The electroacoustic bulbul tarang.
Originally published at The Null Device Blog. You can comment here or there.
I finished it.
It took a few weeks, required a few redesigns, and it can probably stand for a few tweaks yet, but it’s up and running and sounds pretty decent.
It was an interesting project for me. I am not known for my woodworking skills, and while I managed to hide most of my mistakes on this thing there are a few sloppy bits I wish I knew how to deal with better. But, for the most part, I’m pretty happy with how it came out.
It’s basically a box. I can build a box. A few things had to be kept in mind, though - I had to be able to remove a panel on the bottom so I could access the pickups and electronics if my solder joints break (they are, in fact the World’s Ugliest Solder Joints) or if I wish to incorporate different pickups or a tone control or something. The bottom end of the box needed to be indented slightly so I could make a design improvement - through-body string anchoring allowing the use of ball-end strings (allwoing a much wider range of options for stringing). The top end of the box needed to extend beyond the rest of the box so I could affix tuning machines.
I managed to make all those changes, and for simplicity of assembly I just left an open space in the top instead of a cut soundhole.
My first attempt was to try and graft the tuning machines directly to the body. This turned out to not be a good idea, because with at least rthe sympathetic strings, the distance from the body to the string would be increasing as it approached the “headstock”, meaning the strings would probably lift right off the nut. Not what I wanted. The was fix to shave off the upper corners and make the headstock a bolt-on that attached to the underside of the original “neck”, lowering the tuning peg heads by a half inch. This took a while to accomplish, becasue every time I tried to drill the 3/8″ holes I needed for the tuning machines, the smaller piece of headstock wood would just split and shred from the torque of the drill. I ended up switching to a power screwdriver and a spade bit, which was a slow process but made sure I didn’t tear the wood apart. I also used “compact” tuners, allowing me to pack six of them across the 5.5 inches I had across the top. I can get 8 strings on this thing alrthough right now I’m holding at six because it’s pretty loud (and fussy to tune) at that.
Another design flaw I came across with was the thin metal nut would slide from side to side as the tension of the sympathetic strings changed. This would cause everything to slide out of tune. I tried a friction-based cure- reducing the size of the slot the nut sat in - but that wasn’t enough. Eventually I did a two pronged apprach, putting some posts behind the nut so the sympathetic strings went straight back for a little ways rather than pulling the nut to the side, and putting two small metal staples on either side to physically block any lateral movement.
The original bulbul tarang from which I had cannibalized parts had one flaw that i considered very major - each time you removed or replaced the keyboard mechanism to, say, change the strings, the wood screws holding it on would dig out the holes they were affixed to. After about 5 removals, the screws would no longer anchor into the holes. I installed some connecting bolts and screw-in metal sleeves, and now have a bolt-on keyboard that I can remove without stripping the hole. I had to bore out the post holes a bit in the keyboard, which was a bit dodgy, but it didn’t cause any damage. Another advantage of this arrangement is the keyboard is much more secure and stable that it was on the old one.
Now…the pickups. My first thought was to use piezo, since that’d get the body sound probably better than a magnetic pickup…but my initial tests with a spare transducer I ahd quickly showed that ti was also great at picking up every thump and clack from the wooden keys. Instead, I scavanged a pair of “lipstick”-style pickups from an old guitar I owned. The guitar was shite, but the pickups were nice and warm, and being one big magnet I wouldn’t need to worry about post placement. I had to mount them on blocks first, and adjust (read: bend) the mounting brackets so they were at the right height, and then I screwed everything down to the base of the removable panel. The came wiring. I’d decided that, due to space issues and the fact that I’m lousy with solder, I’d just skip the volume and tone controls or a pickup switch. I’m not expecting to get all Tom Morello with this thing and do weird tricks with shorted switches. Nope, I’m going simple. Two pickups, wired in parallel, straight to the output jack. It…well, it didn’t work so well at first. I couldn’t figure out why my signal stright was so low and so phasey. The it occurred to me to rip off the wires, scrape the solder off the output jack and figure out which post was which and…sure enough, I had the polarity wrong. A frustrating few more minutes with the soldering iron, et voila. It gets a surprisingly acoustic tone with a little ‘verb.
I intend to replace some of the keyfrets and springs, since a few of them have nicks and dents that cause weird buzzes and intonation issues. Also, since the weight of 8 tuning machines and a bolt-on headstock makes the thing a bit topheavy, I had to put a strap on it.
Currently I’ve got it strung with 6 guitar strings of varying gauges, from a few sets of “extra thin” strings. I bought a 3-pack of the strings for a whopping $10, which is cheaper than a pack of “official” bulbul tarang strings, and seems easier to find. Also, frankly, I think they sound a lot better. Just those six make a much brighter and louder sound than the full complement of 10 thin strings. Something to keep in mind, I guess.
I also need to learn how to play it properly. Heh.