Rubber membrane footstomp
Hi folks.
I just wanted to share with you my latest project. A rubber membrane footstomp. I haven't seen anyone here trying this before so I thought I'd share this. There are some stompers out there that uses a membrane and those got me inspired to try my own. I felt that I needed to build a stomp and I wanted, just like everybody, to have it as bassy as possible. Don't know what this one sounds like in comparison to other variants but I'm pleased with the outcome. I'll try to add a video so you can judge by yourselves but please do listen to it via headphones. I think that'll make it the best justice. I did also do a comparing video with a low budget old bass drum. But the sound quality of that part isn’t very good.
I built this with bits n pieces lying around. The main idea was to use a sheet of rubber for membrane and make like a small drum. By adding weight to it I could make it to vibrate slower and more bassy. The rubber sheet is also quite thick. 2 millimeters. The pickup is a humbucker from CB gitty and it's connected straight to the jack. The construction enables me to "tune" the membrane by tightening the screws on the middle board which pushes the cookie tin lid upwards and the membrane gets more tension. While experimenting with this I discovered that the sound was very much improved by making air holes in the lid. By doing this the membrane could vibrate freely. Without holes it just produced a short sharp sound. It was quite a quick build and I guess one could develop this further and improve it a lot. I've added a sketch and some pictures of the construction below.
/Emlas
And a video... I hope I succeded in ataching it. Otherwise you can watch it at my page.
http://www.cigarboxnation.com/video/stompbox
Find more videos like this on Cigar Box Nation
Replies
Nice sound.
Thanks emlas, Darryl.
The additional information will be helpful. I have several ways to go with the container. I didn't know about the magnets. That's important info.
I'll post whatever I assemble and let everyone know what I find.
Thanks again.
I've been trying to design and build a good (say deep) stomp box for a while. Tried Piezo, single wound, humbucker, 3" speaker, etc. Most just sound like short, sharp "thuds". I thought about some kind of rubber surface that would produce a low sound with a little less sharpness in the decay. My rubber arrived today as I was reading your post (timings everything).
So, I'm ready for another go at it and your design looks very good. A few questions.
1. What is the purpose of the cookie tin lid? Is it just to space the rubber correctly
2. How much clearance are you leaving between the rubber and the pickup?
3. On the drawing, there is something written above the bolt in the center of the rubber. What does that say?
Thanks.
I'll post my results when I get it going.
Ithink it's neo magnets Tom,attracting the washer under
Those are neo magnets.
It will be very interesting to see what you'll come up with!
1)
The purpose of the tin lid is to get a nice rim for the rubber sheet to rest on and also to be able to get some tension to the rubber. The lid presses the rubber up through the hole. The lid is mounted on the middle board that's suspended on four screws. If I tighten the screws, the board and lid presses upwards and the rubber gets more stretched. The rubber itself is attached to the upper board, the one with the cutout. I also grounded the lid while I was at it.
2)
Well.. I don't really know but I mounted it so it could be adjusted. Tried to get it as close the washer as possible.
3)
There's no bolt in the centre. It should probably work fine with just the washer and perhaps some bolts but I glued a couple of neodymium magnets to the top of the membrane.
The text reads:
Neodym magnets (glued)
I didn't do much of research and optimising on this build. I just went with the flow an it turned out pretty well to my simple ears and low expectancies. I hope your box will be fantastic!