Workshop: DIY Electric Melodica

Don't mind the stickers on the keys -- they're for my kids!

Ever since grabbing a melodica for the house, I've wanted to figure-out how to plug it into a guitar amp so I could get some "blues harp" vibe from it. That's a challenge, though -- melodicas are not the easiest thing to mic-up and contact pickups can be troublesome, especially if they're surface-mounted.

I'd looked at what people were doing on the net -- often using 1-sensor K&Ks or cheapy-cheap disc sensor pickups and sticking them to the back. I figured that would give an unbalanced sound -- and it does...!

So, rather than penny-pinch, I bought a K&K 4-big-sensor upright bass pickup ("Double Big Twin?" or similar name) which cost more than the instrument itself -- and if I didn't like the sound I knew I could always move them over to some different use around my herd of instruments.

I figured I could spread 4 sensors out along the sounding board (which is: the back of the instrument directly under the reed plates) and get an even response.

The short of it is that it works nicely, though you definitely hear body noise, handling noise, and clunks from the keys if you're not careful. However, I think in a recording (or live), none of that would be obvious or noticeable at all over the clatter of whoever else you'd be playing with or whatever else you'd have on your track.

So -- here are the pictures of how I rigged this up.

1. First I located a place where a jack could fit (and have room for the 1/4" input to travel into it) and also a place for a volume control to fit.

2. I then cut the sensors away from the original jack for the 4-sensor K&K pickup. I glued them (gel superglue) equidistant along the back of the body and directly under where the reed plates sit.

3. I carefully cut some new holes for the wiring to pass through.

4. I wired the three sensors in the same chamber together and ran a (shielded) wire along the front edge of the case and over to the volume pot. Then I ran the last sensor out of its chamber to the volume pot, too. I then used shielded cable to connect the volume pot to the jack. 

5. Before putting the guts back in I made sure to seal any extra holes I'd cut in the soundbox chambers and taped the wiring flat against the inside-back so that it wouldn't come-up and hit the reeds or flail around inside.