Subcontrabass tuba
| Riesentuba in 36′ B♭, Markneukirchen Music Museum | |
| Brass instrument | |
|---|---|
| Classification | |
| Hornbostel–Sachs classification | 423.231 (Valved labrosone with wide conical bore) | 
| Related instruments | |
| Musicians | |
| Gerard Hoffnung | |
| Builders | |
| Historical: 
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The subcontrabass tuba is a rare instrument of the tuba family built an octave or more below the modern contrabass tuba. Only a very small number of these large novelty instruments have ever been built. Most are pitched in thirty-six-foot (36′) BBB♭ an octave lower than the BB♭ contrabass tuba, their fundamental note B♭-1 corresponding to a frequency of 15 Hz – such a slow vibration that it can scarcely be perceived as a note.