Listening.

May. 21, 2012 at 4:01pm

Concept - proven. Optimization - needed.

So I worked on the tin-can phone this weekend. Check out the pics. I don’t have any decent sound recordings but it doesn’t matter, because it actually doesn’t sound very good (yet!). But it did transfer something over the cable, which is encouraging.

shaft collars, steel cable

cans

Guy happened to be on campus with his visiting parents so I roped (cabled?) them into doing some testing…

“can you hear me?!”

“yeah.”

“how does it sound?!”

“tinny!”

yeah, it sounded tinny, and quiet. I sort of expected this. There’s a series of acoustic energy transfer points that are very inefficient (air -> can -> shaft collar -> cable. double and reverse that chain on the receiving side). Some ways to improve that include some kind of “stepped duct” system, where instead of coupling the bottom of can directly to the much more dense shaft collar, I can introduce a series of flat plates of increasing density and decreasing diameter, to more gradually step up to the density and surface area of the collar, and eventually of the cable.

Another issue, (see picture above) is the tensile strength of the can. I seem to have unlimited (for this purpose) tension capability via the ratchet belts. This is great on the one hand because the cable needs to be very taut.

here’s a recording of the string to demonstrate tautness

The weak link then becomes the can - the softest material in the chain. The can looks pretty stretched, although how close to breaking I’m not sure.

Some other non-acoustic issues, are about the physical interface of this thing. Ideally, there would be more space between the can and whatever it’s ratcheted to, and the tree, or whatever it is, should also be wider so that the belts are further apart, to better fit the source (mouth on head). Maybe a bigger can, but this of course complicates the acoustics part of it - bigger can bottom…

The other issue, and maybe this can be resolved with developing some kind of tin can protocol, is figuring out when to talk and when to listen. It took me and Guy a couple tries and coordinating exchanges via non-can methods to have an ear and a mouth on opposite sides of the line.

ONWARDS!

May. 12, 2012 at 10:53pm

Classes are done.

Classes are done, which means I will start posting more regularly again.

In the meantime, here’s some wind:

I’d recommend listening to this as loudly as whatever you have will allow. The thrill of being completely overwhelmed and gently brought back down by a gust of wind is unique.

Also, if you’re “into” “stereo”, at one point you can actually hear the wind pass through the woods from left to right. Like you always thought it did, like you never heard it do.

Summer!!

Mar. 9, 2012 at 1:42pm