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Single Speed Leslie Conversions
EIS converts older Leslie speaker models, such as the 31 and 22 series, to multi-speed operation. The 31 H in this photo was converted to 3 speed (fast, slow, off) with new motors and a TREK II relay. Motors are typically mounted in box enclosures similar to factory 2 speed cabinets. Due to lack of availability of 2 speed motor stacks, EIS prefers that customers provide their own. EIS can attempt to source these as well, and can restore worn or damaged motors for this purpose.

Custom Bi-amped Leslie
EIS can reconfigure your Leslie with higher powered amplification, greatly increasing speaker output. With this bi-amplified system, the original 40 watt tube amplifier is retained to power a heavy duty treble driver, providing the crunch and warmth most players prefer. The bottom end is powered by a 200 watt or greater solid state amplifier, matched to a high performance bass driver. A custom EIS active crossover provides the same crossover point and slope as the passive device in the original Leslie. When you crank this Leslie, "the trees duck"! Price depends on the speaker components and bass amplifier you select.

Leslie Amp Rebuilding and Conversion
EIS rebuilds amplifiers for all Leslie speaker models. Conversion from one model to another (e.g. 147 to 122) is offered as part of this service. Our rebuilds are not a "cut and paste" operation. All wiring is meticulously removed before new components are soldered in place. EIS has also developed a new wiring arrangement for 122/147 amps that simplifies the layout and reduces noise. The chassis is repainted and new labels are added as required. We recommend addition of the TREK II relay during any rebuild. These amps are rebuilt to perform, last...and look better than the orginal!