Blood_mountain wrote:In your experience, is there anything else one can do with a tank to change the sound? What about other devices to drive sound through?
In my experience, tanks are pretty optimized to their purpose. I may be guilty of a preservation bias though, as I tend to try and leave existing systems intact (read as: I have a pile of decades old shit that I don't want to break, not that I shy away from the pioneering spirit). So, I'm going to focus a bit on the second part of the equation here.
Blood_mountain wrote:What about other devices to drive sound through?
Let's start with a complete sidetracking rabbit hole and mention in passing stuff like the Cooper Time Cube which uses a small speaker to push sound through a length of tube with a couple microphones doing pick-up duty.
Forgive me a moment of pedantic set-up here.
The above system, like the spring reverb boils down to five parts:
1) amplification stage to drive a transducer.
2) transducer (consuming electrical energy to create mechanical force or zones of high/low pressure)
3) delay line, or any object or medium through which the mechanical/acoustic force can travel
2) transducer (producing electrical energy as a result of mechanical force or changes in pressure)
1) amplification stage to fortify the signal into something ample enough to hold its own with respect the rest of the mayhem you've got going on at any given time.
Cool, so the reverb spring produces rotational force or side to side wiggle (being that it is moored on one end of the transducer that's the limit of non-destructive movement available) that subsequently wiggles a magnet inside of a winding to induce current.
That particular driver set-up is difficult to DIY, but thankfully we've got stuff like
tactile transducers or small speakers to work with. These can interface with a Slinky, sheetmetal, hoses, etc. pretty well. Hung wire (under tension) also carries vibration quite well, and setting up a tactile transducer on a small metal plate that the wire is tied to can result in useful signal that only needs to be collected.
Collection transducers can be as easy as a piezo element clipped to the delay medium, or you could pull a "tin can telephone" and feed a mic.
Everything is really bulky and increasing lofi in my brain right now.
Something I've been meaning to try for a while is slapping a transducer onto a barrel of water, and then dropping a hydrophone into it; or conversely dropping an underwater speaker into a barrel or trough of water with a contact microphone on its side. It's the part under the water aspect that is slowing my brain enough to keep it on the drawing board beneath piles of other shit.
Anyway, the point of my rambling post is that all these amount to little more than five components, many of which most of us already have. Headphone amplifier stages drive most anything, and any gain pedal is usually enough to make the small signals big again. From there it's just stuff and shit. Piezos and exciters can fill in the blanks.
As an aside, one of the "transducer domain change" experiments I intend on doing before I die is to mount a compression driver or speaker in place of a carburetor on some old engine, plumb the spark plug holes and exhaust ports into some varied mess of tubing that interfaces with a variety of collection transducers, and then turn the engine slowly with an electrical motor while blasting sound into the intake manifold. I figure it will be a terribly heavy, lossy, and fun modulator of some sort that I will hurt myself with while hauling it to a gig.
Hope that helps!
