Hornbostel-Sachs - Application of The System

Application of The System

Beyond the top three groups are several further levels of classification, so that the xylophone, for example, is in the group labeled 111.212 (periods are usually added after every third digit to make long numbers easier to read). A long classification number does not necessarily indicate the instrument is a complicated one. The bugle for instance, has the classification number 423.121.22, even though it is generally regarded as a relatively simple instrument (it is basically a bent conical tube which you blow down like a trumpet, but it does not have valves or finger-holes). The numbers in the bugle's classification indicate the following:

• 4 – an aerophone
• 42 – the vibrating air is enclosed within the instrument
• 423 – the player's lips cause the air to vibrate directly (as opposed to an instrument with a reed like a clarinet, or an edge-blown instrument, like a flute)
• 423.1 – the player's lips are the only means of changing the instrument's pitch (that is, there are no valves as on a bugle)
• 423.12 – the instrument is tubular, rather than being a conch-type instrument
• 423.121 – the player blows into the end of the tube, as opposed to the side of the tube
• 423.121.2 – the tube is bent or folded, as opposed to straight
• 423.121.22 – the instrument has a mouthpiece

423.121.22 does not uniquely identify the bugle, but rather identifies the bugle as a certain kind of instrument which has much in common with other instruments in the same class. Another instrument classified as 423.121.22 is the bronze lur, an instrument dating back to the Bronze Age.