The Hammond A-100 organ is identical to the famous Hammond B-3 except its speaker and reverberation systems are built into the organ console. It has two 61-note manuals and 25 pedals with the standard drawbar sets, presets, Selective Vibrato and percussion. In addition, there are three 12-inch speakers and a reverberation dial. This instrument was promoted as a home organ and also worked well in music teaching studios as it was completely self contained. Additional tone cabinets could be added, if needed.
The HammondFaq has a 
number of pictures of the internals of an A-100.
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