05-02-2023, 08:39 PM
The difficulty of reproducing bass was one of the early obstacles to recreating the sound of a pipe organ. Granted, the pipe organ needs big pipes to do that but once you have bitten the bullet, you get powerful fundamentals down to 32Hz, or if you are ambitious and add a 32 ft. stop, to 16Hz. Such frequencies were almost impossible to replicate at realistic SPLs with available amplifier powers and speaker designs during the early attempts at electronic tone generation, so even if the waveform could be produced faithfully, the acoustic result was weak and unconvincing to the audience.
Pics below show the giant 27 cu.ft. bass cabinets used by Compton with 18" drivers. Note the steel cross-bracing rods. The treble units were in separate enclosures. The whole system was bi-amped all the way through i.e. the bass generators fed the bass amplifiers fed the bass speakers, to avoid intermodulation. The amplifier chassis each had a bass and a treble channel, and the OPTX in the bass channel was twice the size of that in the treble to enable it to deliver full power at the bottom end.
They did include a 32 ft. pedal stop in the specification of many of their better church models, including the 347 to which these cabinets belong. It just-about works but it wouldn't fool anyone that they were listening to a pipe organ. If space constraints dictated smaller cabinets, e.g. the freestanding types often located in the chancel, the 32 ft wasn't really usable. My hunch was that the stop was included primarily for specsmanship, not for musical performance.
Pics below show the giant 27 cu.ft. bass cabinets used by Compton with 18" drivers. Note the steel cross-bracing rods. The treble units were in separate enclosures. The whole system was bi-amped all the way through i.e. the bass generators fed the bass amplifiers fed the bass speakers, to avoid intermodulation. The amplifier chassis each had a bass and a treble channel, and the OPTX in the bass channel was twice the size of that in the treble to enable it to deliver full power at the bottom end.
They did include a 32 ft. pedal stop in the specification of many of their better church models, including the 347 to which these cabinets belong. It just-about works but it wouldn't fool anyone that they were listening to a pipe organ. If space constraints dictated smaller cabinets, e.g. the freestanding types often located in the chancel, the 32 ft wasn't really usable. My hunch was that the stop was included primarily for specsmanship, not for musical performance.
