I think Richard's reference to the RFH and FTH instruments is specifically in the context of the difference between the way the Compton and Makin firms (not the individuals) exploited the technology available to them. Compton knew the desirability of multiple generators, generators with variant pitches, etc. as seen in those specials mentioned, which were actually quite early instruments presumably made under the direct control of LB, WF and JT. But that was as far as the commercial utilisation went. AFAIK no Electrones made at Acton had the additional generators that Richard describes to 'fill in the gaps'. In the later years, when one might have expected them to pull out all the stops to give the electrostatic system every chance of competing against its rivals, there seem to have been very few organs even with dual generators.
This ties in with Graham Dukes' point although the latter needs clarification. Graham might have been referring to the introduction of the 7-octave 2.5" generator into classical instruments in 1957. Until then, the standard off-the-shelf classical Electrone range (discounting diminutive instruments such as the 354) comprised only two models, the 347 and 348. Both of these used 5-inch external generators with integral harmonic content in their waveforms - see the EK pages for detailed descriptions http://www.electrokinetica.org/d8/3/index.php They had some significant shortcomings, greatest of which were perhaps the high background noise level and the 348's very limited tonal scope, however they were clearly intended to provide full-bandwidth harmonically rich sound within the system's practical limitations. In 1952, the 'Melotone' model 352 2m console organ was introduced, intended for light music only, using the 2.5" internal generator system. This was a return to the additive synthesis principle of the early experiments and the original cinema Melotone, but due to the small size of the generators the highest frequency available was B7, i.e. below 4kHz. Clearly, no-one at that point was under any illusion that this was capable of properly recreating pipe tones, regardless of the names on the stopkeys of the 352.
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