MIDI concertina project

[Don Taylor]

10 minutes ago, Paul_Hardy said:

Certainly the Hall effect contactless switching mechanism used by Roy of Accordion Magic has worked well - no dirty contact problems.

 

I concluded that using Hall effect sensors is the only way to go, which implies making something like a regular action mechanism.  Then I think that you need  set of real (good quality) bellows along with some pressure sensors to give you the abiilty to shape the sound and suddenly you are more than halfway to building a real concertina.

 

Wim Wakker once sold a midi Anglo with real bellows and electromechanical switches.  I believe that the lifetime of the switches was very short and Wim no longer sells that concertina.  It is a pity that he did not use one of his action boards along with Hall effect sensors.

[Richard Mellish]

On 3/21/2019 at 10:01 PM, Don Taylor said:

I concluded that using Hall effect sensors is the only way to go, which implies making something like a regular action mechanism.  Then I think that you need  set of real (good quality) bellows along with some pressure sensors to give you the abiilty to shape the sound and suddenly you are more than halfway to building a real concertina.

 

Wim Wakker once sold a midi Anglo with real bellows and electromechanical switches.  I believe that the lifetime of the switches was very short and Wim no longer sells that concertina.  It is a pity that he did not use one of his action boards along with Hall effect sensors.

Why are mechanical switches troublesome in this application? They work well enough in computer keyboards. And for a MIDI concertina you don't need them to be velocity sensitive as you do on a piano-style keyboard.

[Don Taylor]

2 hours ago, Richard Mellish said:

Why are mechanical switches troublesome in this application? They work well enough in computer keyboards. And for a MIDI concertina you don't need them to be velocity sensitive as you do on a piano-style keyboard.

Computer keyboard switches were the only electromechanical switches I could find that would be durable enough.  The switches  made by Cherry specifically for gamers (who make their own custom keyboards) were by far the best and one of them, the Cherry MX Red I think it was, needs 50gm force to close and does not have a tactile click - perfect  This looks ideal but, like all computer keyboard switches, it has a large footprint.  Anglo players might just about accept the larger spacing (I don't know that for sure) but I wanted to build a Hayden and they simply would not fit together that would yield anything close to the inter-button spacing.  An EC would be the same or even worse.

 

If l wanted to build a melodeon then these Cherry switches would be my first choice.  

[Devils' Dream]

Having a Streb provides insight to a lot of your comments here.  Cannot imagine not having the bellows and bellows/attack expression controls.  The Lachenel patch is pretty nice.

Edited March 24, 2019 by Devils' Dream
clarity

[Bill N]

I've been lurking on this thread (although do not pretend to understand most of the technical info), as I have always been interested in the possibilities of such an instrument- especially the "silent practice" function, and the ability to change the key one is playing in with the press of a button.  I saw a respected player of traditional Newfoundland dance music playing a digital button accordion last summer (a Roland as I recall), and in all respects it seemed like a very successful and fully sorted instrument.  I wondered why this technology hasn't made its way to concertinas?

[SteveS]

4 hours ago, Bill N said:

I wondered why this technology hasn't made its way to concertinas?

Probably because it's not economically viable.

[Richard Mellish]

On 3/24/2019 at 4:54 PM, Bill N said:

 I wondered why this technology hasn't made its way to concertinas?

 

On 3/24/2019 at 9:14 PM, SteveS said:

Probably because it's not economically viable.

I would like to explore that. How would the prices compare for, say,

a) a normal 30-button anglo

b) the same 30-button anglo but with switches instead of reeds

c) a MIDI keyboard laid out like a 30-button anglo but without bellows, levers, pads etc, just a strain gauge (or if necessary two or three) to monitor the direction and strength of the force applied by the player?

[SteveS]

2 hours ago, Richard Mellish said:

 

I would like to explore that. How would the prices compare for, say,

a) a normal 30-button anglo

b) the same 30-button anglo but with switches instead of reeds

c) a MIDI keyboard laid out like a 30-button anglo but without bellows, levers, pads etc, just a strain gauge (or if necessary two or three) to monitor the direction and strength of the force applied by the player?

It's not just the building of an instrument - a considerable amount of time and money must be spent on the R&D, prototyping, productization, and whole host of other things that must be done before a product can be ready for deployment in the wild.  These elements are just not economically viable given the likely very small user uptake of any instruments. 

Edited March 26, 2019 by SteveS

[Devils' Dream]

SS:  Needs to be a labor of love, I guess.  Steve Rouses Strebs are reasonably priced similar to a  nice "real" melodeon of similar construction.  But then he has over the years amortized the R&D/proto/production into what is now the finished product.  They are "small user uptake" as you say, but he has a wait list and used ones sell in one day...  And the software is cool.  Besides being able to change to any key, you can customize the buttons, the voices, etc. etc.  Want to try an F#'' drone?  Oops, make that an A#', no prob.  Play concertina on one side and bass viol on the other? No prob.  Economically, tho, the Roland FR18 should have been a hit, but wasn't, so maybe you are right...

