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		Front Horn Front-loaded horns are designed to load the front of a compression or cone driver. Horn size depends on the frequencies it is designed for. Mid range and tweeter horns are small, bass horns are large or huge. Because horns have a limited bandwidth, they cannot do a "full" frequency range. You can use a front horn to load a full range driver at its lower frequencies, making the unit wider range than just direct radiation alone would allow. Then you can fit a crossover and a subwoofer or bass system to fill in the bottom octaves. This approach is taken by the Oris horn. Some examples of front loaded horns using full-range drivers: Bert Doppenberg's front loaded square horn. Another square horn with Lowthers. Bert Doppenberg's Oris 150 round front horn. VALVE Magazine Vol 6 No 4 has an article on a square front horn using Radio Shack and Diatone drivers. VALVE is published by Bottlehead.com. Bert's Oris horn is loaded all the way down to 150 Hz. This gives a nearly-full-range speaker from one radiating source. For lower frequencies, a subwoofer or bass horn is necessary. The front horn described in Valve Magazine Vol 6 No 3 is similar. Both horns are somewhere between 50 or 80 cm in diameter. An interesting 80 Hz front horn that is almost round is described by Richard Vance. This uses multiple strips in construction, see a picture of it here. Top