Sadowsky SBP-2 V2 Bass Preamp (black)

That's exactly what it is: a preamp in a pedal. Jazz Bass icon Marcus Miller installed one in his bass, unfortunately ruining his nice pickguard. I would have expected better for my beautiful Fender MIJ, but I can't really do without this, as it significantly boosts and enhances the mid-range frequencies. If you have an active bass, you certainly don't need something like this. However, one more thing: to achieve maximum noise reduction, the volume must be turned up to the maximum, then, as with an active bass, reduce it by -10 dB, and the effect must remain on. A bigger problem could arise due to noise from the power supply, which requires a battery and screwdriver, which is exactly what I wanted to avoid with the use of a passive bass. And finally, always unplug the cable after playing, otherwise the battery will drain quickly. The device gives a very solid impression, but it is also somewhat rough in its construction and has a fiddly dampening screw for the compartment. Nevertheless, it's still great value for the price. There might be better options available.