Reception of the commander-in-chief of the Bulgarian army in Tsarigrad (Istanbul), 1917.
The Janissary band is known in the West largely through the vogue it enjoyed in the classical era of WAM (“Typical!”). But I was curious to learn a little about its changing fortunes under Ottoman rule.
Within the military, the Janissaries were the standing army of the Sultan.  In the mid-17th century the explorer Evliya Çelebi, whose parents were attached to the Ottoman court, gave a good description of the mehter musicians at the time:
There are 300 artists in mehterhane-i Hümayun (the mehterhane of the palace) in Istanbul. These are quite precious and well-paid people. There is additionally a mehter takımı of 40 people in Yedikule since there is a citadel. They are on duty three times a day, in other words they give three concerts, so that the public listens to Turkish military music. This is a law of Fatih. Moreover, there are 1,000 mehter artists in addition to them in Istanbul. Their bands are in Eyüp S, Kasımpaşa (kapdan-ı Deryalık, the centre of the Turkish Naval Forces), Galata, Tophane, Rumelihisarı, Beykoz, Anadoluhisarı, Üsküdar and Kız Kulesi. These mehter bands are on duty (i.e. give concerts) twice a day, at daybreak and the sunset hour.
Mehterhâne, miniature from 1720.
In successive revolts through the 18th and early 19th centuries the Janissaries struggled to maintain their privilege and power. In Osman’s dream, definitive tome on Ottoman history, Caroline Finkel documents their changing fortunes: the end of their domination after the 1651 revolt; resistance to modernisation in the 18th century; the 1807 rebellion against Selim III, until growing ill-discipline led to their elimination in the “Auspicious Incident” of 1826. 
The instrumentation of the mehter military band included kös and davul large drums, zurna shawms, naffir or boru natural trumpets, çevgan bells, zil cymbals, and (borrowed from Europe) triangle. In the classic format, davul, zurna, and trumpets were each played by nine musicians.
After the “Auspicious Incident”, in 1828 it was replaced by a European-style military band, among whose directors was Giuseppe Donizetti (1788–1856), older brother of the composer. I wonder what happened to all those zurna players—this is just the kind of dispersal from court to folk that Chinese scholars observe for the late imperial period (I can’t quite deduce from the sources I’ve seen, but I surmise that such bands performed not just in Istanbul but for regional Janissary divisions).
As the Ottoman empire crumbled, from 1911 the earlier tradition was revived, but with its function more symbolic than practical, the band was again abolished in 1935. Whereas the new recording industry was just beginning to pay attention to the popular songs of the demi-monde, the mehter style was never going to be a commercial proposition. Still, one might suppose keen ethnographers would have documented it, as they were already doing elsewhere; I’ve been hoping to find some recordings from this period, but so far my enquiries have been in vain.
In 1952, leading up to the celebrations for the 500th anniversary of the conquest of Constaninople, the mehter band was resuscitated under the auspices of the Istanbul Military Museum, and in 1953 a unit was created within the Turkish Armed Forces.
Call Me Old-Fashioned (the traditional style was abolished in 1826!), but I still hanker after the “original” sound—here are a couple of recent recreations:
Of course, the zurna-davul combo, in smaller scale, has never disappeared from either urban or rural Turkey—as in China, where shawm-and-percussion bands also served the imperial courts and armies,
* * *
Returning to the classical era of WAM: you’d hardly know it, but that’s the kind of style, part of a wider fashion for Turquerie, that filtered down to Mozart and Beethoven before 1826, just as the Janissaries were in severe decline (see Eve R. Meyer, “Turquerie and eighteenth-century music”, Eighteenth-century studies 7.4, 1974). Vienna was a major forum for the East-West encounter.
One intriguing experiment was the Janissary pedal on the piano: 
And even if it’s not quite “authentic”, I like this:
With thanks to Caroline Finkel.