Master volume and pasive tone, before or after the preamp?

Discussion in 'Pickups & Electronics [BG]' started by Evilheim, Apr 24, 2021.

  1. Evilheim


    Dec 27, 2017
    Madrid, Spain
    Hi everyone!

    A few weeks ago I started a project about rewiring completely my Fender Jaguar Bass, as it happens some times, I ended up trying to make everything as clean, good and electronically efficient as I can, being that one of the goals of the project so I can learn more about electronics (I'm still a noob).

    So the plan is to run two EMG-JX active pickups with a 2-band TWB2 Baz on-board preamp both with 18v power, and came to my mind the question about where it would be more efficient and desirable to put the master volume and passive tone control, electrically and signal-whise, before or after the preamp? But I coun't find any solid answer.

    I've read a couple of threads about this subject (this, and this) but knowing that EMGs are low-Z and already buffered pickups, and having the volume and tone after the preamp, it's still any risk of the volume pot starting to load the impedance of the signal? Also with that same configuration, is there any way or possibility to put a bypass switch on the preamp? so I also have the option of sending the pickups signal directly to the master volume and tone and then to the output jack.

    With my limited knowledge about the subject I've been thinking that the most efficient signal flow would be:

    EMG-JX pickups >
    Pick-ups on/off switches >
    Pick-ups parallel/series switch >
    TWB2 Baz Preamp >
    Master Volume and Tone >
    Output Jack.

    I'll be using 25K potentiometers for the volume (Log) and tone (Lin), and 100K (Lin) for the bass and treble controls as sugested by the preamp builder. (EMG works with 25k pots tho).

    I've been reading also that the parallel/series won't work with active pickups, but in my case, it works, I have the EMGs with all those switches and works fine.

    So, sorry for such a long text for this simple subject and thank you very much before hand to take your time reading and answering it!
    Last edited: Apr 24, 2021