How to Build a Rotary Speaker

Rotary speakers were originally used in organs, but were later integrated into guitar amps.

Rotary speakers, often called Leslie speakers, create a swirling sound effect by spinning around and around. There are two plastic cones in a Leslie speaker that focus the sound outward in two opposite directions, creating the effect. Building your own rotary speaker is a relatively simple process for many guitar enthusiasts. It requires a basic knowledge of building information as well as a basic understanding of speaker technology.

Things You'll Need

• 2 large plastic funnels
• Tape measure
• Small guitar speaker
• Pencil
• Electric hand drill
• Sand paper
• Electric tape
• Turn table
• Empty guitar speaker cabinet
• Electric splicing kit

Instructions

1. Place the narrow ends of your plastic funnels together, holding them together at the ends. Have a friend hold the funnels together as you work with the guitar speaker.

2. Measure the distance around the narrowest section of the speaker, where the cord comes out the back. Draw a circle of this size on the funnels where they connect, with one half of the circle on each funnel.

3. Mark a small circle on your funnel about the size of your turntable rod. Make this near your speaker but far enough way to avoid hitting the speaker.

4. Drill away the plastic from the circle halves and from the turntable rod hole. Lightly sand the ends to remove any plastic splinters.

5. Put your speaker inside the hole and push your funnel halves together. Wrap tape around the funnels where they connect to hold them together.

6. Slide the turntable rod through the turntable rod hole and tape the funnel to the turntable rod to hold it in place. Make sure your funnels are evenly parallel with the turntable.

7. Open the back of your guitar speaker using whatever screwdrivers are necessary. Place your turntable inside the cabinet in front of the speaker mesh. Make sure there is enough room for the funnels to turn without hitting the sides.

8. Scrape the plastic away from your turntable power line and your amplifier power line and splice the lines together. Wrap your electrical tape around the wire to hold them together.

9. Find the turntable input line and splice that with the input line of the speaker. These lines will vary depending your turntable and speaker. Consult your manuals if necessary.

10. Plug in and turn on your amplifier and your guitar. Turn on your tur table and set it to the speed you want it to spin. Play your guitar to get the rotary effect. Adjust your wire splicing if your sound has static or is choppy.

References

• Mantor: DIY Leslie Speaker
• Stefanv: Adding a Rotary Speaker to a Hammond M-111
• CYR Guitars: Leslie Construction Project