lofi reverb pedal using tiny speaker, spring and single coil experiment

[iainpunk]

i have a bunch of tiny (32mm and 26mm) 1W 16Ω and 32Ω speakers and some fairly slinky springs from a microwave, so i was wondering if it would be a good idea to make a lofi speaker driver WITH crossover distortion, glue the speaker to the spring and pick up the spring movement with a guitar pickup (am i the only one with like 8 or 9 single coils laying around?), mix in the reverb signal with the clean signal and then add some crossover distortion, highpass, lowpass and 'vibrato'. (yes vibrato after reverb to get to lofi heaven)

any suggestions/predictions? i'm not sure yet if it's going to work, and i hope it's getting me in to lofi heaven.

cheers,
Iain

[Digital Larry]

I like spring reverbs in general, so I think it's a great idea.  Not sure about crossover distortion but if that is what you like, then go for it. 

Be interesting to see how a guitar pickup would respond to a spring.  AFAIK most reverbs detect the "torsional" (twisting) wave motion which is probably not what you're going to detect by putting a guitar pickup near the spring.  I'll suppress the urge to endlessly pontificate. 

Do it!  Do it now!  Report back!   

DL

[FUZZZZzzzz]

use slinkies!

[iainpunk]

im building a lofi machine, crossover distortion is kinda required, the spring isn't very long and/or fine like a normal reverb spring,  it came out of a microwave, i think it is a heater, since it has electrical spade connectors at both ends.

i am aware of the torsion motion reverbs use, but really old types used expand/retract motion and worked fine as well (despite having a shorter decay for the same spring length).

i am also curious about the pickup sound compared to the angle to the spring, i predict that 90 degrees sounds best, but if that doesn't work, i'll use another little speaker, i know they work as contact mics. (they sound way better than piezo elements in cigar box guitars)

its gonna have vibrato, soft single sided clipping and bandwidth limiting filters after the reverb anyways, its going to be a big lofi box with a bunch of lofi stuff in it.

unfortunately its taking until tuesday before i can experiment again.

cheers,
Iain

[soggybag]

What does the spring do in a spring reverb?

I've always thought where the coils made contact shortened the distance the signal would travel through the coil. Is that right?

[iainpunk]

What does the spring do in a spring reverb?

I've always thought where the coils made contact shortened the distance the signal would travel through the coil. Is that right?

no,
there is a motor and transducer (dynamo) at the beginning and the end of the spring, the signal goes through a power amplifier and in to the motor, the motor translates the sound to motion, the spring delays and reflects the motion back and forth, but is slowed due to air resistance, creating the wash's decay time (vacuum reverbs have way longer decay times), the dynamo picks up the motion and transforms it into a voltage, which is mixed in with the clean signal. there are multiple ways to move and pick up the spring, you can use speakers, actual dc motors and even piezos.

cheers,
Iain

[PRR]

> where the coils made contact

Turns should not be in contact.

[anotherjim]

Someone was looking for a source of long close-coil springs - then I thought of plate hangers.

[iainpunk]

Someone was looking for a source of long close-coil springs - then I thought of plate hangers.

really nice idea, those are some longass springs there.

so i had contact with a friend of mine, he's a modular synth guy, and he told me of a spring reverb with piezo discs glues in between turns, so he had a 12 tap spring reverb, which sounded really lush according to him, might try that out myself.

how about instead of mixing the clean with the reverb, we ringmod them together... hmmmmmm

[snufkin]

the thing you want is a very light easy to drive spring, while not the only source, those toy passive echo mics have a great spring inside them for this http://thesquarewaveparade.com/2dlrsprng.html

you can use a piezo as a pickup and a tiny speaker/headphone speaker as a driver, you can even cut out most of the speaker cone if you want to minimise it's sound making during operation.

there are a few old threads about similar projects on here