From the late 1960’s through the 1970’s, Swedish speaker manufacturer Sonab was famous for their unusual and wonderful sounding speakers which used upward firing woofers, and multiple tweeters. Designed by Stig Carlsson, the ‘Orthoacoustic’ series enjoyed a period of great reviews and major sales success. Stig employed simple drive units, a 165mm paper cone woofer and multiple cone tweeters in arrays that created a very wide listening area. A crucial factor was the position of speaker relative to the walls, creating a diffuse HF soundfield. OA speakers were unforgiving demanding corners, but those who could fit them in their room were rewarded with extraordinary performance. Stig had developed the original Orthoacoustic principle in the 50s. After his death in 1977, at age 77, Sonab began producing much more conventional and very boring speakers.

The supply of spare drivers has long since been depleted, but cones and voice coils are still available, along with crossover parts. When repairing Sonab OA speakers we recommend the dreadful 2-pin DIN connectors be replaced by binding posts, to allow them to be used with modern speaker cables. Lövånger Elektronik was a contract furniture manufacturer, building enclosures.

V1, small cubes, using a single Philips 216mm full-range driver. .

OA4, 2 way, 216mm LF facing upwards, tilted 15°, and a Peerless cone HF facing in same direction at 45° upwards. 8-ohms, 300x300x305mm.

OA4 Type 2, floor standing speaker, with 216mm LF driver. Baffle (top face of enclosure) is flat wood. 8-ohms, 400x400x225mm.

OA5, 2 way, 5 drivers. 216mm LF, and 4x Peerless HF. 8O.

OA6 type 1 & 2, Active bass 3-way system. 250mm LF underneath; 216mm as MF on flat top; and 4x HF units. XO at 250 & 2k5Hz. One of the first active systems. 100w amp with switches for 25~200Hz boost, and 200~600Hz boost. Powered the LF unit only. Internal layout of the amp is a complete dogs breakfast.

OD11, 2 way. 165mm LF. Aka: the Carlsson-cube, the smallest Sonab. Single HF unit. 8-ohms. Both drivers recessed and angled in an ABS baffle. Incl wall brackets and wall drilling template.

OA12, 2 way. 165mm LF. 2x HF. 18L enclosure, 7Kg, 35~18kHz, 88dB, 8O, 40w (DIN 45-573).

OA14, 2 way. 165mm LF. 4x HF. 35L enclosure, 11Kg, 25~18kHz, 88dB, 8O, 40w (DIN 45-573).

OA50, and OA50.2, 2-way. 20L enclosure tuned to 30Hz, 89dB, 8O. Peerless 165mm LF, paper cone. 25mm textile dome HF.

OA51, 2-way. 16L enclosure, tuned to 38Hz. 88dB, 8O. 177mm LF. 25mm textile dome HF.

OA52, OA52.2, and OA52.3, all 2-ways. Very unusual 20L enclosure, tuned to 30Hz. 89dB, 8O. 177mm LF. 25mm textile dome HF. System included a set of 4 thick foam pads for the walls.

OA116, 3 way, 1977. 45L, with an angled 165mm mid-bass, in a hat-box enclosure, 6x cone HF units, 3 in an arc facing the listener, and 3 facing other directions. Down-firing, ported, Enclosure had 3 internal (horizontal) shelves, presaging the B&W matrix wine-box. XO at 400Hz, 6dB/8ve & 1K8Hz, 12dB/8ve. With wheels, and jumper to set HF level. 260x460x670mm22Kg.

OA2212, 2x LF, 2x MF tilted 22° from upright, with a 15° angle between them, 8x HF units in an 70° arc, and 4 more in odd directions With wheels and jumper to set HF level. Supplied as L/R pairs. 300x550x750mm