These days, when you think reverb, you probably think about a guitar pedal or a plugin in your audio software. But you can also create reverb with a big metal plate and the right supporting electronics. [Tully] from [The Tul Studio] shows us how.
Basically, if you’ve ever smacked a big sheet of metal and heard the thunderous, rippling sound it makes, you already understand the concept here. To turn it into a studio effect, you use transducers to deliver the sound into the plate of metal, and then microphones to pick it back up again at some other point on the plate. Since the sound takes time to travel through the plate, you get a reverb effect.
[The Tul Studio] used a huge cold-rolled steel plate, standing one meter wide and two meters tall. The plate itself is hung from picture chain, which is strong enough to carry its weight. Old car tweeters are repurposed to act as pickups, while a larger speaker is used to drive sound into the plate. “The key to making it sound not like a tin can is the actual EQ and the electronics,” [Tully] explains, providing resources for this purposes.
We love lots of lovely reverbing things around these parts; oddball delays, too! Video after the break.
A digital echo plate would be more impressive
https://en.wikipedia.org/wiki/Delay-line_memory
So like running an FEA simulation of the metal sheet under stress and converting that to audio somehow… Would probably be interesting at least
Always thought a sheet reverb would sound better if the sound were launched and picked up in the plane of the sheet rather than perpendicular to it.
do both, the edge is going to filter out low freqencys from a driver, but could be better for a pickup, though the required hardware to mount a driver on the edge could also work as a dampner…..but once you have a chunk of plate suspended, the rest is easy enough to.play with
traditional plate reverbs have the ability to move drivers and pickups, so there is plenty to options, what could be interesting would be to hang the plate in a trough, that could be filled with water…..
The hot-gluing a bolt to a speaker to make the driver – that was novel! Some sort of epoxy or casting resin would probably work also.
In my working life, I had the privilege of maintaining a couple of EMT reverb plates. They had a similar-sized plate, but instead of just hanging, it was in a rigid steel frame, with tensioning clips all around. We used to joke that the tensioning instructions were: tighten a clip till it fractures, then back off a half-turn. High tension was important; it gave the plate that lovely high-end sheen.
The EMT also had a motorized “damper” which was a rigid wood sheet almost the size of the plate, which was on a sort of motor-driven pantograph that would move it closer to or further from the steel plate.
I recall an article 20+ years ago for a tensioned DIY plate similar to the EMT; the following link is close to those instructions, though the images currently seem missing:
https://www.prosoundweb.com/how-to-build-your-own-plate-reverb-a-concise-step-by-step-process/
Came home and posted after watching the Pacers win, oops.
The waves of energy are complex in the sheet, it don’t matter how you drive it. The suspensions should be longer. I really enjoyed the Moody’s reference, Darth’s voice wouldn’t do. MEMS mics would be most up to date. Those solid state pickups have two sides neither are ground, a little epoxy would insulate it go balanced out. Ground the sheet! I’d use tiny electret mics in the contact mode myself though, yeah two. Mono is so regressive, my surround sound didn’t register any space at all. There are mass drivers “my china cabinet makes beautiful sound”, TV ad for such decades ago. Search invisible speakers.
Sorry for the double post.