I want to explain what I mean in the form of images, because i think that makes it easier to understand.
Classical Wavetable Synthesis
Normal wavetable synthesis wirks by scanning through a wavetable. The wavetable can essentially be seen as an image or a rectangular cut out of a terrain - it has mountains and valleys. The Terrain/Image has two coordinates x and y which in the wavetable are called time and "wavetable position". Normally we have a knob with which we set our wavetable position while the software is scanning through it. It is essentially walking in x-direction over the terrain and instantaneous jumping back to the starting point once it has reached it's endpoint.
The wavetable scan is essentially a "path over out terrain". Why not change the pathes even more? I was thinking for example about a circular path over the terrain. Or think about a lissajou-shaped path it you'd like. This would have the advantage that start and endpoint are the same - no need to equalize wavetables (in order to avoid non contiuous jumps if not desired).
image as wavetbale
fancy 3d graphic
- the radius of the circle can be changed (and controlled with CV).
- the x and y position of the circle midpoint can be moved.
- the circle can be stretched
- special behaviour at edges can be defined (if the circle would scan outside of the wavetable/terrain because the radius or midpoint have certain parameters. The behaviour could be a Modulus, Contant or Mirror (this is derived from texture filter stuff in 3d-graphics).
The scan coordinates can be changed over time from a circle like this
This Idea can be taken much further. For example in irder to create stereo sounds easily, Left and Right channels can scan different colour-channels of an image. I think this could be very interesting, since the cannels often have similar "structure" but are different on certain position (e.g. a white object is similar in all channeld, but a yello one not, a picture can contain white and yellow objects at the same time..).
For stereo-scanning the channels can be mixed.
wavetable synth by camera (+crazy ideas)
This is of course pretty crazy, but a modul could be created, that uses a camera in order to create these wavetables in realtime. Of course in this case a real camera wouldn't actually be necessary - a very fast slidscanner would be enough for a simple implementation.
And this could even be used to create a truly analog wavetable synthesizer! Old CRT Monitors are essentially doing the reverse of wavetable scanning - they display wavetables. They scan through it up->down and put one line on the screen from left to right. The amplitude is the brightness or the amount of electrons colliding with the phosphor of the screen. The same prinziple could be reversed!
Think of a photodiode that is converting brightness into eectricity. If that photodiode would only detect light from a very narrow direction (put a very narrow tube before it) the line of sight could be moved by a fast spinning mirror-prism. e.g. this laser projector has a prism that makes this possible.
This way the wavetable could be changed by moving an image through the scanned slid. The brightness over time would be the amplitude of the wavetable. (of course the frequency of the sweep would be hard to change quickly if we use a rotating prism - a very small moving mirror is also possible and used in some laser projectors).
edit:i just found this on youtube - it is in a fundamental way one part of it. altough it is not "scanning" any table, but rather just sampling the same position over time.
What do you think? I didn't really know where to put this. It is more a general discussion about wavetablesynthesis and the approach of it.