10 ms·
Show HN: Haxophone
I built this during Covid. When I released it, some of the parts went out of stock or skyrocketed in price, no longer making this an economic DIY project. Now that things are getting back to almost normal, I thought I'd share it here and request feedback. This is a very niche project for people who like the same things I do: saxophones, Rust, mechanical keyboards and the Raspberry Pi.
- tomcam 4y ago> This is a very niche project rockets to #1 on Hacker News
- amelius 4y agoSince it's using keyboard keys I'm guessing it doesn't have any analog touch sensitivity (?) Not sure if that would be even needed on this type of instrument though.
- zwkrt 4y agoFrom what I understand of playing a saxophone the variability would come from the mouthpiece. On a type of instrument like a saxophone the valves should always be cleanly opened or closed.
- jefftk 4y agoHalf fingering is a thing, but very rare and fine to be out of scope for a project like this
- insane_dreamer 4y agoIt seems the keyboard is pressure sensitive (reference to a pressure sensor in the HW section)
- seniorsassycat 4y agoPressure sensor is in the mouth piece. I've always thought saxophone keys were on or off
- javier_cardona 4y agoActually the pressure sensor is on the PCB. Pressure is transferred from the mouthpiece through a flexible silicon pipe. You can see the details in the assembly instructions here: https://github.com/jcard0na/haxo-hw/blob/main/docs/assembly.md#6-solder-pressure-sensor https://github.com/jcard0na/haxo-hw/blob/main/docs/assembly....
- javier_cardona 4y agoYes, there is no analog touch sensitivity on the sax: keys are either open or closed. The pressure sensor is for volume and note attack.
- junon 4y agoThere exist analog keyswitches, have you considered playing with those?
- mkl 4y agoI'm really interested in this idea for other DIY instrument purposes. Razer has keyboards with optical ones, and some people have made them by putting inductive sensors underneath mechanical switches, but I couldn't find any analog keyswitches for sale. Do you have some examples? How can you deal with a large number of analog inputs to a Raspberry Pi or similar?
- junon 4y agoI don't remember how many analog input pins exist but a separate circuit that digitizes many analog inputs to a serial stream would be how I'd do it, personally.
- jcard0na 4y agoWhile it would be interesting to play with analog keyswitches, it would depart from the experience of a real sax, where the "half pressed" key is of not much use. And it would dramatically increase the complexity of the design. But the full design is published, just in case anyone wants to try :)
- jedimastert 4y agoThis is also true of the EWI, all of the keys are just metal plates that detect contact, and also generally true of saxophones (although very much not the case with clarinets, which have open finger holes)
- code_runner 4y agoAs the owner of a (recently revived) ewi-usb… I’m really curious about the mouthpiece bit. What kind of analog sounds are happening while playing this? Do you notice that reed age, strength etc are as impactful as on a real saxophone? Do you feel a need to swap mouthpieces for different styles of playing? I love the idea and ingenuity to make this happen!
- bwanab 4y agoAs a sax player who also plays a Roland Aerophone, I have a similar question. Is the mouthpiece a real sax mouthpiece and reed? If so, that means it's making a lot of noise. One of the main appeals of windsynths is that I can play at times when the people in my household (and neighborhood) don't really want to listen to it. That said, it's a cool project.
- javier_cardona 4y agoThe sounds are synthed sounds (I used fluidsynth) and the haxophone just uses the sound pressure to infer velocity of the notes. The mouthpiece is optional: you can blow on the neck of the device and will get the exact same sound. But as a sax player, I really prefer to use it with a mouthpiece blowing through it but without making the reed vibrate (so no sound). I find that it helps me maintain proper embouchure and feels more comfortable. And after a solid practice session, I still get that gratifying tingling lower lip feeling. Thanks for the feedback! https://github.com/jcard0na/haxo-hw/blob/main/docs/assembly.md#15-optionally-attach-a-mouthpiece-with-reed https://github.com/jcard0na/haxo-hw/blob/main/docs/assembly....
