Thanks! My other brilliant idea was frets made of glass--no wear, perhaps interesting harmonic qualities! Since I thought of that, I have been introduced to the concept of "fret leveling" and realized the problem making them of glass would create.
Enjoy the benefits of a premium membership!
Upgrade Account
-
TalkBass has been independent since 1998. Add your voice.
Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
Join free Log in
Want zero display ads or expanded classifieds tools? Compare plans.
Idea: Harmonics from Four Solid Aluminum Rods used as Electric Upright Bass
- Thread starter Mustafa Umut Sa
- Start date
Thanks! My other brilliant idea was frets made of glass--no wear, perhaps interesting harmonic qualities! Since I thought of that, I have been introduced to the concept of "fret leveling" and realized the problem making them of glass would create.
Thanks! My other brilliant idea was frets made of glass--no wear, perhaps interesting harmonic qualities! Since I thought of that, I have been introduced to the concept of "fret leveling" and realized the problem making them of glass would create.
Thanks! My other brilliant idea was frets made of glass--no wear, perhaps interesting harmonic qualities! Since I thought of that, I have been introduced to the concept of "fret leveling" and realized the problem making them of glass would create.
Invalid Link Removed
This guy plays fretless guitar with a glass board. A little different from glass frets. He said they tried a bass like that but roundwounds tear up the glass. Met him a couple of times when I lived in Idaho. Real nice guy.
Sorry for the derail(s). Back to the OP. You're asking if you can accomplish a specific technique on an instrument that doesn't exist so I don't know that you will get any real world answers. I would be interested to read about it if you do build something. The silicone tubes seem thought provoking. I know Guild and DeArmond used silicone strings on the Ashbury basses. You're a bit out of what I can imagine as far as pressurizing them to tune them, however. Keep us posted.
Solid rods like you describe can be made to vibrate, but they are most resonant with compressive vibrations - hold the rod loosely at about a fourth of its length, and strike it on the end - it'll ring like a bell. Glue a thin disc of steel on the other end, and put that over a magnetic pickup. Only problem is, to get 4 notes, you'll need 4 different length rods. For bass notes, you'll need really long rods.
If you try to use rods like that with the movement being sideways (like a stringed instrument), you'll learn really fast why strings are wound, not solid. Solid rods have a lot of inherent stiffness - in flex, they're a dispersive medium, and the velocity of propagation is not constant with frequency. Practically speaking, that means the overtones of the vibration are not harmonics of the fundamental - the thing will sound out of tune with itself.
If you try to use rods like that with the movement being sideways (like a stringed instrument), you'll learn really fast why strings are wound, not solid. Solid rods have a lot of inherent stiffness - in flex, they're a dispersive medium, and the velocity of propagation is not constant with frequency. Practically speaking, that means the overtones of the vibration are not harmonics of the fundamental - the thing will sound out of tune with itself.
I didn't know this about marimbas. Makes sense, I think...
I have seen cymbals, vibraphones, and large chimes bowed (with a doublebass bow). I don't know if some combination of that (or some variation on the mallet idea) and touching the rods at certain points along their vibrating length might yield the overtones you're after or not (practically -- or even theoretically -- speaking).
As rich Snyder said, I would try with one rod first -- and, then, I might try a miniature (one or two octaves up) version to test your concept before moving on to a larger and potentially more difficult and expensive build. Re. pitch, I wonder if increasing the diameter of a hollow rod (along with varying the wall thickness/material/average mass) would affect the pitch in a way that would let you get what you want without having the rods be prohibitively long.
I would do some research on instruments that might operate on a similar principal and/or consult a physics forum as well... this might be a fun project for the right type of egghead(s)!
(We might even have some here!)
There've been a lot of good suggestions in this thread. I would add that you should consider materials. Aluminum is more rigid than steel (for tubes of similar diameter and wall thickness) and will sound damped compared to steel. You might also want to investigate how brass and iron might work for your needs.
Someone might make a guess as to the weight of this in aluminum, steel, iron, or a composite metal. I'm thinking iron would be too heavy to move around.
