ETS Sound, Lighting, AV. - ETS Lighting, Sound AV Since 1996, ETS has grown to become one of the East of England’s leading professional Sound & lighting providers. Based in Wymondham (Norfolk), we are within easy reach of Norwich and the major trunk Since 1996, ETS has grown to become one of the East of England’s leading professional Sound & lighting providers. Based in Wymondham (Norfolk), we are within easy reach of Norwich and the major trunk roads and ideally located to serve East Anglia, the South East and the Midlands.