Roland Collaro supplied photographs of his custom made speakers which conformed completely to the design outlined in A.R. Bailey's paper, 'The Transmission-line Loudspeaker Enclosure', which was published in Wireless world in May 1972. the drive units are: B139, B110, T27 and the crossover the DN12.

Rolland recalls:

'I remember making the treck to a HiFi shop in Walthamstow Central to purchase the components back in the early 70’s. We had the enclosures built back in Sydney at the time by a friend who operated a speaker enclosures factory. If I remember correctly there were around 8 to 10 pairs made. I do not know how many still exist as I have lost track of the people involved. The sound from the enclosures is terrific and delivers on the articles claims at the low end, whilst delivering the clarity and depth the speakers are renowned for. My enclosures are currently connected to a Musical Fidelity A3.2 Integrated Amplifier with the combination delivering very good results.