best Peter Griffin voice:
"Dat...is AWESOME!!"

I downloaded it but I don't get these colors. I'll try it later though...

Hmm, a late thank you. I maybe get it a lil bit.