Sounds like a big Kalimba, no reason why it wouldn't work with a piezo pickup.
Probably worth looking at how these are made:
Probably worth looking at how these are made:
This would be classified as a metalliphone, an instrument where rigid materials produce the sound. Like marimbas, vibes, xylophones. They vibrate in completely different ways than cordophones - stringed instruments.
The only way mettaliphones make music is by being struck with a mallet or hammer.
The only way mettaliphones make music is by being struck with a mallet or hammer.
Really interesting physics problem. The distribution of harmonics on a vibrating string are caused by the boundary conditions, specifically that the string is fixed at both ends. The longitudinal waves reflect perfectly at the ends, the interference of all of this reflections produces the harmonic series. So if the rods are only supported/fixed on one end, they would resonate more like a tuning fork. You could probably look up the harmonic series and nodes/antinodes for a tuning fork, I would be surprised if that problem has not been solved.
Ha. The solution to a 21st century glass "finger surface" (it ain't a board by traditional definition) that can't take the abrasivness of modern strings, would be a mid 20th century product.....flatwounds....
Yeah, I had the same thought as waltsdog. Basically a giant kalimba.
I would expect that you should be able to hit it with a mallet/piano hammer/etc... while putting pressure on a node and get some harmonics going.
The key though to the whole enterprise would be to figure out the right dimensions for the rods so that they would work as intended.
But why stop at 4 notes? If you did EADG that would be severely limiting musically, even with harmonics. A chromatic octave would be a lot more flexible, or at least a full 7 note diatonic scale. I think absolute least you could get away with would be a pentatonic scale. At least if you wanted to get an actual musical instrument out of it.
I would expect that you should be able to hit it with a mallet/piano hammer/etc... while putting pressure on a node and get some harmonics going.
The key though to the whole enterprise would be to figure out the right dimensions for the rods so that they would work as intended.
But why stop at 4 notes? If you did EADG that would be severely limiting musically, even with harmonics. A chromatic octave would be a lot more flexible, or at least a full 7 note diatonic scale. I think absolute least you could get away with would be a pentatonic scale. At least if you wanted to get an actual musical instrument out of it.
7 note diatonic scale would be excellent , it would be like an harmonica.
Let me ask , if I hold heavy steel cube and touch the rods , would it be act like an fret ? One friend suggested ring but controlling 7 ring or 4 of them would be very difficult. I think after that , this would not be my invention. One german guy made strange wood pieces and bow them additionally with heavy piece of metal fret. I think I am the first suggesting play with fingers like an bass or EUB.
I think assembling 4 or 7 rods could be easy but cutting plywood with 6 or 3 slots at laser cutter is even more easier.
I thought slotting giant triangle lenghtwise of a 10 cms or 4 inches to 45 inches -110 cms rectangular is a other idea. These 3 triangles can make sounds different at each finger tip.
What do you think ?
Let me ask , if I hold heavy steel cube and touch the rods , would it be act like an fret ? One friend suggested ring but controlling 7 ring or 4 of them would be very difficult. I think after that , this would not be my invention. One german guy made strange wood pieces and bow them additionally with heavy piece of metal fret. I think I am the first suggesting play with fingers like an bass or EUB.
I think assembling 4 or 7 rods could be easy but cutting plywood with 6 or 3 slots at laser cutter is even more easier.
I thought slotting giant triangle lenghtwise of a 10 cms or 4 inches to 45 inches -110 cms rectangular is a other idea. These 3 triangles can make sounds different at each finger tip.
What do you think ?
D
Deleted member 165050
Guest
Then how can you are going to get the right tension at start, with no tuning system ?
Aluminum is less stiff than steel. However, it's density is far lower, so typically it'll resinate at a higher frequency in the same geometry due to the ratio of stiffness to mass being higher.
Aluminum does have more damping than steel, but a hardened piece if aluminum still has very low damping - it'll ring just fine if suspended the right way.
Hmm, do a search online for Harry Partch. He thought along similar lines when it comes to inventing non-conventional instruments. 1950s I believe.
