Door harp - advice sought!

Hi. I saw these in Japan last year, and I would like to make one:
Attachment 378137

Apparently they're called "door harps" and when a door is opened, the hammers bounce against the wires to make notes. I'f found some examples on the internet, even plans, but nothing really discussing how to improve the sound quality.

I was wondering if anyone had some advice on how to make them sound decent - I'm not trying to get carried away - its not a guitar - but just wondering what the key elements were. Suggested materials? Size of cavity? Thickness of walls? Any thoughts appreciated.

I have one of the door harps, bought it decades ago. Mine is a flat piece of wood and the wooden balls are suspended with very fine fishing line. There isn't a hollow area in the base like your picture but they definately make plenty of sound. When the balls are suspended with fishing line they tend to strike the stings at different places when they bounce, just enough to change the tone a wee bit.

Ours was pretty cool at first then we got real tired of the noise and put t in storage :)

I've never made one but I might use piano tuning pegs for tuning (especially since I have some on hand from a player piano rebuild). I'd probably get pretty tired of it if the strings were not tuned to some chord. (we have a wonderful wind chime tuned to the key of G and I find it pleasant) Piano tuning pegs are threaded with very fine "threads" but they are hammered into holes in a laminated hardwood block then turned to tune. You might also look for tuning pegs made for instruments like a psaltery. http://www.apsimplepsaltery.com/ (BTW, this is by the guy who runs the Wood Database!!, my most used wood info resource: http://www.wood-database.com/ )

As for the construction, unless the door is heavy, solid, or filled with some kind of insulation it might resonate enough for a good sound. I demonstrate a tuning fork by holding it against an interior door. That, or a music box movement held against the candidate door should let you know if the door will act like a sounding board or if you need a cavity with a sounding board front.

JKJ