Spring Reverb questions!

[Jazznoise]

Hey guys, been lurking here for a while for schematics and have finaly braved asking a question!  

I'm finaly doing some projects in Uni and since I'm getting the (majority of) components for free and we can make our own PCBs free also I'm looking at building some stuff this year.

Anyway, I've the bones of a spring reverb built - going to experiment with different spring gauges and speakers- its suffering major resonance issues atm. But the big issue is a volume drope. I was looking at the Super Hard On as according to ZVex's site it "drives" the pickup, which means I could pick up more signal in a less noisey way whilst possibly improving fidelity. Anyway, I was hoping someone might be able to tell me how right/wrong this idea is and possibly steer me in the right direction!

I was also looking at maybe having an attack/release and/or even an LFO for my reverb for some weirder sounds.

[tubelectron]

Hi Jazznoise,

I suggest you to visit the website of accutronics / sound enhancements : you will find informations about spring reverbs functioning and schematics to drive it correctly.

A+!

[Top Top]

What are you using as a pickup on the spring, and how is it attached?

That will make a huge difference in the amplitude of the output.

I recently built a spring reverb, there is some info/videos/pics in the link on my sig and also a thread here from a couple weeks ago if you search.

[Jazznoise]

Thanks for the links, guys!

I'm using the old amp circuit to drive the speaker (both from my first amp) which is attach to about 1 foot of a slink. It's help in place with a false paper cone I glued over it.

The pickup is literaly a guitar pickup (Ion strat single coil, no idea of the specs. It's merely what was at hand - I'd recently altered the guitar and swapped the bridge P/U for a Piezo). The spring is sitting between 2 of the coils so it is perpendicular to the motion. I don't really feel the pickup is the issue, I think the spring is just too heavy and doesn't really get excited enough by the pickup. Could I be cheeky and ask where you got your spring?

[Top Top]

The spring I used in the more recent one was from one of those "echo mic" toys. It is a plastic mic shaped thing with a plastic cup attached to a spring inside. I haven't been able to find any springs as light as that one at the hardware store.

Are you certain that your spring is magnetic? If it's not, then a guitar pickup is not going to work very well...

[Earthscum]

... I haven't been able to find any springs as light as that one at the hardware store.

Automotive store. Look at some of the throttle return springs. Usually you have one stiffer spring on the inside, and a lighter spring on the outside. They work together to dampen vibrations, but the outer spring is more for safety... back-up in case the main spring fails. It doesn't have much tension at all so you can "feel" something is wrong, usually large coils, small gauge wire. Not sure on what length you need, but they should be about 4-6 inches with tension.

I also saw one made with a metal mini-slinky... well, a section of it, anyways.

My idea is to make a half scale string tension setup on a wood frame and use one of the sets of old strings I have. Then a guitar pickup would work great (I have an old humbucker that I'm thinking of using). Also, could dampen individual strings, and tune them for desired resonance. Almost like an electronic controlled sitar, if you will... more of the sound I expect from it.

[Top Top]

... I haven't been able to find any springs as light as that one at the hardware store.

Automotive store. Look at some of the throttle return springs. Usually you have one stiffer spring on the inside, and a lighter spring on the outside. They work together to dampen vibrations, but the outer spring is more for safety... back-up in case the main spring fails. It doesn't have much tension at all so you can "feel" something is wrong, usually large coils, small gauge wire. Not sure on what length you need, but they should be about 4-6 inches with tension.

I also saw one made with a metal mini-slinky... well, a section of it, anyways.

My idea is to make a half scale string tension setup on a wood frame and use one of the sets of old strings I have. Then a guitar pickup would work great (I have an old humbucker that I'm thinking of using). Also, could dampen individual strings, and tune them for desired resonance. Almost like an electronic controlled sitar, if you will... more of the sound I expect from it.

I've actually had a throttle return spring break on me, so I know what you are talking about  

It cost me the clutch in my car as letting it out was the only way I could think of quickly to get the engine to stop running away (it is a diesel and shutting off the ignition was not working at that engine speed).

Anyway... back on topic. The spring I ended up replacing under my hood was still pretty heavy. Heavier than the one in my mini reverb now.

I actually built a resonant strings reverb sort of like you mention, or rather I built an electric zither and included a pair of exciters to make it into a sort of sympathetic strings reverb...



It works ok... It would be interesting to see how it would work on lighter gauge strings at lower tension. I think sympathetic strings generally are lighter than the ones I have on there.

[Jazznoise]

That zither is absolutely amazing looking  My ears would like to hear it very much.

How much would we be talking for one of those Throttle Return Springs cost ya? I've been alerted to a Spring manufacturer near my university, but I don't really feel I know enough about K values etc. to approach them.

[slacker]

There some good stuff about DIY spring reverbs here http://www.electronicpeasant.com/projects/springs/springs.html, well worth checking out the rest of the site as well, loads of interesting stuff

[petemoore]

http://www.electronicpeasant.com/projects/springs/motortrn.gif

A DC motor becomes a pickup...interesting.
 

[Earthscum]

Hey! Nice, slacker... that's the one I was talking about! Slinky...

I forgot about my other idea I had whilst digging through springs at Ace... there were a bunch of springs that could be mounted at just one end, driven from near the mounted end, and exciting a coil at the other. They had decent decay in my hands... would probably benefit from a bit of dampening once mounted. These looked like stretched out heavy springs, basically. There were a few with smaller gauge wire that really seemed to have potential for a reverb.

I love that zither. I just got a couple of those transducers and a couple TDA2822's to drive them with (for now). I may have to steal that idea... although I'm gonna try it with bass strings. Should be easy enough to remake a bridge and nut if they don't work out right... I'm handier with stuff like that than I am with the electronics part.

petermoore... not sure if it's on that site or another, but you can also use the motor as the driver in the same way.