URGENT HELP NEEDED FOR SCIENTIFIC RESEARCH - Creating a simple beat

Hi everyone :slight_smile:

I just downloaded Audacity, so I’m a complete beginner. I’m currently doing a master’s degree in biology, and I’m working on the behaviour of black widow spiders. I know it must be an unusual use of this software…

I would like to create a vibratory signal I can play with a speaker on the webs of my spiders. Right now I’m simply using the Tunable app on my phone to play different notes, corresponding to the frequencies I’m interrested in. Now I would like to complexify my signal, by varying the amplitude (volume) during the signal.

So I would like to create a simple beat. The ideal end result would be a patern (for exemple : 3 sec at 50 hz, 1 sec silence, 3 sec at 50 hz, 1 sec silence, 3 sec at 50 hz), with the same note (frequency) I could change. The tricky part (or not) is that I would like that during the 3 sec the note is playing, the amplitude (volume) would increase or change. It can be a little chaotic, as long as I have a recording that I can play always the same way. Should I create this beat or is it simpler to record something ?

Do you have any tips on how to approach this ? If I don’t find a solution very soon, I would have to abandon this idea.

Thank you so much for your time !

Stéphanie

I think we can get close.

Open Audacity.

Generate > Silence > 3 seconds > OK.

Computer END key.

Generate > Tone: Sine, 50Hz, 0.7, 3 Seconds > OK.

END

Generate Silence again,

End

Generate Tone again.

That should give you the following display. If you play it, it should be Silence > MMMMMMM > Silence > MMMMMM.

Screen Shot 2022-01-20 at 5.47.05 PM.png
Click inside one of the tones and select the Envelope Tool (two black arrows and bent line).

That will let you drag the volume (blue wave height) up and down over time.

Screen Shot 2022-01-20 at 5.59.57 PM.png
Seems pretty easy, but there is a caution. There may be a tick or pop each time you go into or out of a tone. This is where good headphones or speakers will be handy. 50Hz is not easy to hear, and very few sounds in nature start at full volume instantly and then stop dead. You may not care about that.

I’m doing these tricks in Audacity 3.1.3.

https://www.audacityteam.org/

Koz

One more note.

When you get exactly what you want, Save an Audacity Project and Export a WAV (Microsoft) 16-bit sound file. The project should let you modify the character of the waves, but Projects can be a little brittle and you need Audacity to play it. WAV files are more robust and they should play anywhere on anything.

Make both and they can be backups for each other.

Audacity 3.1.3 also has File > Save Project > Backup Project. That will give you a stand-alone Audacity Project with no strings or connections back to the original production.

Koz

It’s working ! Thank you so much :slight_smile:
Now I will try to see if spiders can learn, a very little studied subject !

Now I will try to see if spiders can learn

Teach them how to use the world wide web. :wink:
(Sorry, couldn’t resist).

Interesting concept, wonder if they just do things automatically or do have the ability to learn?
Do they have any capacity for memory retention?
Just please don’t post any spider pictures… :astonished:

If you’re trying to listen to them, see … https://youtu.be/y7qMqAgCqME?t=101

Just one last question ! How can I change the frequency of the tone after it’s created ? Because I want to copy paste the tone so the patern is the same but create 1 file per frequency.

Thank you !

Select the “performance” > Effect > Change Pitch.

Cautions:

– Make sure you keep perfect copies of the original work, both Project and WAV. Save them somewhere safe. There’s just nothing like having Audacity take a dive and destroying both the new work and the originals.

Select a copy of the Project and Effect > Change Pitch.

Always work from copies of the original masters. Don’t make new versions from copies of the last versions and copies of the ones before that.

Two effects, Change Pitch and Change Tempo cause distortions and you can’t stop them. It may not matter to you or the spiders, but the very best results are to start over with fresh tones at the new pitch/frequencies.

You’re going to ask if there is a way to copy just the envelopes. I don’t know. That’s up to more senior elves.

You’re also going to ask why do those two effects cause distortions. Those two are compromises between getting a workable effect and waiting for them to complete. It doesn’t matter if they do a perfect job if they won’t be done until after the sun cools off.

Koz

Apparently spider researchers use frequency sweeps … https://www.cell.com/current-biology/fulltext/S0960-9822(16)30985-X
(they did have electrodes in the spider’s brain at that point to measure its sensitivity to the vibrations)

Audacity can do that via Generate, Chirp.

You can use this “Nyquist Plug-in” to generate the patterns.
PulseBeat.ny (862 Bytes)
Installation instructions for Nyquist plug-ins: https://manual.audacityteam.org/man/installing_effect_generator_and_analyzer_plug_ins_on_windows.html#nyquist_install