The two families
122 — balanced (6H hookup). The classic Hammond pairing. A balanced input rejects AC hum and introduces the famous gentle delay between flipping the speed switch and the rotor changing speed. 41" tall, 40 W tube amp in the original.
147 — unbalanced (6W hookup). The “universal” version, designed to hang off organs with their own amplifier and speakers — A-100s, Wurlitzers, and everything inside your living room that already makes sound. Speed switching uses a separate AC signal: simpler wiring, cheaper kits, but more sensitive to mains hum and no speed-change delay.
Same idea, different sizes: 142/145 are the 122/147 in a 33" cabinet, 222/242 are 27" low-boys, 251/351 are two-channel 6C cabinets, the Pro-Line solid-state series (760/770/900/910/925) uses a 9-pin hookup, and modern reissues (122A, 147A, 3300) are 11-pin. The 122A is still sold new — $3,695 as observed in October 2026.
“Any Leslie can be hooked to any organ”
That line from the Captain Foldback kit lists is the whole truth of Leslie shopping. The cabinet does not care what it is plugged into as long as the kit reconciles the interfaces. That is why a $250 Leslie with no kit can be a worse deal than a $600 one with the right box:
- 6122 — 6H to older Hammond consoles ($500, Oct 2026, BB Organ).
- 6147 — 6W hookup ($457); 1147 — 6W to 11-pin ($467).
- 7271 — M / M-100 / L-100 spinets; 7272 — E-100/K-100; 7274 — T-series.
- 7275 — Wurlitzer and Gulbransen; 7278 — Lowrey; 7495 — Kimball.
- 7266 / 7962 / 7966 / 7967 — Yamaha Electone; 7971 — Kawai; 7075 / 7091 — Baldwin; 7130 / 7140 — Conn; 7144 / 7160 — Thomas. (Leslie’s own documentation repeats kit number 7960 for both Thomas and Yamaha — a known source error.)
Before you buy: five traps
- Early “30”-series cabinets with serials below 5200 cannot be driven by 6H hookup without an amplifier upgrade.
- 112 / 114 / 100GK (Gulbransen-era), 55C (Conn), 830 (Cordovox), 520 (no rotors) and 120C are the cabinets collectors flag as “be careful”.
- Passive spinet Leslies wire directly to pins 1 and 6 — no kit, but also no amplifier: they need the organ to drive them.
- A used 122/147 cabinet alone trades at $2,000–5,000; a broken one usually means a $1,249 factory-style replacement amp decision.
- The kit is part of the deal math, not an afterthought — check the organ×cabinet table before negotiating.
So which one?
With a tonewheel console (B-3, C-3, A-100 via kit), the 122 family gives you the cleanest, most “record” sound. With any organ that already amplifies itself, the 147 family is simpler and cheaper to connect. Both are correct; the wrong one is the cabinet whose kit you cannot find.