The design ideas are the same as the ones behind Sonab OA-6. This speaker is however intended for high quality sound reproduction in larger rooms. The speaker uses the same bottom part as OA-6 but it is equipped with midrange drivers and tweeters on booth sides of the speaker, placed exactly as the ones on the topside.
It uses built in frequency corrected amplifiers, this indicates that this is a model similar to the OA-6 Typ 1 (Mk I).
Measures, taken from Sonab OA-6 Typ 1 (Mk I)
Box volume: 45 litres
Measures W x H x D: 29 X 77 X 51 cm
Principle: Bass reflex (two tubes). Omni directional. Each speaker has built in poweramplifiers, one channel for 25-250 Hz and channel for 250 - 16000 Hz.
Drive units, estimated
Woofer: 1pc. 25 cm 800 ohms woofer from "Svenska Högtalarfabriken" (Swdish brand later known as Sinus).
Midranges: 3 pcs 22 cm 800 ohms Philips 9710 full range units, in their own cavities. I do not know how the amplifiers were supposed to drive the mid- and high range, the OTL amplifiers used in OA-6 were designed for 800 ohyms load. Perhaps a series-paralell connection of the speakers were intended or perhaps the use of separate amps for left-, right- and upwards facing speakers.
Tweeters: 12 pcs. 8 ohms Peerless MT 20 HFC, facing lef, right and up.
Crossovers
Cross over frequencies: Proberbly 200 and 2700 Hz
Martin Dellstig - Co-Editor
This page was last edited 2006-07-22 20:16:11 by Jonathan
