Accordions are normally fitted with up to five banks of reeds and are referred to as ‘voices’. In a 5 voice instrument a common configuration of the reeds is depicted as shown below and is what is often displayed on the instrument’s tone change switches.
The footage (‘) sign refers to pipe organ standards where 8′ is the middle/standard pitch, 4′ is one octave higher and the 16′ one octave lower.
The three reeds on the centre, vertical line are all tuned ‘straight’ ie. they are all exact octaves apart while the three central reeds, on the horizontal line are offset. The reed on the extreme right is pitched slightly higher than the central reed and that on the extreme left, slightly lower. (In some tunings both offset reeds may be ‘sharp’ in relation to the straight tuned 8′ reed).
The effect of offsetting the reeds is to create ‘beats’ (a vibratory effect) and the degree to which this is applied is referred to as ‘wet’ or ‘dry’ tuning.
Instruments are normally 2, 3, 4 or 5 voice and by mixing the reed combinations different tone affects are obtained. The following are examples of reed configurations and some manufacturer’s names.