Accordion Terminology

This is a list of words associated with the accordion and their meanings. It has been separated into two sections for easy reference; one for parts of the accordion and one for general music terms that easily relate to the accordion. If you have a word to add to the list, please send it to us.

ACCORDION PARTS (Listed in Alphabetical Order)


Air Button

The air button operates a valve that allows the bellows to open and close without the accordion making any sound. It is usually found on the side of the bass board, or is the very top bass button.

Back Strap

This joins the two shoulder straps together, on the accordionists back. Some players feel it holds the accordion in place more securely, and takes pressure off the back.

Bass Switches

See Switches

Bass Strap

Usually made of leather, this goes from the top to the bottom of the accordion, on the bass side. The strap is positioned over the wrist, providing a support for the left hand while playing the bass buttons. Its main use is to enable the player to move the bellows in and out.


The bellows are the "heart" of the accordion. They create the volume by forcing air through the reeds. Controlling the flow of air with the bellows for expression and dynamics is one thing that is unique to accordions.

Bellows Clips

The bellows clips keep the bellows closed when the accordion is not in use. They are on the top and bottom of the bellows.


See Tone Chamber

Chin Switches

These are a type of treble switch. They are found on top of the accordion, above the treble keyboard. They do the same thing as any other switch, but are very easy to use, because the player does not have to move their hand to change switches.


See Switches


The grille covers the keyboard's treble valves and mechanisms. It is used to decorate the accordion, and usually displays the brand name and/or the logo of the manufacturer. It is common to see brightly coloured grilles with jewels and different coloured trimmings. The grille is usually "vented" to allow a louder treble sound. Occasionally, however the grille is used as a muting mechanism.

Master Bar

This is an optional type of On/Off switch, located on the outer edge of the treble keyboard. It is operated by a push with the heel of the hand, automatically opening all the register slides. After release, it springs back to its original position. This allows the player to introduce all the reeds without taking fingers off the keyboard.


The reed produces the accordions sound. It consists of thin steel, which is riveted at one end of the reed plate (usually made of aluminium). The other end of the reed is free to vibrate in and out of the slot, when air pressure is supplied from the bellows. The reed plates are mounted on reed blocks, which are usually made of poplar wood. Reeds have leathers to moderate the airflow.


Valves are the padded bars which open and close sound holes and are operated, through valve levers, from the keys or buttons. These sound holes are located on the treble side of the instrument, under the grille.


The pitch of a reed is determined by the speed at which it vibrates. This speed is governed by the length and thickness of the reed. The longer and thicker the reed, the slower the rate, and consequently the lower the pitch. A reed does not vibrate faster when greater air pressure is applied, but moves further in and out, creating a greater volume.

Quality of Reeds

The reeds are the most vital part of an accordions sound quality. They belong in four categories, listed below. Note: These categories may vary from source to source.

Commercial: These are the least expensive reeds, and are manufactured almost entirely by machine. They are smaller than others of higher quality. The aluminium reed plate is also of a lesser quality, and often has a dull finish.

Hand Finished: The reed plates will have some degree of shine, but the finish of the plate will not have a finely smoothed finish. The manufacturer mounts the reed tongue by hand.

Tipo A Mano: These reeds are usually made on a larger plate, and in some cases the reed plates are the same size as those used to manufacturer Hand Made reeds. The phrase "Tipo A Mano" means "Imitation Hand Made Type". The better Tipo A Mano reeds (made of superior steel) with good hand work, can be nearly as good as most Hand Made reeds.

Hand Made: This is best cut of reed. The reed plates are hand cut and made of the best aluminium, called Duraluminium. They are finely finished to the point where they shine. The reed tongue of the Hand Made Reed is often blue on the sides of the square blue steel base, because the steel is heat tempered in strips. The base of the reed is often obscured by a layer of wax, which is applied during the installation of reeds onto reed blocks. This characteristic tells you that the reed is hand made.


See Switches

Shoulder Straps

The shoulder straps are used to stabilise an accordion as it is being played. There is one strap for each shoulder. These straps make it possible for a musician to play when standing.

Register Slides

These are thin strips of metal, that slide in between the reed banks and the valves. They are designed to open and shut the banks of reeds. A mechanism connects these slides to the switches.


The function of a Switch is to open or close one or more sets of reeds, via register slides in the reed blocks. The more reeds in an accordion, the more switches become available.

Treble switches: There are two types of switches that are on the grille: the automatic and the On/Off (push once for On and again for Off). Each push button of the automatic switch opens specified slide registers and closes others (according to the setting of the combination of reeds, see below).

