My first post. I have just got hold of a Lachenal concertina. I play a Wheatstone English treble, and have a Jones anglo. But this Lachenal is different from those two types. Is it a duet? (never seen a duet in the wild). It has no air button, plays same note in and out, is same size as my English more or less, and has the looks, from a distance, of an anglo. I googled images of a duet, but they all seem to have more buttons than this one. I am very very grateful if some knowlegeable souls could tell me what it is, or in fact anything at all about it. The serial number is 1780, and the other side has the Lachenal logo of London. There is a worn thin kind of hessian inside the wooden ends. It came in the original box too, with a large metal ring on the lid. It leaks pretty badly through the reeds, although the bellows seem to be in fine shape.
Thank-you much in advance, Bill.