Jacob Lysgaard recently contacted me while he was working on building the Dub Siren I posted here and on Flickr. His documentation and description of the required parts, where he bought them, his findings, troubles, and experience while building it is far more informative than my images and flagrant plug for Bastard Jazz.

I’m happy to see someone has not only successfully built the dub siren but is finding use for it in their performance. All the best to Jacob.  You can find the post on his blog here:  DYI Dub Siren – the complete rubdown.

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But the tying thread is that they are usually just square wave oscillators with minimal tone and a couple controls to vary the speed and pitch of the siren. Check the sound samples at the bottom of the page for an example of this one.

This dub siren revolves around a couple of 555 timers and has four main controls. A speed control which changes the speed of the siren, a pitch control which changes the, well, pitch of the siren. A range control which changes the siren’s range and lastly, a modulator which, when engaged, alters the smooth sweep of the siren to a more asymmetrical ambulance type siren. There are two LEDs: one that flashes in synch with the clock cycle so you can see the speed in the dark and another that oscillates gently when the momentary switch is engaged. Both RCA and ¼” jacks are available and the RCAs are only active when there is not a ¼” jack plugged in. This was to prevent ground noise from accidentally coming into the circuit by inadvertent contact with the jacks. Check the full build on Flickr by the link below.

More photos, comments, and the schematic can be found on Flickr here:

SupersetSiren

Sound Samples:

Dry, without Effects

Wet, with effects