Model 104 was an 8 inch two-way system with an passive radiator augmenting the low frequency response, a format that was developed previously for the Cadenza system. The B200 bextrene coned bass driver for the 104 had a short coil/long gap magnet system for low distortion and the system included a three position acoustic contour control, which allowed +/-2dB of midrange level adjustment.

In 1976 the system was updated into the 104aB, where aB was an abbreviation for ‘acoustic butterworth’, relating to the shape of the acoustic response of the midrange and treble drivers in the crossover region. Perfect integration of the units will only happen if the acoustic responses of the two units conform to a precise characteristic. Previously, crossover filters had been designed primarily on the basis of the electrical response of the filter but, in reality, the acoustic roll-off is also a function of the natural roll-off of the driver response. By considering the filter and driver as a combined system the filter response can then be optimised to give the precise acoustic roll-off necessary for perfect integration.