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Vacuum Tube Combo Preamp

The best sounding Combo Preamp for Leslie Speakers available!

Unlike other combo preamps on the market which use sterile sounding solid-state transistors/opamps, our preamp is 100% class A vacuum tube. There are two tubes inside, a 12ax7 and 12au7,  and a quality American made output transformer..... similar to the AO28 preamp found in a classic Hammond B3. True vintage tone!

It also has bass and treble controls, for complete control of the sound. These EQ knobs are designed to give a flat frequency response when in the middle position, and you can cut or boost from there.

This preamp has LOADS of gain, while also having high headroom. It will provide beautiful clean, warm tones to your Leslie. It also has the capability to heavily saturate your Leslie if overdrive is your desire. There is lots of flexibility of tones - at various volume levels - simply by adjusting the controls on the preamp and the volume control on the Leslie amp.

Any type of Leslie output(s) can be installed (up to 3 max): 122, 147, 251, 9-pin, or 11-pin. All Leslie outputs can be used simultaneously.

It also has 1/4" unbalanced (TS) and balanced (TRS) outputs, so it can be used as a tube preamp for any audio source. Use it as preamp/DI for bass or guitar, or use in the studio to warm up a track, etc... the possibilities are endless!

Has two 1/4" unbalanced inputs: hi gain and low gain.

This works great for any instrument or audio signal - guitars, clonewheels, keyboards, synthesizers, re-amping a recorded track, etc!

A stop switch for the Leslie can be added by special request, contact us for more info.

Available in 120v or 230/240v.

These are built to order, lead time 4-6 weeks.


Hi Input: 1M input impedance, ~60db of clean gain

Lo Input: 80k input impedance, ~52db of clean gain

1/4" Balanced TRS output: 500 ohm output impedance, 30 Vrms max output

1/4" Unbalanced TS output: 125 ohm output impedance, 15 Vrms max output

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