Little John

There's more than one convention. The one I use, which seems to be fairly widespread, is based, I think, on the notes on a piano. So middle C is C4. The B immediately below is B3 while the B almost an octave above middle C is B4. The next octave up runs C5 - B5 and so on in each direction. LJ

David - based on your figures I calculate these bellows open to about 83 degrees. LJ

Thanks for sharing this. It was also interesting to see the use of English concertinas in Bolivia. (That was in the video that came up next, not that I understood much of it!)

This is, coincidentally, the size of the cards on the Crabb. It would give less than 5% extra air over 1" cards, but for no real cost. Add bellows that extend to 100 degrees and you get 10% more air over 1"/90. 110 degrees look like the goal to me, and if you've already got 104 from virgin bellows you're probably almost there. Incidentally, I've added another one to my sample set - a Wheatstone baritone, circa 1900, with 1" cards and opening to 97 degrees.

I've done some (literally) back-of-an-envelope calculations. I simplified the arithmetic a bit and made some assumptions. Principally I assumed a 6 1/4" instrument would have bellows measuring 6" AF, and that the folds opened to 90 degrees. On this basis, and starting from a card depth of 1", increasing to 1 1/8" gives 9.3% more air and increasing to 1 1/4" gives 18% more air. However, leaving the card depth at 1" but increasing the fold opening to 110 degrees gives a 20.5% increase in air; while increasing card depth to 1 1/8" and the fold opening of 110 degrees gives a whopping 32% increase in air. Don't take these figures as gospel. Someone else might like to do more accurate calculations, but I'm pretty confident of the trend they show. Taken together with the comments about stability it would seem best to put effort into increasing the opening rather than the card depth. How reasonable is that 90 degree assumption? From the sample of five available to me three didn't quite make it to 90 degrees and one made it to 102. The real exception was my 1934 Crabb, which opens to about 114 degrees. Maybe that's why I've never found it short of wind, despite having only 6-fold bellows.

I've always assumed the purpose of these little discs was to prevent the noise of the buttons hitting the action board.

Does it have aluminium reed frames? LJ

I had a Crabb 55 with the chevron layout for a couple of years. It didn't take long to get used to it and I didn't have any trouble swapping between the Crabb chevron and the Butterworth arc. But I couldn't really get on with the physical size of it. At 7 1/4 inches it didn't feel concertina-like to me! Your 67 must be much bigger. LJ

Thanks for this. It certainly does go low! (Eb rather than E.) I'm always intrigued by the seemingly random way Crabb added the extra notes. The sixth column under the little finger makes sense, but the Eb - Bb transition looks awkward. I'd probably consider swapping the E2 and Eb2 reeds. I also detect a bias towards the flat keys. This example omits F#2. Other extended Crabbs, e.g. 57 or 58 button versions, add just Bb2 and F2. Once you've had time to familiarise yourself it would be interesting to hear how you find the transition from 35 to 67 buttons.

Haha! I'm with you on this. The one that really gets me is the "shock absorber" on cars etc. In fact it's a shock transmitter - it only "absorbs" low frequency motion; not high frequency shocks. "Watershed" is OK, though - it's the high point of a saddle (topologically) that sheds the water into the valleys either side. Sorry - this is getting off topic; which I initially thought was going to be about what people mean when they talk about "miniature" or "semi-miniature" concertinas. To me, "very small" or "small" would be more accurate. I think of miniature as meaning scaled down (like a toy steam engine, for example), whereas "miniature" concertinas preserve (more-or-less) the button spacing. They just have fewer buttons in a smaller box.

Congratulations! It would be interesting if you could post some photos and a description of its note range.

Wow! That second one is huge. Only two extra buttons and yet a massive increase in size. Any idea why? Does the big one go much lower, or what? My experience of Crane duets is that they seem to go: 35 and 42 button - 6 1/4"; 48 button - 6 5/8", 55 button 7 1/4". These are what might be called the "standard" instruments. Once you go into a greater number of buttons there doesn't seem to be much of a standard layout with extra buttons above or below, or outside the normal five columns and even under the LH thumb.

Hi wunks. If your instruments have metal ends, the tiny screws or rivets within the button pattern will be to hold the wooden bushing board in place. The metal is too thin to attach felt bushes, so a wooden board is needed. Wooden ended instruments don't need this - they are thick enough on their own. If you can see other screws, the heads of which do not come through the end plates, they will most likely be to prevent too much flexing of the end plate. I've seen that on at least one instrument. LJ

Thanks for introducing me to Heartstrings and Caitlin nic Gabhans. It's a lovely tune which I might have a go at myself. Do you have many tunes that go this low? I have a handful or more that go to the B just below middle C, but I can't think of any tune that goes lower. LJ

Exactly. So what would a violin-type soundpost add?