Sorry to upvote a pedantic comment, but the instrument here is definitely not a wood or kelon xylophone, and is instead a glockenspiel. The solenoid striking scheme would probably need to be slightly different for a xylophone, to avoid wear on the more delicate keys. A softer, rounded tip, needing more clearance beneath, would probably be required. Marimbas and vibraphones would require even softer strikes as well. Really great project!
They're about $1-2 apiece on Aliexpress; I doubt making your own can cost much less?
In my experience, making one solenoid is fun just to see how it works (and how simple it is, really); but making more than one is a little painful and not fun.
> to learn a bit more about electromagnetism, so making your own solenoids is not even a bad idea
You can learn by making one. Making 24 is super annoying IMHO.
(Also, if you want to try, ready-made sewing machine bobbins are a good alternative to 3D-printing your own solenoid body.)
And about the rest of your comment: one approach would be to buy one solenoid from Amazon, to let you do experiments and set up the whole machine, while waiting for the rest of the goods to arrive from China.
I'm used to my online purchases taking time. The closest thing we have to Amazon is Ozon, it's 1-2 days if you buy something that's already in a warehouse in your city (i.e. if you're lucky) and several more days if it's not.
I pretty much always buy components from either Amazon or eBay. Is that unusual?
I just looked on Farnell and the cheapest solenoids that I could find in stock have a weird housing (and they're £6.38 each which is already more than Amazon), the cheapest sensible ones that are in stock are £12 each, which is way more expensive than Amazon, plus you have to pay VAT and postage on top, plus you have to faff around with their enterprisey order form, compared to one or two clicks on Amazon.
Yes, it's unusual for professionals, just fine for hobbiests.
Because of reliability, etc.
For the same reason you wouldn't order your ingredients for a professional Michelin starred restaurant from Amazon.
I've almost never found Amazon cheaper either. The sellers on Amazon are almost always not the original manufacturer, they're usually FOB folks who are just buying big boxes of things and then selling them individually.
You're almost always better served to swim upstream and get things from the manufacturer, or from reputable electronics distributors like digikey, Farnell, mouser, jameco,etc. A quick search at some of those and I'm finding suitable solenoids at $2-5
It's not that Digikey or mouser is taking those inexpensive overseas solenoids and marking them up.
The products on mouser and digikey are from reputable industrial component manufacturers. They have warranties and datasheets, support from the mfg, traceability and trustability, etc.
They're simply different products. You can't compare a quality made product from a quality supplier and manufacturer to cheap crap you buy on amazon
It's both. The product on Digikey is quantifiably better in many regards. It's also got a price premium on top of the increased price from the OEM. You have to pay Digikey enough to make it worth their while to ship 1 of something to you.
Pat Metheny made an album called Orchestrion using an entire orchestra/band of real instruments played by solenoids over MIDI. Great music. (If you like Pat Metheny.)
It was an insane project. He even took it on tour.
Although I missed seeing the Orchestrion tour in the 2010s, Pat still takes a subset of these instruments on tour with him. Both of his two previous tours, Side Eye and Dream Box had parts of the concert that had robotic percussion and wind instruments.
I have a full octave of organ pipes, and I've always dreamed of making an instrument out of it. I've just never figured out how to make the electrically-actuated valves.
As for electronic control, it shouldn't be too hard - perhaps you already know the following, but I'll write it here in case it's useful. You'll need as many electromagnetic solenoids as you have pipes. First you need to construct a 'wind chest', which is a shallow, air-tight box that can be made of any material. A plastic storage tub should do fine. Then you punch a hole in the top of the wind chest for each pipe, and make some sort of grommet to hold the pipes in place in the holes; this would be a 'toe board' on a real pipe organ. Mount the solenoids directly under the holes, and attach something soft to squish up against the pipe and stop the airflow. You of course need to have a blower that can pressurise the wind chest.
No guarantees about how that's going to sound! :) If you wanted to construct something really high-quality, you could follow Raphi Giangiulio, who has documented every stage of his fully-mechanical tracker organ: http://www.rwgiangiulio.com/index.htm
The artist is Grandbrothers and one of them is a jazz pianist and the other one is a roboticist. The latter sets up systems to control solenoids striking the strings and body of a grand piano while the former plays on the keys. It's a duet between human and machine.
Daisy and Bela are great for low-latency interactive audio :)
But I think Arduino is a good choice for this.
1. The microcontroller isn't generating audio onboard, it's driving solenoids to hit something. Arduino can do that — the solenoids have travel time but Bela wouldn't solve that.
2. This is more like a sequence playback machine, there's no continuous real-time interactivity. Play/pause is the main interaction and a few ms is ok.
(If you wanted to duet with it latency-free the top of the xylophone is completely exposed so you can just play it normally.)
Cool device. The electronics for "continuous note shaping" would be a lot more complicated than just 'hitting' a note, which could be as simple as a single pull and release (probably not very loud without a much stronger electromagnet).
You could send a plain sine wave matching the frequency of the bar above it, but at that point you've just invented a single frequency speaker.