Acrylic ear moulds were the original custom ear monitors developed by Garwood back in 1990 which remain ever-popular today. They were designed to couple with Sony Walkman-style drivers to produce a great-sounding and inexpensive ear monitor. The challenge in adapting the design for the Sennheiser drivers lay in their radically different shape, particularly the sound exit tube. A certain amount of head scratching is normal in such circumstances, and after due process it magically produced a couple of new engineering techniques. The drivers were in the moulds - now how would they sound? The position of the drivers in relation to the ear canal is crucial to how the ear monitor will sound. It's usually the bass response that is affected if the position of the drivers is wrong. Not so with the IE3s, however, which sounded fine in the moulds, apart from lacking a little sparkle. So out they came for further modification of the exit tube to avoid the absorption of high-end that was occurring.
(Ruth Rossington)
