HOW TO BUILD?

[YAYBAHAR No.865134]

Ive wanted to build one for a while but now im tired of waiting for magical plans to appear. The main unknowns are how the springs attach to the drums and also to the strings.

Looks like:
>two springs ~1/2"d 4' long (possibly one long spring from drum to drum?)
>2 different sized drums
>metal frame ~steel angle should be fine
>2? strings ~cello or bass + tuning hardware/knut
>fretboard of some sort could be just a piece of pipe, hard to tell
>bridge? would it even need one? again hard to see it
>bow

I would make an L angle steel frame, easily broken down for transport. Craigslist a wrecked instrument with a good fretboard. I would go ahead and make a bridge system although that makes breakdown and transport more difficult. The drum to spring connection is troubling,not sure if just threading the spring through a hole in the drum and epoxying it would hold. it seems like it would transfer vibration well. maybe a metal hook attatchment could be rigged to the drum centers. Would just putting hooks of the bottom ofthe bridge be enough to transfer well? Looks like it could be done for under 150, just hard to know what to do and will probably need tweaking springs, drum material? etc

youtube.com/watch?v=j_LW-eUYt7Y

[Anonymous No.865154]

>>865134
This looks pretty interesting, please post another thread with pictures if you progress on it. Can't give any feedback or advice, since I'm just lurking DIY.

[kg No.865372]

>>865134
> OP wants to repro a 1-off art instrument

OK, I'll bite. Couple of comments.

You don't need to tear apart a stringed instrument for this. Look up cigar box guitars. The "neck" on this instrument is basically the neck/body from one of those. If you can't make one of those from a 1x3 and a couple tuners, this project is beyond you. There are no frets or fret board... this is a slide instrument (like most CBGs.) Nut and bridge will just be steel rods... really any bolt.

The drumheads would need sourced. I don't know drums but don't expect that will be an issue. I'd mimic the proportions he used (get a dimension estimate on each head and duplicate.) I think the size diff between heads is the key here... I'm betting that they're tuned acoustically to either octave or one is the 5th note of the other. to produce a good chordal tone.

The attachment to drumhead "face" (or whatever you call it) could be just a flat coin with a loop attached. Either hot glue or epoxy would be sufficient for this connection. I'd try the hot glue first, as you can remove it when needed with rubbing alcohol (epoxy will be permanent).

[kg No.865379]

>>865134
>>865372
Watched a couple videos of him playing this thing again to see what else I could add.

You're right, it does have frets. I'd still go the CBG route and just pound fret wire into the 1x3 in the proper pattern. Or make it fretless and play it as a slide instrument. Fretless is what I'd do to start; it would be easy to replace later.

It appears what he's done is connected the bass and treble strings via spring independently to the large and small drum head, respectively. The connection of spring to string will be important... I think you pull a bit of the spring straight, wind it around the acoustic string tightly, and use nocks (like you would on a bow string for bow and arrow) to keep it positioned on the string at a set distance from the bridge. This distance will be a variable you'll need to experiment with. You'll need a similar connection to drumhead face mount (pull string straight, tightly coil around loop.)

The other variable is the long spring... not sure where you source that, but the spring coefficient (K) and it's static tension will both be variables that will change your sound. For starters, I'd just try to find any light, long spring you find, and tension it enough to keep it from slacking into the frame. Then, play with tension until you get the right sound. If still not right, start looking for springs with higher / lower K. They remind me of reverb springs, which is exactly what their function is here.

The frame design is trivial. Looks like wood. I'd use that.

At the end of the day, it's a 2 string guitar with mechanical amplification (vs electric), made more complex with the addition of reverb springs (vs. rods).

LMK if Qs and I'll see what I can add.

[Anonymous No.865407]

>>865134
I'd like to add that when I first saw this instrument a while back, I was reading up on it and seem to recall that the membranes (drums) were suspended between 2 toruses, not just a steel loop.

[op No.865412]

thanks for the input. i am a classically trained bassist so i would like to scavenge/build a proper fingerboard bridge setup, and build in the option for additional strings. alsono frets for me, but itd be nice to have that step down mechanism on the low string, would be E to D on bass, could even extend it to C which is called an extension on a real instrument.

you are right, the frame could be wood. in a normal stringed instrument, the strings vibrate a bridge which in turn vibrates the front panel, finally amplified by the rest of the body. in this thing it goes string, bridge, spring, amplified by the drums. somehow the springs must have tight contact with the bridge, or for that matter variable contact which would allow for volume control.

nice spot on the independent drum/strings. so i would need to plan for more drums as well as strings. also itd be cool to have above system so string volume becomes independent.

[kg No.865469]

>>865412
Assume by classical bassist you mean upright bass. I play electric bass as my main instrument.

You won't be able to just salvage a bolt-on bass neck. You'd also need the body potion (part of it, anyway) to set the saddle to right distance. Even fretless you'll need it to set scale length. Either way this part of this instrument would be easy to change. I'd build neck like a CBG at first, with electric bass scale length, tuners, and strings. If you haven't seen build details, google them. The neck on original instrument looks identical; I've built several in past.

A drop D tuner on this would just mean building neck/body with one, as well as using electric bass scale length and low E string... to keep things simple and predictable. I think, though, that trying to play this instrument to a classical level of accuracy may be missing the whole point.

> in this thing it goes string, bridge, spring, amplified by the drums. somehow the springs must have tight contact with the bridge,

You mention bridge pickup again... to be clear, this instrument is not resonating like a violin / acoustic guitar, where the bridge drives vibration to the soundboard to create noise. You should be thinking of this like an electric guitar, where the bridge (arguably) does nothing aside from setting string length, and the electrical pickup takes the sound to an electric amp.

In the "yaybahar," the pickup is the connection of individual spring to string. Sticking with the analogy, the patch cord and reverb pedal are the spring. The amplification is the drum head.

So, it's string -> spring -> drumhead. The bridge plays no part. For a bridge pickup to work, you'd need a soundboard that moved under the bridge. This instrument has none. Nor would I re-design this instrument to have one.

Agree that if you run multiple strings you would need multiple drumheads.

[Anonymous No.867181]

>>865134
So OP, whatcha going to do?

[Anonymous No.867181,1]

There is a Facebook page for the instrument with some photos. There is only one so far with any real detail for how the spring is connected the fret board.

It looks like the bridge is UNDER a hose clamp which is holding the fret-board to the frame/stand. The detail of how the spring is linked is not real clear though....