800BM; inspired on the GK800RB amplifier, served as a Back/Rear Mount option.

Make it growl, make it deep, make it clear. It’s all there!!

(!!Knobs Sold separately!!)

Active controls:

-Stacked Bass/Treble

-Stacked Hi-mid/Lo-mid

-Contour switch


Voltage: 9 to 27VDC  Current Draw: +- 3mAh (9v)

All our preamps are solderless

Instructions Manual


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The 800BM preamp borrows the EQ section of the famous GK800RB amplifier and squeezes it into an onboard preamp, this time with a Contour switch for an increase in sound options.

This tone stack has some serious high-frequency power and a very deep bottom end, just like the amplifier it’s based on, allowing you to explore different tones directly from your instrument.

The Hi-mid and Treble controls are highly interactive; the same goes for the Lo-Mid and Bass controls and the overall sound is always very “cut through” and clear sounding.

This preamps consists only of the Active components. This gives the user the chance to wire the passive elements (Volume, Tone, switches, etc.) to his preference.

For a full version of the 800BM, check the 800BMF.

Treble: Boost and cut around 4khz

Hi- Mid: Boost and cut at around 1khz

Bass: Boost and cut at around 60Hz

Lo- Mid: Boost and cut at around 250Hz

Contour switch: EQ pre-shape (V)

Warranty and Conditions

Any of our products will be replaced / fixed and all expenses will be covered once it has been verified that the problem isn’t a result of bad handling or negligence on the owner’s part.

If the damage is due to negligence or wrong handling, the warranty is lost and a cost can occur for the devices repair (the shipping costs will not be covered in such cases).

Let's talk about your next piece of gear

Before committing, it is important that you let us know about your instrument’s specs (electronics / number of controls, etc.), as well as where you are writing from. Give us a shout and we will get back to you.