Bass eq pedal

Hi all

I am looking at an active bass only pedal - a single knob pedal that boosts bass!
So instead of (for example) the Xotic RC Booster which has bass, treble and then the gain/volume - I want just the bass. Doe such pedals exist? Or is there a circuit that is available for a DIY build?

Many thanks in advance...
Glassmoon

 

Oh wow! That is exactly what I am after Many thanks @tom_ric