there were countless trumpeters and horn blowers and since the whole army was shouting its war cries at the same time there was such a confused sound that the noise seemed to come not only from the trumpeters and the soldiers but also from the countryside which was joining in the echo (Polybius 206–126 BCE).
In 2004, archaeologists discovered over 500 iron and bronze items in a small 30cm-deep pit in Tintignac, in France’s Corrèze region. These fragments were all that remained of objects intended as sacrificial donations to the cthonic deities, objects that were deliberately destroyed as part of the ritual donation. Some of the fragments, about 40 fragments, were identified as being parts of a carnyx, a horn used in Celtic warfare, and likely, rituals and ceremonies.
An archaeologist at Inrap (Institut National de Recherches Archéologiques Préventives) Christophe Maniquet wanted to know what a carynx sounded like. Maniquet collaborated with Joël Gilbert, a brass instruments specialist and other experts from an acoustics laboratory at the Maine-CNRS University in Le Mans in order to create a replica of the carynx.
You can read more in “Send for the bard!” from The Guardian.