The brio, that vibrato that changes everything on the accordion

The brio swing, American, celestial, musette, semi-swing, dry, ... What is it?

Within the wide range of sounds that the Accordion possesses, there is a typical vibrato sound generated by two medium voices tuned at different frequencies.

The brio corresponds to the management of this vibrato.


I- The technical part:

Vibrato is created by juxtaposing two sounds of slightly different frequencies.

Let's take as a reference an A medium with a frequency of 440 hertz, i.e. 440 oscillations per second.

Let's juxtapose a second A with a frequency of 442 hertz.

The human ear will then perceive 2 beats per second, which correspond to the 2 dropouts (442 - 440 = 2) of the frequencies.


A little aside: Let's play with our ears!

Listen to a fly flying and try to approximate the sound it makes.

If the sound of its flight sounds like a low-pitched G, for example, you can deduce that the fly makes about 196 wingbeats per second.


You can also carry out this experiment with a combustion engine (scooter, car, etc.). You will then have to transpose the beats/second into rpm...


II- The historical part:

This vibrato was already used in the romantic period by organs and later by harmoniums. This register was called "celestial".

The Accordion will quickly adopt this vibrant sound from the beginning of its popularization to make people dance or to accompany songs.

The ballroom accordion will always use this vibrant, singing sound that is so popular.

This festively coloured tremolo will also give the accordion a great sense of power. Microphones were not yet in use.

After the first world war, jazz from the United States of America arrived in France. It was also called Swing.

Some accordionists of the bal musette were attracted by this new musical genre and integrated it into the existing repertoire.

Towards the end of the 1930s a new, typically French musical style could be heard in Paris, inspired by both Musette and Swing or Jazz.

The accordionists who adopted this new style had the sound (brio) of their accordions modified by removing the strong tremolo used previously.

A new accordion sound was born. It would be called the "modern", "American" or "swing" sound.


III- The different shades of brio:

The brio is the effect generated by the difference in frequencies between 2 medium voices.

It ranges from 0 to about 9 hertz on a medium A.

Accordionists have always sought to name each nuance of brio with varying degrees of precision.

A difficult exercise. As difficult as defining a shade of colour: light blue, sky blue, pale blue, azure blue, horizon blue, etc.

The new sound that appeared at the end of the 1930s was therefore called "modern" "American" or "swing". It corresponded to a very light brio with very little difference between the two voices: from 1 to 2.5 hertz on the A medium.

Over time, definitions have become more refined. The name "modern" disappeared. The name "swing" was given to a very tight brio from 1hz to 1.5hz and the name "American" to a slightly more vibrant brio from 2hz to 2.5 or 3hz.

The old traditional sound was then called "musette" for a tremolo on 3 voices (see our article on the musette sound) or "celeste" for a tremolo on 2 voices. Each of these two sounds encompassed many shades of brio ranging from 4 to 9 Hz.

At the end of the 1970s the diatonic accordion made a comeback.

In turn, the strong tremolo that it had previously retained is removed and the new, less vibrant sounds are adopted with brios ranging from 0 to 2.5hz.

New names will appear: "half-swing" "dry" etc.

Dry brio is in fact the absence of brio. The two voices are tuned exactly to the same pitch. No tremolo is perceptible except for the occasional slight phasing.

The "half-swing" brio will be interpreted in two different ways:

1 - The historical approach which understands the "swing" sound as a suppression of the tremolo and therefore the "half-swing" would suppress a little less and be a little more vibrant than the "swing".

2 - The new approach which understands the "swing" sound as a slightly vibrating brio compared to the "dry" sound and therefore the "half-swing" would vibrate a little less than the "swing". This second approach seems to be in the majority today.

The definitions and names of the different shades of brio remain fluid. They have not been standardised.

Every nuance of brio can nowadays be named to the nearest half-hertz...sometimes differently from one workshop to another.


IV- The precision of brilliance:

It is possible to achieve a brio with a high degree of accuracy up to 1/2 hertz if the instrument allows it.

These are the main categories of brio:

- The "dry" tuning where both voices are perfectly in tune

- The low-vibration "dry swing" "tight swing" "muted half-swing" "half-swing" "swing" "swing plus" "American" "American plus" etc. which range from 0.5hz to 2.5hz with all the nuances in between.

- The so-called "Italian" medium brios from 3hz to 4hz

- Vibrant "celestial" brios, from 4.5hz to 9hz, from "light celestial" to "celestial +++".

- Today we also speak of "musette" brio, which in fact corresponds to the very vibrant "celeste". The name "musette" was previously reserved for sounds generated by 3 medium voices.



- Brilliance, beyond its technical aspect, is first of all a feeling.

The same brio setting will give different sound colours depending on the instruments used. Beyond the brio, each accordion has a personal timbre.


- Accordion makers prefer to use a more technical and precise language. They express themselves in cents or hundredths of semitones (equal temperament).

One cent = about 0.26 hertz at the A medium.

A breeze at 2hz will give about +8 cents.


Our advice for choosing your brio:

The various names and qualifiers attributed to brio to describe its sound colour are the first approach to defining a more or less vibrant sound.

To choose the right brio for you, talk to your tuner or accordion maker and don't hesitate to quote examples of artists or sound samples you like.

Your tuner will be able to define it with precision for a rendering as close as possible to your expectations.