DIY SPRING REVERB

[phantompowers]

DIY SPRING REVERB

This is my first experiment with this classic effect and I can't believe it actually works!!!
Firstly, I made a mini-guitar amp circuit from instructions found on the very informative Beavis Audio Research Site -

http://www.beavisaudio.com/bboard/projects/bbp_CigaretteAmp_Rev1_1.pdf

This circuits output is a small speaker. I attached a large spring to the paper cone with candle wax. The other end of the spring has a piezo disk attached to it also with candle wax. This is amplified through a small guitar amp.

I wouldn't advise anyone to actually use wax, as it was very hot yesterday and started to melt! Get some PVA or hot glue on it instead.

[Matt the Modulator]

NICE WORK i tried to use a piezo as the driver and one for the pic up but could never get the spring to stick

[Circuitbenders]

Thats one of the stupidest things i've ever seen, good work. 

In fact its so ridiculous i've just had to post it on the circuitbenders facebook.

[phantompowers]

Hahhaha! Nice one. I've just seen the post on Facebook.

When I first got interested in a DIY reverb unit, I thought that the spring was part of the circuit, i.e had a current running through it. But no!!! It is all about miking up the springs vibrations, or 'reverberations', and then mixing the wet and dry signals together to create the effect.
I hoped this video would clarify that aspect of reverb and inspire more people to attempt their own version.

I've just remade it with PVA glue instead of wax and it doesn't sound as good. I think the PVA has muffled the speaker cones vibrations.

I've made a wooden box to house it in but I'm having problems with the wiring. I can't figure out how to control the reverb mix with the dry signal. Any sugestions?

By the way Matt, I was very inspired by your reverb unit.

[Circuitbenders]

I'd imagine that PVA will just act to damp the vibrations as its pretty rubbery and soft when its dry. You probably need a glue that dries harder and more brittle like wax.

Can't you make a wet/dry control using the output from the spring and the straight signal wired to either side of a pot, with the centre pin as the output?

[phantompowers]

Yeah, I reckon you're right. I think I'll go back to the wax.

I did try your sugestion with the pot initially but it didn't work. I may have wired it wrong due to the mass of crocodile clips confusing my brain. Would a pot of any value work using one like this?

[Circuitbenders]

i'd probably start with a 10K and work from there

[JohnnyLongarms]

DOING IT!!!

[adamduke]

this is totally awesome.  I'm definitely making one!  or two!  I have a bunch of speakers lying around already...  suppose you use a full-size slinky in a large, foam-padded box for better output quality, yeah?  What about mounting the top of the spring on a sliding bar....how much would that affect the sound do you figure?


I'd bet these little guys would makes a nice xmas presents for my musician friends!!  Great post!

[samspike]

Has anybody had a look at a (dead) guitar amp?  Because maybe I'm thinking their might be some applicable lessons from them.


Years ago, I took apart an old dead guitar amp.  The spring reverb that I extracted from one actually had 2 pretty stiff springs (stiffer than those in an electric guitar's tremolo system) in a rigid metal box (like 1/8" thick steel I think).

I can't find the bits anymore (it was a few years ago I did this) - but I will try to find them as I don't think I tossed them.

[moordenaar]

I'm currently making one. Just need to wire it up, and align my actuators.

And it's a far bit more complex than what you made there.. I'll finish it as soon as possible.

[moordenaar]

Need to make a decent amp for it.

[untune]

@moordenaar

It'd be cool to see some pictures of what your working on, or at least a bit more of an in depth description at least   As for amps, what about modifying a velleman kit?  Someone made a DIY spring reverb on here using them if I remember correctly?

[moordenaar]

Sure I'll put some up later.

[untune]

Awesome, really looking forward to seeing it!