Small Tube Bedroll with Big Sound

Small format Tube Stereo with oversize speakers

A customer requested a small bedroll speaker to fit behind their windshield on their cruiser. The goal was to keep the overall length of the bedroll speaker below 16.5”. This allows mounting to the handlebars and fit behind the full coverage windscreen.

Starting with a four inch PVC tube cut to fourteen inches and machined it to fit the four inch high overlap baffles. These baffles are designed to slide over the serape (Mexican blanket). I then decided where to put the penetration for the speaker wires. Due to the size of the customers amplifier I was not able to fit it into the tube so speaker wires will need to exit the back of the tube. A three eighths inch diameter hole is drilled and generously chamfered.

The tube was cleaned and then used to trim an adhesive backed foam sheet and size the serape. Wrapping of the tube with the foam is not critical but this provides a nice touch feel and a better bonding surface for the serape open weave material.

Once wrapped with the foam and smoothed down the surface the tube is sprayed with contact cement. The back surface of the serape is also given a light coat of adhesive. After waiting ten minutes for the adhesive to be dry to the touch the serape is applied to the tube. Care must be taken to ensure that the lines of the serape follow the center line of the tube and that any features in the weave fit the tube geometry. Gently rub the serape over the tube and then let the fabric cure for several hours. Excess length of the serape can be trimmed.

Baffles can now be slid over the ends of the tube. Both baffles can be slid over the serape and screwed into the tube ends.

Speaker wire can be run into the tube with enough length to reach the amplifier. The speaker wire can be soldered to the terminals of the speakers (this eliminated the wires coming loose from the spade connectors). The speakers now can be attached to the baffles on both ends. Speaker wire can be drawn into the tube leaving a small about of slack.

The system is ready to bench test and then mount onto the motorcycle!