The idea of the full double Cimbasso came about after years of struggling with stuffiness on a Compensating Eb Tuba. It gives the same fingering system as a Compensator but will a much more open feel. The Double is built with the MJC piston valve section, each being custom built, in house here at MJC, to suit the instrument.
The Instruments built so far are Eb/Bb but the design is such that an F/C can be built also.
Each side of the instrument is a true, 4 valve, non-compensating system. A change valve is on the left hand and acts like a compensating 4th valve.
The reality of this allows for just two valves to be used for the semitone above the fundamental as opposed to 7 valves on a standard compensator.
With the addition of the 4th valve on the little finger, valve notes can be utilised on the longer instrument instead of open pedals, thus enhancing the tonal palate in the low register.