Heckelphone. Nominal pitch: C basso.

Technical description: Dark stained maple wood with silver-plated keys and wide ferrules at all three sockets. Built in four sections; there is a separate section between the bell and the lower joint which contains the keys for lowB♭ and A. The instrument can be assembled and played without this fourth joint, reducing its size and making it more convenient for the player when the lowest notes are not required. The bell is bulbous with a large vent-hole at the front. Segments cut out of the lower two ferrules and corresponding metal 'teeth' above the tenons ensure that the instrument is always put together straight. A similar arrangement on the middle joint has the 'tooth' emerging from the ferrule and fitting between two slugs screwed into the top section. A metal stand to take the weight of the instrument fits into a unit screwed to the base of the bell, this ensures the base of the bell is not blocked during playing. The axles for the R4 keys are mounted away from the instrument with the key-cups operated by R2 and R3 underneath. The 'plates' for L and R 1, 2, and 3 are small buttons surrounded by rings (2 rings for L3), these are of individual design. There are automatic octave keys with two touches which have the same action. The lowB♭ and A keys lie next to each other and operating them with the right thumb is very similar to operating the bottom notes on a Heckel-system bassoon.=, L0: TP; 8. L1: PP; 8dup. L2: P. L3: P; Dtr. L4: G♯; lowB; Fdup; E♭ dup. R0: sup; lowB♭; lowA. R1: P; TPdup. R2: P. R3: P; F. R4: lowC; C♯; E♭. Keymount type: pillars. Repair History: The original conservatoire mechanism has been replaced with thumbplate; the pillars for the upper-joint lever remain as does the linking key on the lower joint. The TPdup key (which must have been added as part of the change to thumbplate mechanism) has been extended or repaired after snapping off. The corking on all the tenons has been 'tightened' with waxed thread. The present playing stand is a modern replacement, there are marks on the bell indicating a differently shaped stand but of similar design. There are marks at the back of the lower section indicating that the thumb support has been moved about 10cm down the instrument.