- code_runner 4y agoVery cool! Awesome project
- tgv 4y agoThe design says that it measures air pressure. So it's just blowing into a tube, much like e.g. the Yamaha BC-1. I've got one, and in the demo video, I hear the same rapid changes in volume/pressure. I would guess it could benefit from having a small, adjustable opening (like the BC-1), which makes it a bit easier to control.
- klaff 4y agoAre there sound samples anywhere?
- simlevesque 4y agoThe video in the repo's readme shows a solo from Stevie Wonder's "Isn't She Lovely"
- seniorsassycat 4y agoThere are some really cool wind synths out there https://m.youtube.com/@EddieEWI https://m.youtube.com/@EddieEWI
- squarefoot 4y agoYou can overcome the RPi scarcity by migrating the code to the Teensy platform, which aside being cheaper and less power hungry than the 2,3,4 RPi, is a lot cheaper and more easily available. Not an easy task since there's no Linux under the hood, but there are some excellent audio/midi libraries to help. They already built commercial-level synthesizers with it. By combining the breath sensor data with other pressure sensors you could end up with a very expressive instrument. https://www.pjrc.com/teensy/index.html https://www.pjrc.com/teensy/index.html https://www.pjrc.com/teensy/td_libs_Audio.html https://www.pjrc.com/teensy/td_libs_Audio.html https://www.pjrc.com/teensy/td_libs_MIDI.html https://www.pjrc.com/teensy/td_libs_MIDI.html https://www.youtube.com/watch?v=z2674LdYW5I https://www.youtube.com/watch?v=z2674LdYW5I
- ruleforty 4y agoBefore I’d do any of that would be vibrato. Without it it is a emotionless keyboard with a blowtube.
- postalrat 4y agoI don't know. Looks kinda easy to do vibrato through your blowtube https://www.youtube.com/watch?v=XtsZZKZcNC4 https://www.youtube.com/watch?v=XtsZZKZcNC4
- oriolid 4y agoIt's tremolo, vibrato would be oscillating pitch. Real woodwinds can do both. And yes, Fender got them the wrong way.
- code_runner 4y agoIf I had the knowledge/ability/skills to build an “emotionless keyboard with a blow tube” I’d be pretty damn happy. I don’t think a lack of vibrato diminishes what is going on here. Am open sourced wind synth made with a custom keyboard? Pretty sick IMO
- schappim 4y ago
- mftb 4y agoI'm not exactly in the target audience, but this is brilliant. Bravo!
- pepepep 4y ago
- pepepep 4y ago
- throwaway413 4y agoThis is one of the coolest things I've seen on HN. I am definitely going to try to follow the instructions on this in the near future! I don't even play saxophone, but now I am not definitely going to learn. I would 100% buy one of these, if not 3 so I could give some as gifts. Thanks for sharing and seriously, awesome project. Almost brings a tear to my eye.
- apienx 4y agoSo this is how holophonors came about...
- xavdid 4y agoThis is great! As someone who used to play sax a lot but doesn't have hardware experience, it's 100% the sort of thing I would buy if it were commercially available. Makes sense that it's not (ecommerce is a whole thing), but I don't really have the patience to source all the parts and assemble it. Awesome project though!
- matthewhartmans 4y agoLove this! Well done OP and thanks for sharing the code!
- jader201 4y agoThe video doesn’t seem to load on iPhone (Safari). It loads a tiny thumbnail, then just spins forever. Edit: it may be because I’m opening it from the mobile link (which sends the video to Safari), but I tried pulling up the repo directly in Safari, and it shows a whitespace placeholder for the video but that’s it.
- javier_cardona 4y agoFWIW, I just tried it on iPhone and works for me...
- WickyNilliams 4y agoThis is extremely cool. Surprised how good it sounds in the example video. Wish I knew enough about hardware to build one (OK, i also wish i knew how to play sax). Shame there's nobody shipping all the parts for assembly at home. In any case this is awesome, and one of the cooler things I've seen on HN recently!
