The design, construction and testing of a three way loudspeaker system using commercially available components

by B. J. Appleby

Institution: Central Queensland University
Year: 0
Keywords: Loudspeaker cabinets Design and construction.; Loudspeaker cabinets Testing.; Loudspeakers Testing.; Thesis. Final Year Project (Applied Physics)
Record ID: 1059299
Full text PDF: http://hdl.cqu.edu.au/10018/937588


At the present time there are available several complete three-way speaker systems in kit form which include the speakers, crossover networks and enclosures. These are usually of the closed-box type. Also available separately are the various types of speakers and crossover networks, which can be installed into a loudspeaker enclosure designed by the individual. There is ample literature including texts, pamphlets and small booklets which outline how such enclosures may be constructed. Presently the majority of this literature is directed towards closed-box enclosures. The two alternatives above are attractive as the cost of such systems is appreciably less than the cost of completely assembled systems. This project involved a design f o r a vented-box enclosure which employed three speakers and a cross-over network that were obtained 'off the shelf' from a local retailer. The practical approach adopted for the development of the system, the measurement of the performance of the system, the validity or otherwise of manufacturers specifications of the components, the reliability of the specifications outlined in the literature are investigated in this project for a vented-box enclosure. The performance of the loudspeaker system proved t o be satisfactory, notably for frequencies greater than 200 Hz. For the frequency range 50 Hz t o 20 kHz the output, when having a constant current of 0.5 amp (2 watt electrical power), was 7 7 -+ 6 dB except in the range 70 Hz to 160 Hz where approximately a 10 dB drop resulted due to inadequate perforrnance of this particular base speaker in this frequency range.