The most surprising gadget in my gig bag is a battery-powered speaker called the Wowee One. It’s about the size of two stacked iPhone 5s, turns on when you plug in an audio cable, and pumps out an astonishing amount of bass. The secret is a secondary transducer that sends low-frequency vibrations through a gel pad on the bottom. Held in your hand, the Wowee blares harsh midrange tones. But place it on a resonant surface like a box, coffee table, or fried chicken bucket, and it transforms the surface into a thumping woofer.
Part of the fun of vibration speakers is trying them on different surfaces. The loudest surface in my house turned out to be my son’s air hockey table (see Fig. 1). As a sound designer, I think of vibration speakers as novel distortion effects, so my next experiment was to feed a drum loop through the speaker and sample it while powering up the table’s fans. The whine of the motors ramping up became a unique riser sound.
Vibration speakers can also sonify other objects. Fig. 2 shows an electronic tambourine I made by arranging coins on top of a Charzon ChaCha. With a more powerful speaker like the Wowee or an over-the-top tactile transducer like the ButtKicker (thebuttkicker.com), you can create gamelans of jangling junk. Try placing a vibration speaker on top of a washing machine and capturing the sound of flapping sheet metal. You can get radically different textures with a handheld recorder inside the drum versus a contact mic on the side. Gently clamping the speaker to the surface or placing a heavy object on top of it produces stronger bass and interesting filter effects.
One of my favorite instruments is the Korg Wave-drum, which transforms acoustic vibrations from the drum head into otherworldly electronic sounds. Because I’m more skilled at playing a keyboard than drums, I decided to make a remote control. I plugged my Novation Bass Station 2 into the Wowee, placed the speaker on the Wavedrum, and played rippling streams of notes (see Fig. 3). Adjusting the Novation’s envelope decay and filter frequency changed the composite sound from dusty melodies to flammed digi-drums.
I’ve used vibration speakers as compact monitors when playing live, because they deliver so much sound per pound. Vibration speakers can also add an almost acoustic resonance that makes electronic instruments feel more alive and responsive.
When I place my Wowee on my digital piano, the keys feel more organic, as if actual strings were vibrating inside. Sticking it to the back of an iPhone or iPad transforms taps on the glass display into a tactile performance. I paid $20 for the ChaCha; the Wowee runs about $50. These cheap vibration speakers sound awful for music, but as feedback devices they add a truly special feel.