Richard Mellish

In at least one place in one tune where the first note of a phrase is the same as the last note of the previous phrase, I play one phrase on pull then change to push with the repeated note on a different button.

Looks like I need to put it back together so I can (a) confirm that it does actually work, and if so (b) post a picture on here. I have a fair amount of experience with discrete components (going back to valves!) and small-scale integration, and at the software end with BBC BASIC, but very little in between, hence my choice of an off-the-shelf MIDI interface rather than a Raspberry Pi or the like. The rest then followed from that. Your plan is an illustration of there being more than one way to skin the proverbial.

Here is the description. RM MIDI concertina.pdf

Can't do a pic at the moment. I did have the two ends connected by the bit of coat hanger, but it needed a bit more work and the ends are separated at present. I'm attaching a PDF of the circuit but it may not make much sense without the description of the rest of the system, and I've realised that that needs an update. I'll post it ASAP. MIDI concertina pressure circuit.pdf

I'm not sure whether it should be called a strain gauge or a load cell. Anyway one of these https://tinyurl.com/2t6txzpd . Then a quad op-amp and a few transistors to provide polarity output (needed for a Anglo keyboard) and an analogue voltage to control amplitude. I can provide more info if desired, but perhaps on a different thread.

I remember reading about players of the English concertina somewhere in South America. A quick Google has found me this: https://www.concertina.net/forums/index.php?/topic/9801-concertinas-in-bolivia/

On my (still essentially proof-of-concept rather than a mature design) MIDI concertina, I have tried several arrangements in seeking the right amount of flexibility between the ends. Real bellows give a fair amount of flexibility about axes through the plane of each end but very little about an axis from one end to the other. The best arrangement that I have found so far uses a short piece from a wire coat hanger, bent into a U shape.

I try to minimise what John Vernon described as "Anglo player's shake", i.e. lots of bellows reversals, by using alternative buttons. There is much more scope for this on a 40-key (or, I suppose, on a Jeffries 38-key, of which I have no experience) than on a 30-key. I do this partly for more legato and partly out of simple cussedness. People who see me play sometimes think I am playing a Duet. I should mention that I regard this as a matter of personal preference, not a matter of right and wrong.

Where are you located?

Could you post a picture please?

These are clear illustrations of the gap between what AIs know (a lot) and what they understand (nothing).

Number now noted

Seems to require Facebook login.

What matters is the amount of air that leaks in proportion to the amount that does something useful in making the reeds sound. If it's a small proportion I wouldn't worry about it. If it makes a significant difference to how many notes you can play before you run out of air it's worth investigating.

Isn't there someone in that area able to give an estimate for (a) the cost of restoring this one to good order and (b) its value when restored?