5 Knobs And 2 Toggles On A P/J Bass? Sure! (But Is Losing Passive Tone Control Worth It?)

Over the weekend our illustrious leader Max put this together:

…and this is what it used to look like:

Yes, it is completely functional, and yes there is now a battery box in the back where there wasn’t one before, but the point is this:

This totally dives into what you would call “heavy modification” territory.

The short version of the mod is this: A conversion from passive to active electronics.

The long version:

What you see in the first photo for knobs left-to-right are bass EQ, mid EQ, treble EQ, pickup blend, master volume with push/pull to switch between active and passive.

The two toggle switches are both 3-position. The one towards the back is a punch switch for low-mid frequencies, and the one under the pickup is a presence switch for mid-high frequencies.

Is there any passive tone control? No, there isn’t, because the preamp system installed doesn’t permit for it. Actually, that’s not true. You could make any preamp system without passive tone control have it, but not without some more (fairly serious) wiring modifications.

…and that brings up the point of modern preamps that include a passive tone control.

The first thing to know about passive tone control is that it’s not a new thing, and in fact is a very old thing. Some companies who sell preamps will list passive as a “vintage feature”. Yes, it is an old-school feature, but it’s not anything that’s new or groundbreaking by any stretch of the imagination.

The second thing to know is that preamp which does not include a way to include passive tone control can make it challenging to add one in.

Example, the finished cavity area with shielding:

Obviously, the above isn’t what you would call “pretty”, but then again there’s no real way to make it pretty when you have to deal with ribbon connectors. Lots of squashing around is going on, and bear in mind this was after the cavity was cut wide to accommodate it.

In other words, the above setup is literally as “clean” of an install as you can get it. When you’ve got a bulky preamp combined with a lot of wires and ribbon connectors on top of that, “limited space” takes on a whole new meaning. 🙂

Now bear in mind I’m not saying any of this to scare you off from performing mods like the above, but it’s good to know what you can potentially be dealing with concerning some preamps out there. Also know that not all preamps are the same. Some are bulkier than others, but it’s a safe assumption to make that you’ll have to do some squashing when you go to install it, no question.

The third thing to know about a setup like this is that your sound guy could potentially hate you for doing this. When you install a 3-band EQ and some punch/presence toggles with it, obviously you’re going to want to tweak your tone like crazy, because hey, why not, right?

While mods like this is something you’ll certainly appreciate, the sound guy won’t take it as you doing him a favor, and instead probably get royally ticked off at you constantly changing your sound around.

I’ll put it this way: If you’ve got a good working relationship with your sound guy, warn him in advance if you’re going to mod up a bass like the above; he’ll appreciate that much more than just springing it on him out of nowhere.

Is losing passive tone control worth it?

This ultimately depends on whether you feel you have a need for passive tone control or not.

Some players can easily live without passive tone control and don’t miss it at all once they install a 3 or 4-band EQ, as real-deal EQ can obviously give you much more tone-shaping control compare to passive.

Other players however do like having passive, either for having a “non-battery” tone control solution and/or because passive shapes tone in a way unique to what it is.

Fortunately, with modern preamp options, you have choice when it comes to this. If you gotta-gotta have the passive control along with the preamp, those are available. If you feel you can live without it and just go with the preamp EQ and alternatively use the master volume sweep (which can also act as a way to roll off the treble because of the nature of a 250k potentiometer), that’s fine too.

The details on the above bass mods

The bass is a Fender comprised of Asian-made woods (meaning it’s not a US model). Pick guard was custom cut to accommodate all the knobs and switches, and the output jack was moved to the side. Battery box was installed in the rear.

The preamp used was a Taurus TDM2, and the pickups are Lindy Fralin P/J set.

On a final note, no, the bass is not orange. It’s actually Fiesta Red. But under hot work lights it appears orange. 🙂