The bass clarinet in Bb is a small bore model, similar in acoustical concept to the bass clarinets most commonly manufactured in Germany (by such makers as Wurlitzer). This produces a compact, focussed, flexible, singing tone with a more clarinet-like quality than the more familiar French style bass clarinet, and with all the power and projection one would ever need.
A further advantage of this bore/mouthpiece concept is that it eliminates or greatly reduces the problem of the instrument "fighting back" in the middle of the second register (apparently caused by acoustical impedance mismatching between the instrument and the vocal tract), which afflicts many players of the French bass clarinet.
While most customers these days would require an instrument with range to bottom C, a "short" model to Eb is also offered. A further option is a convertible model, with a removable low C extension section (which has the advantage of greater portability).
The bell is a of the clarinet type, with a separate, detachable U-tube (of wider angle than on conventional bass clarinets); this allows the possibility of omitting the U-tube and playing with the bell pointing downwards, for maximum clarity and strength of the bottom notes (though with the low C model, this requires the use of a fairly high stool).
Mechanical innovations include a triple register/throat Bb mechanism, producing both a clear Bb and accurate twelfths (eliminating the universal problem of the sharp middle B). For the extended range model, normal keywork is three right thumb keys for bottom D, C# and C, with an additional D key for the left hand little finger. An alternate left hand Ab/Eb lever is also standard.
A dedicated German bass clarinet
mouthpiece (considerably smaller than the French type) must be used; a
high quality example is included. Reeds can be purchased from companies
in Germany, or from Legere Reeds
German bore bass clarinet
in Bb, range to low C