Determine the Key of Your Instrument

After you have determined that you have a Chemnitzer-style concertina (not an English, Irish, Anglo-German, Duet, or Bandoneon), you should determine what "key" the instrument is in.

The Czech Area Concertina Club have a convenient decoding sheet: see How to Determine Your Concertina Key and How to Play with Concertinas in Other Keys.

If you have a 52-button or "104-key" (which really means 104 notes - 2 for each button), you should have a button on the right side that looks like a circle with a crosshairs through it (a "coda" symbol).  The note that sounds while you draw (that means pull the bellows open) while pressing this button is the "key" of the instrument.

If you don't have that button - you need to refer to the decoding sheet at the CACC, because it is complicated.  You probably have a C, E-flat, B-flat, A-flat, or C-sharp concertina.  This affects who you can play with.  C concertinas are the most common.  I don't know why there are different keyed instruments, but I can guess.  All of these instruments have the same key patterns: all the buttons and reeds are arranged the same way (with the Scheffler'sche Lage, or the standard "Scheffler Key" layout) [I also understand that there is an American Scheffler layout and a German Scheffler layout].  However, the actual pitches that sound will be shifted away from those of a C concertina.  A B-flat concertina will sound a whole step lower, the notes of the E-flat will be a minor third higher, the notes of the A-flat will be a major third lower, and the notes of the C-sharp (or D-flat) will be a half step higher.

Don't worry if you don't know what any of that means.  All Chemnitzer concertina music can be played by any Chemnitzer concertina, no matter what key it is in.  However, concertinas in different keys can't play the same music together (obviously, because the notes that come out when you play will be different).

You could rewrite the music and transpose it for the non-C instrument.  Or, you could transpose it in your head (super difficult).

Or you can play with other instruments that are also in your key, which is my guess for why there are different keyed concertinas.  The concertina I am using is a B-flat concertina.  This means I can play with other "transposing" B-flat instruments, and we can read from the same music without having to do any transposition.  Trumpets, Baritones & Euphoniums, Tenor Sax, Bass Sax, Soprano Sax, Clarinets are all in B-flat (possibly Bass Trombones, I'm not sure).  Alto Saxophones are in E-flat.  Tenor Trombones, Flutes, pianos, string instruments, guitars, are all in C.  French horns are in F, but can be played as if in B-flat.  Tubas commonly come in various pitches, B-flat and C and also E-flat and F.

A note on transposing instruments.  A "transposing instrument" means that the music written for that instrument has been transposed for the musician.  The reason for this is because brass instruments used to have removable crooks that changed the key for you.  This meant you could use the same fingering pattern for whatever key you are in.  Nice!  Speaking as a trumpet player, normal trumpets are in B-flat, but some classical music may call for a C trumpet, or a D trumpet, or an E-flat trumpet  If I play a C scale on any of those trumpets, it will come out in B-flat, C, D, or E-flat, depending on the trumpet I am using.  When I read a C in the trumpet music and I play what I call a C, the note that sounds will be a B-flat, C, D, or E-flat, depending on which trumpet I am using.  The finger pattern I use for my "C-scale" is actually the notes of the B-flat scale if I am playing a B-flat trumpet.  

To make things easier for me, the composer or music arranger has writes my part to account for this (its standard musical notation - take a look at a musical score, and you will see all the instruments in different keys - for instance, Beethoven's 5th Symphony in C Minor, 3 flats.  Note the Clarinetti in B, which means a Bb clarinet.  The part written has one flat - the key of D minor, one step above C minor, as expected).  

SO:  if a piece of music is in the key of D, (two sharps), music for the C trumpet will also be in the key of D with two sharps.  HOWEVER, if the composer has written for a B-flat trumpet (the norm), the B-flat trumpet music will be written in E (four sharps) in order to account for the difference in pitch. BUT, if the composer has written a part for a D trumpet, the D trumpet music will be in the key of C.  Each of these trumpets will play the same notes, but will be moving their fingers differently.  For trumpet players, keys with fewer sharps are easier to play, so the D trumpet player would have the easiest finger patterns.

The same thing applies to Chemnitzer concertinas.  The fingering is the same for any instrument, but for us to play music together, we must transpose the music for the non-C concertinas, or non-C concertina players must transpose the music in their heads, or play the music only with other instruments in the same key.  Or you can make everyone else transpose their music to your instrument.

Update:  I found another tool on the United States Concertina Association website, concertinamusic.com for determining the key of your instrument.  They have some audio of the pitches of the various "keys" to test your concertina against, in case you don't have a piano or know how to play a piano, this will be very helpful.