- olivermuty 4y agoCan you do a trombone next so we can play trombone hero with a real trombone? :D
- wilsonnb3 4y agoI bet it would be pretty easy to rig up a PBone or PBone Mini to play trombone hero with
- rudolfwinestock 4y agoHere are other innovative electronic instruments. The Eigenharp: https://www.youtube.com/watch?v=9MR5qBtPRrM https://www.youtube.com/watch?v=9MR5qBtPRrM The Artiphon Instrument1: https://artiphon.com/pages/instrument1 https://artiphon.com/pages/instrument1 The Linnstrument: https://www.rogerlinndesign.com/linnstrument https://www.rogerlinndesign.com/linnstrument
- system2 4y agoArtiphon videos don't play on the browser. They chose some weird player with unknown host... Why...
- chuchana 4y agoThe Soundplane: https://madronalabs.com/soundplane https://madronalabs.com/soundplane
- diydsp 4y agoThe Brooklyn Eel: https://youtu.be/huYJa2Du57g https://youtu.be/huYJa2Du57g
- BHSPitMonkey 4y agoThe Commodordion (which also made the HN rounds recently): https://linusakesson.net/commodordion/index.php https://linusakesson.net/commodordion/index.php
- flipcoder 4y agoI own a LinnStrument and it's fantastic. I created a custom note layout for it to make it easier to play: https://github.com/flipcoder/linnstrument-wholetone https://github.com/flipcoder/linnstrument-wholetone. The firmware is also open source. It feels like the Linux of instruments.
- wilsonnb3 4y agoFor those who are more into the “cheap sax like instrument” part rather than the electronic part, you should check out the Yamaha Venova line.
- b20000 4y agoany info on kernel config, drivers, rootfs etc used?
- javier_cardona 4y agoIt's running vanilla Raspberry Pi OS, alsa drivers and fluidsynth, all configured from the main Rust application (https://github.com/jcard0na/haxo-rs/blob/main/src/synth.rs https://github.com/jcard0na/haxo-rs/blob/main/src/synth.rs)
- archarios 4y agoIf you want a really high quality premade thing like this, Johan Berglund is your guy: https://berglundinstruments.mediarif.com/ https://berglundinstruments.mediarif.com/
- mdmglr 4y agoReminds me of the EWI: https://en.wikipedia.org/wiki/EWI_(musical_instrument) https://en.wikipedia.org/wiki/EWI_(musical_instrument). Which several people in my high school band would play in the locker rooms.
- dmead 4y agoI have an akai ewi sitting on my desk
- ninjakeyboard 4y agoMy girlfriend knows how to play the sax and I know rust (and am a dj/producer!) - so I starred this and we plan to build it. Thanks for your contribution to our life!
- beau_g 4y agoGreat work, I am going to fork this into a digital didgeridoo project, or digeridoo for short
- deleted 4y ago[deleted]
- slmjkdbtl 4y agoThis is so cool! Interesting you can use normal mouthpieces. Curious how the sound works, does the reed need to vibrate like a real saxophone, or you just need to blow into it and some air pressure sensor picks up (forgive me I have no hardware knowledge)?
- javier_cardona 4y agoNo the reed does not vibrate. It's there to restrict the airflow and to provide a similar embouchure to a real sax. Some more details here: https://github.com/jcard0na/haxo-hw/blob/main/docs/assembly.md#15-optionally-attach-a-mouthpiece-with-reed https://github.com/jcard0na/haxo-hw/blob/main/docs/assembly....
- pom34 4y agoI had the chance of making one in Oct 2021 following Javier's advices on his docs. This was a lot of fun. I printed the 3 required parts on my Prusa MK3S 3D printer. Perfect at the first attempt. I learned how to weld, not so difficult and I could make it also at first attempt. The MPXV7007DP component was indeed difficult to find at that time, but I could find one at Farnell for 18€ (and Digi-Key at 19€). It seems it's still difficult and expensive to find at the moment (but available at about 25€). The result is very nice. The sound also very good with most of the effects you can have on a real sax. And I love the geek look of this sax.
- poulpy123 4y agoSomewhat related, this guy is making a lot of cool instruments that looks reasonably easy to build https://www.youtube.com/c/NicolasBras https://www.youtube.com/c/NicolasBras