Ever wanted to recreate that classic Spring Reverb the old fashioned way?
We've made a super simple system with the DIY Speaker Kit and a few other items to create an awesome LoFi version.
Step 1: What You Will Need
You will need:
1 x DIY Speaker Kit
1 x slinky (miniature or standard)
1 x card board mailing tube (roughly twice the diameter of the slinky)
2 x foam board disks ( the diameter of the tube)
1 x foamboard disk (slightly larger than the diameter of the slinky)
1 x Piezo sensor
1 x Audio Jack socket (1/8 or 1/4 inch)
Hot Glue Gun
To use the Spring Reverb:
A sound source (keyboard/MP3 player/Guitar)
A output device (computer or Amplifier)
Step 2: Attach the Piezo to the Audio Jack Socket
Audio Jack Sockets are confusing at first sight, but not so hard to understand.
The Jack Socket needs 2 connections to make a mono sound signal:
Positive (Signal) & Negative (Ground).
The Sleeve of the Jack Socket should be wired to the Ground (negative).
This is the black wire on our piezo.
The end of the Socket that connects with the tip of the jack should be wired to the signal (positive).
This is the red wire on our piezo.
Solder in place for a secure connection. (at a push you can twist and tape, but this is prone to coming loose)
Step 3: Attach the Audio Jack Socket.
At one end of the card tube, mark and cut a hole the same size as the thread of the audio socket. Remove the nut from the audio socket and screw back snuggly into the hole.
Step 4: Attach the Slinky
Take the smaller disk of foam board.
Puncture a hole at the diameter of the slinky and thread it through.
Step 5: Attach the Speaker
Glue firmly the speaker exciter onto the foam board on the opposite side of the slinky.
Then onto the back of the exciter, glue on of the larger foam board disks.
Put the whole slinky/little disk/exciter/big disk sandwich onto the tube at the opposite end to the speaker socket.
Step 6: Attach Second End of Slinky
Hold the slinky end from the open end and gently invert the tube.
Take the second large disk of foam board.
Place the slinky end in the center and mark at the slinky's edge.
Make a hole here and thread the disk on
*DO NOT TWIST THE SLINKY AROUND, TWIST AND THREAD THE DISK DOWN*
If you twist the slinky, it will tangle into a horrible not half way down the tube, and unless you take pleasure in slinky detangling (which I oddly do) you DO NOT want this to happen.
Continue until the slinky has enough slack to move, but not so much that it slumps against the side of the tube. We want to hear the vibration of the spring, not hitting the wall or the speaker socket...
You should now have a tube sealed at both ends with a foam disk, and the slinky stretched between the two.
Step 7: Attach the Piezo to the Slinky
Glue the piezo onto the spring near the bottom of the tube.
We placed masking tape over the audio socket. If the spring makes contact with the audio jack, it will make an almighty racket in your headphones!
Allow the spring to pull the bottom foam board disk into place.
Step 8: Tape Down
Tape everything down lightly, (you may need to tweak the spring tension), and you are ready to test.
Step 9: Boost the Signal
The signal from the piezo will be too low to plug your headphones straight in, so you need to boost it with some software on your computer.
We used the free software Audacity to record the sound and add Gain to make the signal louder.
Plug your sound input (microphone/keyboard/guitar) into the speaker.
Plug the reverb unit into the computer through Audacity
Listen on headphones.
We just tapped the table in front of a micorphone with amazing results.
Simple wins the day.
Step 10: Decorate
Why settle for plain when you can have swanky.
We went thrifty and re-used some stuff (all be it pretty jazzy) that we found lying around the studio. Tape, old comics, stickers, sharpies, go crazy.