[alex_holden]

I have an electronics background and spent some time thinking about electronic concertinas before going down the traditional reed route instead. The biggest thing that puts me off developing any kind of low-volume electronics product is the cost of EMC compliance testing. It can easily add thousands to the R&D budget, especially if you want to sell it internationally. Obviously not an issue if you're a hobbyist building a one-off for your own use.

[SteveS]

45 minutes ago, Devils' Dream said:

Steve Rouses Strebs are reasonably priced similar to a  nice "real" melodeon of similar construction.  But then he has over the years amortized the R&D/proto/production into what is now the finished product.  

The idea of "real" feel to an instrument is difficult one - especially with concertinas.  If we're basing instruments on lower quality instruments that may keep the price reasonable - but will they be frustrating to play given that the likely users of the MIDI 'tina are experienced players used to better quality instruments.  If using better quality instruments, who wants to modify a good vintage instrument?  One solution is to cooperate with one of the instrument makers - an easier proposition in theory with the Anglo, but difficult with makers of EC - in any case the length of waiting lists may well preclude this option, and may not yield an instrument with all of the capabilities to feel like a "real" concertina at a reasonable price and within a reasonable timeframe.  The price tag will have to include an element to recoup the outlay of R&D etc.  With MIDI accordions (not necessarily melodeons) there is an economy of scale to consider - there being far more accordion players than concertina players in the world.

Edited March 26, 2019 by SteveS

[SteveS]

3 minutes ago, alex_holden said:

The biggest thing that puts me off developing any kind of low-volume electronics product is the cost of EMC compliance testing. It can easily add thousands to the R&D budget, especially if you want to sell it internationally. Obviously not an issue if you're a hobbyist building a one-off for your own use.

Yes, EMC is one of the issues that contributed to my canning the MIDI 'tina project - it simply wasn't viable.

[Devils' Dream]

But when you do it.... 

 

[caj]

On 3/26/2019 at 8:45 AM, SteveS said:

Yes, EMC is one of the issues that contributed to my canning the MIDI 'tina project - it simply wasn't viable.

 

Hi, sorry I've been away,

 

I built a MIDI anglo a long time ago by pushing 30 SPST push-buttons into the holes of a Stagi, removing the action and the reeds.  It was luck, really:  I found a pack of 40 push buttons at a surplus store in California, and they were a perfect fit, skinny and just the right action.  

 

The rest was a bidirectional pressure sensor for the inside of the chamber, and a PIC microcontroller to output MIDI---that was back when a PIC ran about 1-2MHz and had no serial organ, so outputting MIDI required some carefully written assembly code.  It never worked in a very satisfying way (the bellows were very leaky and I wasn't reading the pressure sensor well) and eventually I purposed the buttons to other projects.

 

If I had to do it again, I'd probably skip the pressure sensors and experiment with microphones.  I bet if you sealed the bellows and drilled a hole in the pan, a cheap condenser mic right next to the hole would decently measure air flow from the hiss.  Two of them with flaps would give you push/pull.  But the big problem would be acquiring a nice set of bellows, that isn't part of a nice real concertina.

[JimMacArthur]

I built several 48-ley MIDI English concertinas a few years back (pictured) for quiet practice, and to save wear and tear on my old Stagi.  I went with the bellows-and-air-pressure-sensor route.  I custom-designed the keys to duplicate the force profile of the acoustic ones, because I wanted my practice tina to be as close to my acoustic as possible.  In addition to MIDI, the concertinas have a built-in wav synthesizer which plays back samples of my acoustic, amplitude-modulated by the pressure sensor, which is a pretty coarse approximation of what the bellows pressure really does to the sound, but as I said, this was just for practice.  I did take the time to make the instrument feel solid and look beautiful, because I feel it's important.  I never intended to sell these, so I could go with very labor-intensive construction techniques.

 

Then, two things happened.  My kids grew up and there was much less need for quiet practice.  But also, I found myself favoring my acoustic more and more, to the point where the electronic ones just took up shelf space.   I must say that it really surprised me -- I'm hardly an acoustic snob -- but, dammit, the electronic simply doesn't have the soul of the acoustic.  So I'm just posting by way of a warning -- I designed something with the same tactile response as my acoustic, but I suppose I fell down in the sound generation part.  A wav player is a decent starting point, but I suspect that nothing short of full-on physical modeling will create an instrument whose responsiveness approaches mechanical reeds.

[Roger Hare]

Posted in the wrong thread! Content deleted.

Edited August 19, 2019 by lachenal74693