Page 19 Advertisement 2

New Zealand Listener, Volume 14, Issue 353, 29 March 1946, Page 19

3OSOSOSOS0 OSOSOCOSOCOC0S0S0S0S0C0S30= COL UMBUS International MODEL 90 DOCOSOCOSOC08080S SOCOCOCOS0SOS0S0= Loudspeaker Design a net Columbus development of unsurpassed tonal excellence HE function of a loudspeaker is to reproduce, in T audible form, the electrical impulses which are received from the aerial and converted by the radio receiver into impulses of "audio frequency. 9} In the first place, the tonal quality of the radio depends upon the "purity of the audio frequencies that are pro- duced by the receiver itself; but the ability of the loud- speaker to convert those impulses into audible tones of natural fidelity is obviously of highest importance. We have described elsewhere how, from a design arrange- ment known as discriminatory tone control, Model 90 derives audio characteristics that surpass anything attained by the conventional radio receiver. In other words, the audio frequencies produced by Model 90 are of such a nature that, given ar efficient design of loudspeaker, high tonal fidelity of the radio is assured: So Columbus has been concerned to provide with Model 90 a loudspeaker of extremely high sensitivity. This has been achieved by close attention to the methods and materials used in the construction of the moving parts of the speaker, with the object of imparting maximum flexibility to the loudspeaker diaphragm without interfer- ing with its sturdiness and reducing the weight of the moving parts without loss of durability. Further to this, Columbus has fitted to its Model 90 loudspeaker a design of "output" transformer which adds greatly to its effective bass response and considerably enhances depth of tone in the reproduction of music. Nation-ide Service These characteristics, coupled with its massive propor- tions, bring the Model 90 loudspeaker to new levels of reproduction efficiency, making it indeed worthy of the Whangarei, Auckland, Hamilton, Rotorua, splendid radio of which it is a component part. Gisborne, Napier, Hastings, Dannevirke, Taihape, New Plymouth, Wanganui, Palm erston North; Masterton, Wellington, COLUMBUS Nelson, Greymouth; Christchurch, Timaru, Oamaru, Dunedin, Gore, Invercargill RAD / 0 International COLUMBUS Model 90 the best modern radio receiver in the world.