In the Georgian Era (18th century) sounds consisted of metal rods about 9 inches (22 centimetres) long, composed of brass or bronze, inserted into the male urethra. This was then vibrated using a tuning fork. The resulting vibration was influenced by many factors such as the metal used, the length of the rod, the diameter of the rod, the depth of insertion and the frequency of the tuning fork.
This was the era of Chamber music or ‘Baroque & Roll’ as I call it, so tuning forks were easily obtained. Brothels, such as those featured in the BBC drama ‘Harlots’, offered this service because it was very quick – works in about 90 seconds – with no need to disrobe, no risk of catching a disease and can be repeated again after less than 5 minutes (and again!)