Bass Switches: Most full-sized accordions are now equipped with one or more switches on the bass section also. These are normally in a vertical row, along the inside of the bass board. As with treble switches, there are two types; automatic and on/off. The automatic type of switch is sometimes called a pre-set switch, and it involves a great deal more mechanism than the simple on/off type lever switch. There can also be switches located near the air button.

Note: Both Treble and Bass Switches are arranged in different orders on different makes of accordions.

Quint Switches: The individual incorporation of the perfect 5th (which is actually a 12th; an octave higher plus a 5th higher again) to every note on an accordion, giving a Pipe-organ type sound. This especially suits Russian or Pipe Organ music. This switch is usually only found on larger accordions.

Most full-size accordions have four sets of treble reeds, and some have five. With various combinations of these there can be fifteen or more switches on the grille. Each select a different combination of reeds by opening and closing slides.

For example, these are the combinations available with automatic switches on a three reed accordion:
Switches can be doubled up in other places on the accordion:

Master Bar
Chin Switches

Thumb Straps

The thumb strap is for the thumb of the right hand, and is mostly used on lighter concertinas and bandoneons, where shoulder straps are not needed.

Tone Chamber

The tone chamber is the translation for the word "Cassotto" (meaning "box") which is what a Tone Chamber constitutes; a box into which a set of reeds is placed. Cassotto is the general term used for any instrument with reeds in a chamber. However, the term "Double Cassotto" can be used when there are two sets of reeds in the chamber. A Tone Chamber gives an instrument a rich, full sound.

Treble Switches
See Switches

Treble Keyboard (Piano Accordion)

The treble keyboard has the same layout as the piano. The lowest note is at the top when you look at it from the front. For further information, see Types of Accordions and how they work.


These are what let the air into the reed. See REEDS for further information.

Wrist Straps

These help hold the accordion in position, and like the bass straps are usually made of leather. They can be worn on either on the right or left hand. Like thumb straps, they are also used on smaller concertinas and bandoneons and small accordions.



Many musical terms can be related to the accordion. These are definitions of the most commonly used terms. This list also includes terms which specifically relate to the accordion.


This is when the player suddenly pulls on the bass strap or pushes on the side of the bass board with his/her arm while pressing a note, which creates a short sharp sound. Good co-ordination is required to get the timing of an accent exact.

Alternating Bass

To play this, a root note (fundamental) is played, then a chord of that root note, followed by the fundamental dominant (5th) of the root note, and back to the chord of the root note. A simple example is: C, C Major, G, C Major.

Bellow Shakes

The bass arm pulls quickly in and out causing a "stuttering" effect. There are many types of bellow shakes, which give different effects:

Duple Bellow Shake

In the space of a beat, a note is sounded twice. The duple bellow shake is played by creating a "hinge" with one side of the bellows and only opening the bellows from the opposite side.

Triple Bellow Shake

In the space of one beat, a note is sounded three times. The bellow movement is In, Out, In and vice versa. This can take a lot of co-ordination to get the feel of the rhythm because the pulse (the first in or out) changes bellows direction every time.

Quadruple Bellow Shake

In the space of one beat a note is sounded four times. The bellow movement is In, Out, In, Out. This bellows shake can sometimes be played using the four corners of the bellows, where the bellows are moved in a circular motion, creating the feeling of four counts. This, however takes a long time to learn!

Converter Bass

This is a bass system which can play both standard and free bass, by using the Bass Switches. An accordion with a converter bass is possibly the most versatile accordion available.

Crescendo (gradually getting louder)

This is a term familiar to most musicians, but the accordion is one of the best instruments on which to play a crescendo. Pressure is gradually increased to the bellows, which increases the volume.

Decrescendo (gradually getting softer)

This is the opposite of the crescendo, and again the accordion is one of the better instruments on which to perform it. By gradually decreasing pressure to the bellows volume also decreases.


A Diatonic accordion has two reeds tuned to different pitches for each note. The direction of the bellows determines which note is produced. For detailed information see Types of diatonic accordions and how they work.

Double Action

The pitch of the note is not affected by the direction of the bellows, eg: C is the same note on the out bellows as it is on the in bellows.

Free Bass

Unlike the stradella system, all the bass buttons play individual notes. This gives the accordion a fantastic range of notes. Organ and piano pieces can be played without needing to be arranged. Free Bass is used by many baroque and classical players.


Please refer to Frequently Asked Questions for a full explanation.


Musette is a sound produced by specifically tuning the reeds of an accordion higher or lower than normal. It is very common in traditional French music. Musette can also be called "Tremelo".

Stradella Bass

This is the traditional bass style of the accordion. There are up to three (and sometimes four) rows of buttons which are single notes, and up to four rows of buttons which are fixed chords (3 notes play when one button is played).
© 2024 Accordions Worldwide • All rights reserved. To comment on these pages, e-mail the webmaster.