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The Column Eight was launched in 1958 - the first year that stereo records were generally available in the UK - and production continued through to 1961.
These substantial speaker units are made from quality veneered walnut wood topped by radiating covers, having a grill on each side. Apart from some minor scratches and slight fading on the lower edges in some places, these speakers are in really good condition externally. Internally, they are immaculate and I do not think they have ever been taken apart; please check all the photographs.
They were designed by the founder of Wharfedale, Gilbert A Briggs, and his precise hand-drawn diagram for these speaker units and enclosure appears in one of his books 'Loudspeakers' - this is included in the photographs for your interest.
Each Column Eight has a single 8" driver unit created especially for the Column Eight: the 8/145 model. The driver is mounted in the top of the main unit and faces upwards. The sound hit the outside of an inverted aluminium cone and is then radiated through 360 degrees. The upper speaker enclosure is lined with fibre glass 1" padding and it takes up about 2/3rds of the total volume area. At the bottom of this enclosure is a slatted acoustic filter which projects the lower frequencies downwards into the lower enclosure and then out through the slits situated on two sides of the column. In the photographs you can see a dowel that traverses the main upper enclosure at the half-way point. This is not to add strength to the construction but is used to control the resonant frequencies of the unit: it seems that each unit could be individually fine-tuned.
These Column Eights have a serial number stamped into the top panel by the speaker - one is #45 and the other is #58. One can estimate that with their low serial numbers both of these units were made not long after production started.
One column [58] has had four small holes drilled into the upper surface of the speaker enclosure - the speaker mounting panel. There is no evidence of wood shavings, other intrusions or modifications inside the cabinet so possibly this was a factory modification in the final 'tuning' phase of manufacture. This column also has what look like nickel slot-headed screws retaining this upper panel: all other screws in the main construction of both columns are cross-headed and made of copper. I am not aware of any difference in response or otherwise between either of these Column Eight.
The 8/145 driver is rated at 12/15 ohms and has '14,500 lines' [magnetic strength]. I would estimate that the power rating would be around 6 watts RMS [based on data from subsequent units derived from it]. It has a resonant frequency of 50Hz in free air and was designed as a wide range speaker; around 20 Hz - 20,000 kHz.
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