Me playing a strange woodwind instrument - a Kaossilator vocoder-preset - with a microphone during an Ambiosonics live jam two years ago. (You may find recent Ambiosonics tunes in Soundcloud under "Ambiosonics")
There were lot´s of questions about that sound.
Did a research and found out that it comes close to the voice of a Heckelphon. An forgotten instrument form the last century.
Nice example for the Disquiet Junto project "ancient instruments"
This is what Wikipedia says to the Heckelphone:
"The heckelphone (German: Heckelphon) is a musical instrument invented by Wilhelm Heckel and his sons. The idea to create the instrument was initiated by Richard Wagner, who suggested at the occasion of a visit of Wilhelm Heckel in 1879. Introduced in 1904, it is similar to the oboe but pitched an octave lower.
The heckelphone is a double reed instrument of the oboe family, but with a wider bore and hence a heavier and more penetrating tone. It is pitched an octave below the oboe and furnished with an additional semitone taking its range down to A. It was intended to provide a broad oboe-like sound in the middle register of the swollen orchestrations of the turn of the twentieth century. In the orchestral repertoire it is generally used as the bass of an oboe section incorporating the oboe and the cor anglais (English horn), filling the gap between the oboes and bassoons.
The heckelphone is approximately 1.3 m (4 ft 3 in) in length, and is quite heavy: it rests on the floor, supported by a short metal peg attached to the underside of its bulbous bell. An alternate second bell, called a "muting" bell, is also available, which serves to muffle the instrument for playing in a small ensemble. This arrangement is unique among double-reed instruments. It is played with a large double reed that more closely resembles a bassoon's than an oboe's reed.
Smaller piccolo- and terz-heckelphones were developed, pitched respectively in (high) F and E♭, but few were made, and they were less successful than the baritone-range instrument.
The first use of the heckelphone was in Richard Strauss's 1905 opera Salome. The instrument was subsequently employed in the same composer's Elektra, as well as An Alpine Symphony (though this part frequently calls for notes that are below the range of the heckelphone), Josephslegende and Festliches Präludium. It was adopted as part of the large orchestral palette of such works as Edgard Varèse's Amériques (1918–1921) and Arcana (1925–1927), and Carlos Chávez's Sinfonía de Antígona (1933). Aaron Copland's Short Symphony (Symphony No. 2, 1931–33) calls for a player to double on cor anglais and heckelphone, but a cor anglais may be used for the entire part if a heckelphone is unavailable...."