The Hammond organ is one of the most underestimated instruments for pop and rock. There is a reason why it has been around for almost a century now, as it has an unmistakable sound that can be heard in countless pieces of iconic music. From the classic Hammond B3 or C3 to the A100 series tonewheel organ, the Hammond organ covers a wide range of sounds that can be used in many genres. It’s a unique electro-mechanic instrument that produces a warm and organic tone, making it well-suited for pop and rock. The Hammond organ was popularized by artists such as Jimmy Smith, Stevie Wonder, Jackie Wilson, and The Doors. This instrument also opened up new possibilities for jazz musicians, as it enabled them to perform in clubs without needing to hire an entire band. Even today, many modern bands still use the Hammond organ in their songs, helping to create a unique sound. The Hammond organ is an incredibly versatile instrument that can be used to create various sounds and tones. Whether you’re looking for a classic vintage sound or something more modern, the Hammond organ is capable of providing both. Its ability to blend tones makes it ideal for recording and layering complex sounds, allowing producers to create something truly unique.

Here’s a nice overview of the Hammond A-100 components, viewed from the back of the organ.

Schematic of Hammond Preamp AO-28

AO-28 Capacitors

AO-28 Resistors

* These components are for AO-28-1 amplifiers with no code letter only
** These components are for H-AO-28-5 amplifiers

Here’s some pictures I took of my Leslie 122 RV. From what I could find on  this model I understand that they usually come with a Leslie-designed reverb amp which is not deemed all that desirable, but this one actually has a Hammond AO-44-1 reverb amp in it, the very same as is found in the A-100 series. I think it sounds great, even through the small speaker that is mounted on the side of the cabinet.

Hammond Documentary by the BBC featuring Keith Emerson, Steve Winwood and Jimmy Smith