In order to assist you in making the correct choice of instrument please take some time in analyzing your couplers/registers of both the bass and treble sides. Some of your registers are called “transposing couplers”. Some will give you different pitches and/or combinations of pitches (see diagram). In order for you to play a certain musical phrase/passage in your piece, you might need to apply a register in order to obtain a true pitch of what has been written, or simply have the right “sound colour” for the passage in the piece that you are playing.
Please note that usually block reeds in tone chamber are marked with an empty circle on the register, and reeds out of tone chamber are marked with a filled circle on the register. Also, not all accordions have a tone chamber called “cassotto”.
Register Stop Classifications
The pitch of a single bank of reeds is traditionally defined in a similar manner to the organ stops of a pipe organ. A bank that sounds at unison pitch when keys are depressed is called 8’; (pronounced “eight-foot”) pitch: alluding to the length of the lowest-sounding organ pipe in that rank, which is approximately eight feet. For the same reason, a stop that sounds an octave higher is at 4′ pitch, and one that sounds an octave lower than unison pitch is at 16′ pitch.
Most reed registers are normally in relative octave tuning, but rarely, some instruments have a reed bank tuned to a Fifth relative to the 8′ stop (or some octave of that). This is a similar arrangement to stops for a pipe organ.
The icons below indicate the classification and descriptions of the various registers:
4’ stop – this is the highest reed rank. Not all accordions will have this reed rank.
8′ stop – this is the basic middle reed rank. It is one octave lower than a 4′ reed rank.
8′ stop – this is another middle reed rank, the upper tremolo rank. It is usually tuned slightly higher than the basic middle reed rank. Not all accordions may have this reed rank.
8′ stop – this is another middle reed rank, the lower tremolo rank. It is usually tuned slightly lower than the basic middle reed rank. Usually only included on special “musette accordions”.
16′ stop – this is the lowest and deepest-sounding reed rank in the reed chamber. It is one octave lower than an 8′ reed rank.
Register switches control how contrasting timbres are produced. They control which reed ranks are enabled (opened up) or disabled (closed off), in a similar manner to the register switches controlling the organ stops of a pipe organ: a single reed rank, or several simultaneous reed ranks. Unlike a pipe organ, only one switch can be active at any given time. Here are a few examples of right-hand manual switches on a typical large accordion (Smaller boxes with fewer reed banks may have fewer switches or even none).
Below are all the icons, their nicknames, registers and a description of their sound:
Stops in use
Piccolo 4’ – thin and reedy tone.
Clarinet 8’ – a round tone, pure and free of harmonics.
Bassoon 16’ – a full, smooth tone.
Oboe 4’+8′ – a thin tone.
Violin 8’+8′ – round tone, pure and free of harmonics plus one reed tuned slightly higher.
Musette (Imitation) 4’+8’+8′ – an imitation musette sound. Found in most accordions.
Musette (Authentic) 8’+8’+8′ – a strong and distinctive sound, built for special “Musette accordions”. Tremolo.
Organtype (Organ) 4’+16′ – a slightly reedy quality.
Harmonium 4’+8’+16′ – like the Oboe stop, but heavier because of the added 16’ reed rank.
Bandoneón 8’+16′ – characteristic round, mellow accordion sound.
Accordion 8’+8’+16′ – like the Violin stop, but heavier because of the added 16′ reed rank.
Master 4’+8’+8’+16′ – the loudest and fullest accordion sound.