Nyquist Code for Multiplying Ch. A with Ch. B

Programming and Development Nyquist
1

Would someone be able to please advise me on the correct Nyquist code for multiplying channel A with channel B?

The intended effect is similar to analog multiplication of X and Y inputs using an IC such as an AD633. It results in changes to both amplitude and pitch.
This is different from standard modulation or mixing functions.

Thank you for your reply.

2 
;version 4
(mult (aref *track* 0) (aref *track* 1))
3

Isn’t that what Vocoder does? It combines two different instruments or voices in such a way to produce modulation.

https://www.youtube.com/watch?v=YR_Bjf-a5rs

Koz

4

No, a vocoder is different. See: Vocoder - Wikipedia

5

When I debug the code suggested above in v 2,1,2 in MX Linux I get this error message. Clicking “Preview” does nothing as well. Track i is 10s brown noise. Track 2 is 10Hz. Please advise solution.

error: bad argument type - #<Sound: #57a85710>
Function: #<Subr-AREF: #575cf018>
Arguments:
#<Sound: #57a85710>
0
1> error: bad argument type - #<Sound: #57a85710>
Function: #<Subr-AREF: #57d88de8>
Arguments:
#<Sound: #57a85710>
0
1>

6

You need to join the two mono tracks into one stereo track before you apply the Nyquist code.
See: Splitting and Joining Stereo Tracks - Audacity Manual

7

Thank you. It is working now. For users of older versions, the “make stereo track” command is located not in the top menu, but within the box to the left of each track. Click on downward pointing arrow.