The DIY orchestra of the future – hemi speakers

In this TED Talk Ge Wang of Stanford geeks out about computer music (hooray!). He talks briefly about the hemispherical speakers used by the Stanford Laptop Orchestra. Their design (using an IKEA salad bowl) informed my hemi speaker experiments here.

I recently bought a 6-channel amplifier to upgrade the 3 2-channel amps I originally installed in the speaker. I’ll post about the new amp as soon as I drop it in.

Hemi Speaker and Our Lady of Detritus

I recently had the opportunity to help Kristin Norderval build a hemispherical speaker for use in the jill sigman/thinkdance production, Our Lady of Detritus, engagingly described as “a portable, interdisciplinary performance installation about trash and transcendence; a traveling grassroots campaign fueled by experimentation, green energy sources and community interaction.” The show is presented every weekend through mid-October at various locations around New York City. See here for details.

The speaker was based on the Princeton Laptop Orchestra (PLOrk) Delorean speaker and the Stanford Laptop Orchestra (SLOrk) speakers.

Enclosure

We used an Ikea salad bowl for the enclosure just like the SLOrk speakers.

Amps

We pulled 3 Dayton T-amps from their enclosures and mounted them on the inside of the bottom plate of the speaker cabinet.

Speakers

We used 6 4″ Inifinity 4022i drivers.

Volume Pots and Connectors

The Dayton amps had combination volume and power pots, so we decided to keep them rather than source and wire up a 6-position potentiometer. A little Dremel routing magic made mounting the volume pots easier than I expected. A coaxial power jack and 6-pin Neutrik XLR jack and plug rounded out the connectors.

The speaker sounds good–punchy and more powerful than I expected, particularly considering the 4″ drivers. I’ll be building one for myself soon.