The LefreQue has been developed universally, nevertheless there are a number of recommended combinations for each instrument. Below you can find the recommended combinations. These combinations are derived from years’ worth of research and the physical dimensions of each instrument.
You can improve the sound of the flute in three places: a sound bridge on the connection between the head joint and the body, between body and foot and between head joint and the crown. The most is gained at the connection between the head joint and the body. For a flute a LefreQue of 33mm or 41mm is recommended. The connection between head joint and body and body to foot requires a 70mm elastic and for the connection between crown to head joint requires a band of 55mm.
The clarinet has four connections that may be improved with a sound bridge: the most improvement may be achieved with a 33mm LefreQue between the mouthpiece and the barrel. A 33mm LefreQue can also be placed between the barrel and the upper joint and between the upper joint and lower joint. The last improvement may be gained with a 33mm or 41mm LefreQue sound bridge between the lower joint and the bell. In all cases you will need 85mm elastic bands.
The biggest improvement with a saxophone is achievable at the connection between the mouthpiece and the rest of the instrument. Due to the sound absorbing cork, that creates an airtight connection between the mouthpiece and the rest of the instrument, there is a lot of improvement possible in the frequency transfer.
For Soprano and sopranino saxophones is the 33mm LefreQue with a 45mm band the best fit. For Alto, Tenor and Baritone Saxophones a 41mm is more fitting, especially if the cork is a bit longer. To use with the sound bridge the 55mm elastic bands are the best fit. You can also place a sound bridge on the connection between neck and body. The 55mm Xtra Curved LefreQue is the best fit for this with 2 Special 70mm bands to attach it. For the connections between body and bell curve and bell curve and bell the LefreQue 33mm or 41mm is recommended together with the Special 150mm band.
Trumpet, Flugelhorn and French Horn
A 33mm LefreQue with a 45mm band or a 41mm LefreQue with a 55mm band fits the best on French horns, Flugelhorns and trumpets.
Trombone and Euphonium
For trombones and Euphoniums a 41mm LefreQue with a 55mm band or the 76mm LefreQue with two 55mm bands is recommended. The sound bridge is placed over the connection with the mouthpiece.
The tuba has one connection that could be improved with a LefreQue: Between the mouthpiece and the leadpipe. The 41mm, the 76mm or the 106mm LefreQue with two 55mm bands is recommended for the tuba.
Oboe and Bassoon
A special sound bridge has been developed for bassoon and oboe with a higher curve, which means that the sound bridge fits effortlessly between the reed and the instrument. The 55mm Xtra Curved could be fitted with the double reed band. A second LefreQue could be placed over the connection with the bell. For the Oboe a 41mm with a 85mm band is recommended, for the bassoon a 76mm Lefreque and a special bassoon band.