I am a graphic designer, so probably you could use another point of view.
When you are printing on offset you can prepare the design directly on a metal plate (direct to plate) or you can a high contrast film before preparing the plates.
Pre press High contrast film
Obviously, the machines are really expensive, but you can find a provider near you and the exposed and developed film is really cheap (I calculate that a 70x95cm is around $10 USD)
There are smaller sizes of roll film, and probably you can find a provider that can expose for example a 30cm strip by one m or more of film.
Preparing the design
Then you need to prepare your soundwave in the correct resolution. You can go as high as 4800 ppi in 1 bit images, but probably 1200ppi will be fine.
Use 1 bit images, if you use a normal grayscale image you can only use 300ppi and the result will be screened.
Then you can cut the strips using a normal cutter, and you can try to find a way to make the perforations.
This is the approach I would use.
If you want more detail, ask in the comments.
2001 space odyssey
Another method could be using a slit scan technique
which consist in exposing the film thru a slit.
You can probably construct a rig to slide the film behind the slit, and expose it using a normally led monitor shooting an animation...
There were rolls of 35mm film of 100 foot long strips, like Kodalith ortho 6556.
But I still would use the normal prepress film, which gives you an exact resolution and dimensions (therefore timing).
The disadvantage I think is the low resolution you will achieve, but if you want to invest money you could use a lens to shoot a very focused beam...
For the perforations
There is something called die cutting. You could have some troubles aligning the cut to the exposed film, but there are ways to work that.
The advantage of using a prepress film + die cutting is that you can prepare several meters of music and print them and cutting them in one step.
Do it on a backlight synthetic paper
There is a very specific type of material for backlight posters, that are printed on inkjet-based systems, the problem is that the plastic is not transparent, but translucent. But take a look. The cutting would need to be done the same way of the prepress negative.
Define your system.
Check some of ways sound has ben used in film history:
It has being using variable density, where you need bit depth, or variable area, where you can use lith film (high contrast)
If you can use the variable area aproach, you can use the prepress method.
If you need variable density you could construct something like this:
This can also could make variable area.
The problem is that any change in the rolling speed, will give you unacurate results.
I would stick to the digital print.