Make an ultra cheap and easy DIY clip and mic assembly for playing amplified rack harp for $5 or less!
Watch the video and then see the detailed instructions that follow!
Step 1: Materials and Tools...
1) 2-5 inches of 1 1/2" diameter plastic drain pipe
2) Gaffers tape or duct tape (preferably colored to match pipe)
3) An old or cheap tape-recorder mic, or a lavaliere mic. Dynamic element to be preferred over an electret condenser style
4) A harmonica rack and a harmonica!
1) Hacksaw or rotary tool (be careful!!!!)
3) "Step" drill bit
4) Soldering iron (may not be needed, depending upon your mic)
Step 2: Chop Down the Tape Recorder Mic.
Each mic will be different, but basically, you want to disassemble the mic and find the microphone element. Either remove the element, or cut the whole head of the mic off with the element inside. Try to get it as small as possible. If you had to take the wires off, solder them back on, or solder on a 1/4" guitar cable if the mic cable had a different style of connector. Use a lot of tape and/or shrink tubing to create strain relief where the cable attaches to the microphone element!!
Step 3: Prepare the "clip"
Use a hacksaw or other cutting tool to cut about a 3-4" length of your 1 1/2" diameter plastic drain tube. Using the hacksaw (or rotary cutter, be careful!!), cut out a 1/2" slot down the length of the tube. Take care to try to make the slot as straight and even as possible. You can use some sandpaper to smooth out any rough edges.
Using the step drill bit, drill out a hole on the side of the pipe opposite the slot. The hole should be big enough for your 1/4" mic cable to pass through. Again, you can sand any rough edges.
Step 4: Assemble the Mic to the Clip.
Thread the microphone cable through the hole, and position the microphone element inside the pipe, so that it faces the slot as much as possible. Secure the mic in place with gaffers tape on the outside of the pipe, over where the cable comes out of the hole. Ensure that the tape completely covers the hole.
Step 5: Clip on to the Harmonica Holder and Tape Up the Ends.
Depending on your harmonica rack, either first clip the clip onto the harp and place the harp in the rack, or place the harp in the rack and clip over both. Once the harp is in the clip, you can use more gaffer's tape to seal up the ends of the pipe. This will get you a more overdriven sound, but it is not necessary for the mic to work.
Step 6: Tips to Get the Most Out of It!
Watch this video to hear a the different sounds that this mic and clip assembly is capable of producing!
You may need an inline impedance matching transformer to change the mic's low-Z output to the hi-Z signal that your amp is expecting.
You can use a DI box, or a digital modeling pedal for similar purposes.
Experiment with using the mic and clip assembly even OFF of the rack. Using your hands on the ends of the clip, you can generate some insane overdriven tones!