Acoustic Piano MIDI controller device (Moog/Buchla PianoBar) - Page 1
Forum section: electronics / projects

author: cjt3007
author_rank: Newbie
timestamp: April 28, 2020, 07:14:03 am
content: Hello all, I am looking for some help with a project. I don't have much background in the field of electronics making, but I recently stumbled upon this device that does not appear to be manufactured any longer. It's the Moog PianoBar (which was possibly actually made by Buchla). I came across this device while watching a TEDxCERN videohttps://youtu.be/7oeEQhOmGpg?t=674of Imogen Heap (in which she also modifies the sound with her awesome MI.MU gloves). The PianoBar appears to use some sort of proximity sensor array to detect which individual keys are depressed (and possibly the velocity) on the keyboard. Doing some research shows that there is an accessory that also detects which of the piano pedals are depressed as well.I was considering trying my hand at Arduino programming to make my own version. Would this be the best approach? Any guidance on this project would be super helpful, and greatly appreciated!

author: MarkF
author_rank: Super Contributor
timestamp: April 28, 2020, 05:16:39 pm
content: All the data you mentioned is available through the MIDI port of an electronic keyboard.- Key Down- Key Up- Key Velocity- Pedal Down- Pedal UpRead up on MIDI data.Here is a screen shot of a Sequencer I wrote where I take the MIDI Out from a keyboard andmap it back to the MIDI In of the keyboard creating up to four MIDI channels (voices).Each MIDI channel also has Volume, Chorus, Reverb and Modulation.The yellow highlighted keys are the only ones that play on the second channel.Also, MIDI synths also have a special channels for percussion (i.e. drums, etc.) andspecial effects.It is written for Windows and uses Microsoft Direct Music.

author: cjt3007
author_rank: Newbie
timestamp: April 28, 2020, 07:05:33 pm
content: Yes, that is correct. My goal is to do the same thing with a real acoustic piano, which is why I am interested in creating my own version of the device.

author: MarkF
author_rank: Super Contributor
timestamp: April 28, 2020, 07:47:45 pm
content: TouchKeys: The ultimate!https://www.midi.org/articles-old/touchkeys-expressive-multi-touch-sensing-on-the-piano-keyboard

author: cjt3007
author_rank: Newbie
timestamp: April 28, 2020, 08:05:24 pm
content: Hmm, perhaps I should add more detail to my post? The goal is to do this with an acoustic piano, not a keyboard. Ideally without modifying anything about the mechanics of the piano, and to have the device removable so I can put it on ANY piano - just like the Moog PianoBar. Which is why I’m thinking an array of proximity sensors aligned with each key of the keyboard is the best solution. Using any sensor I’d have to place inside the piano could affect the mechanisms - which is not ideal.

author: MarkF
author_rank: Super Contributor
timestamp: April 28, 2020, 08:23:36 pm
content: By adding some sensor to a regular piano, you will only be ableto add additional sounds when the piano is played.You will not be able to effect the piano sound itself.It will be like playing a duet with a second instrument.You will not be able to play the second instrument by itself with the piano.Is this what you are trying to do?

author: MarkF
author_rank: Super Contributor
timestamp: April 28, 2020, 08:53:12 pm
content: Sensing the keys will be fun.You might be able to arrange an array of switches in front of the keysto sense each key depression. Adjustment might be a nightmare.However, you would need some kind of plunger with two switches to sense velocity.The velocity would be determined by the time between to two switch contacts.

author: MarkF
author_rank: Super Contributor
timestamp: April 28, 2020, 09:15:27 pm
content: I found a disassembled view of Moog Piano Bar showing optical sensors, and diagram of sensor operation.It only gives an ON/OFF state. No velocity that I see.

author: arjen
author_rank: Contributor
timestamp: February 03, 2024, 04:47:06 pm
content: Hey there! It sounds like a cool project you've got in mind. Arduino is a great choice for DIY projects like this. You can definitely replicate the functionality of the Moog PianoBar with an Arduino and proximity sensors. Check out Arduino forums and tutorials for sensor recommendations and coding help.

author: hneve
author_rank: Regular Contributor
timestamp: February 05, 2024, 03:50:30 pm
content: I tried something like this before, where I wanted to add MIDI to instruments that didn't have it. It wasn't easy at first, but Arduino made it doable because there's so much info online, and people are ready to help.I found this fantastic website full of tips about music software and DIY projects for music stuff. It was beneficial for getting the basics down and figuring out how to proceed with my project. If you're looking for step-by-step guides or fantastic ideas on mixing Arduino with music, you canfind hereexactly what you need.

author: pcprogrammer
author_rank: Super Contributor
timestamp: February 05, 2024, 03:57:44 pm
content: Please pay attention to the fact that this topic is from 2020 and that the one to bring it back alive is new on the forum.

author: John B
author_rank: Frequent Contributor
timestamp: February 06, 2024, 12:55:37 am
content: That's fine. Things change in 4 years.The idea is probably useful in some niche cases, but there's plenty of electric pianos with acoustic feeling actions/hammers/weights on the keys. Then MIDI is already built in.One thing that doesn't get utilised much is polyphonic aftertouch.That would be cool to add to a piano, but would require a ton of pressure sensors that don't interfere with the action.The original idea might work for the woman doing the performances as it looks portable enough to fly with, then you can simply installing on any piano for a performance.

author: SiliconWizard
author_rank: Super Contributor
timestamp: February 06, 2024, 01:23:42 am
content: Quote from: John B on February 06, 2024, 12:55:37 amThere are retrofitting kits to "midify" acoustic pianos, and all I've ever seen are based on optical sensors. That's usually the most reliable and least "invasive" approach.For aftertouch sensing, you may add a pressure sensor below each key - the cheapest approach would be to use resistive pressure sensors. Don't know how they would handle constant "hammering" over time, though.Given the number of keys to handle though, never expect anything "cheap". That's 88 times all sensors needed, plus the electronics to multiplex and read all that. Quite a bit of work.