from passive tone control to active...

Jonki · #1 01-20-2004, 08:51 AM

I have a passive tone pot. on my bass now, by upgrading my passive tone control to active tone control, will this improve the sound on my bass?
I've got 3 pots. on my bass, 1 brigde pickup volume, 1 middle pickup volume and a tone control.
My pickups are some cheap single-coils.
here is a pic of the active tone control circuit.

thanks for all answers
best regards Jonki

Mottlefeeder · #2 01-20-2004, 10:35 AM

Putting treble and bass on a bass may well just duplicate the tone controls that you already have on your amp, unless you want to experiment with tone controls before and after a pedal.

The advantage of an active circuit is that it gives you a higher output signal, which may give you less noise, depending on what the pickups are picking up, and how much hiss your on-board preamp is producing.

Unless you are prepared to experiment to find the best frequencies for the tone controls to operate at, I would leave it alone. You can learn a lot of songs and techniques in the time it takes you to debug a small project.

pilotjones · #3 01-20-2004, 11:46 AM

Without getting into an argument here, there are several reasons you might want to try the project.

- Some people like passive basses. That's fine. But just as many like active. That's fine too.
- Having the tone controls on your bass lets you instantly adjust the tone.
- Doing a project like this can be a lot of fun, and you'll gain knowledge in the experience.
- - you can also build the preamp in a box, outside the bass, and install it onboard later if you like it.
- The higher output level is one advantage of an active circuit. The other is that it buffers the pickups from the instrument cable and the amp input, giving you a consistent tone regardless of amp input impedance and the capacitance of long or cheap cables.

Jonki · #4 01-20-2004, 01:26 PM

thanks for the answers

current electronics :
http://www.home.no/jonki/Bass/oldelectronics.jpg

schematics of the current electronics :
http://www.home.no/jonki/Bass/tonecontrol.jpg

schematics for the new electronics
http://www.home.no/jonki/Bass/activecontrol.jpg

if i shall install the new electronics, how shall i install it? for me its not a problem to make a pcb of the circuit, but the problem where i shall place it. Im also considering a low-pass filter to get rid of possible noise.That's not a problem to make a PCB of it either ;-)
best regards jonki

Mottlefeeder · #5 01-21-2004, 03:09 AM

I do not disagree with anything pilotjones says, but there are a couple of questions you need to consider before you start.

a) You talk about improving the sound of your bass, without saying what you dislike about the present sound. If you cannot get the sound that you want from your bass with your current amplifier's tone controls, are you going to make a big difference by putting in a second set of tone controls? You may be better off moving to different strings to get the sound you want, or moving to different pickups if you are lacking top end (if your pickup is not picking it up, you haven't got anything to amplify!).

b) Your circuit looks like a general purpose hifi type tone control, with +/- 15 volt supplies, which suggests that the treble will be set to amplify cymbal 'tizz' and the like. If so, you will need to reduce that frequency, because basses don't produce much signal that high up.

c) The circuit may clip (overload) when you run it at +/- 9 volts, with your pickups, so, are you going to be able to reduce the gain, or are you hoping for a 'plug it in and it works first time module'. If the latter, you might like to consider an off-the-shelf tone module, which will include volume and blend controls.

I spent many happy hours building electronic projects, and almost all of the audio ones ended up being replaced by bought equipment. Do it for the experience, - yes: do it for cheapness and quality, - doubtful.

Jonki · #6 01-21-2004, 08:50 AM

Im just want to do it for fun and gain some bass-electronic experience. The sound of my bass is kinda low-end, but my effectsprocessor does an alright job to thicken the sound. I'm considering a pickup set from EMG, but not now. I must do some research about changing pickups and how the diffirent pickups sound like. I have a Morgan 4 stringer and it's a cheap copy of a Fender Jazz Bass, I like the look of it and the comfort of it.
I'm also considering a new bridge, but that's not a 1.priority.

someone who has experience with these? http://www.emgpickups.com/displaypro...5&catalogid=60

luknfur · #7 01-25-2004, 03:28 AM

Some good input here. I've done my share of pup and electronic swaps. It is fun, and it is frustrating as well. But the only way that's even half feasible to really compare tone is to have the same bass with one variable swapped at a time. Even at that, you go tone deaf after a while. The point about playing bass instead of playing electronics is well taken, no sound will compensate for technique.

If you have access to other basses (music stores, friends, whatever), I'd find a bass with a sound you like and go for those electronics and strings. You'll get a lot closer to "your" sound and spend more time applying it. The construction of a different bass will alter it some but in my experience, if you get the same electronics, strings, and rig you're playing through, you'll be close enough.

Another option is to pick up a Korg PX4B (or whatever) and for the price you'll pay for pups and preamp, you'll have more "useful" sounds than you'd ever have time to jack with. You can carry it in your pocket and use it with any bass without having to alter the one you have.

Jonki · #8 01-25-2004, 11:54 AM

I already have a Korg PX4B and some thick strings
(Ernie Ball Hybrid strings). When I play G and D string, the sound is to light and thin, no matter what i change on my amp or my px4b. I am satisfied with my bass, except for the pickups. They are cheap and low-end. But i think the EMG J set will do the job to thicken the sound. Anyone who has input on this set?
best regards Jonki

luknfur · #9 01-25-2004, 04:13 PM

Pups are the heart of the electronics and you can't get something from nothing. No matter what electronics you're running, one issue you'll frequently encounter is getting all strings to get the tone you want. For me it's either the G string's too bright or the E strings too fat. I've got Bart, EMG, Aguilar, Duncan, Reflex, and Lightwave systems.

All these systems are good just different, it's just a matter of preference and style you play. Find a bass that has the sound you want, and get those electronics. But you either have to have room or make room for a battery (unless you run another jack for an external adapter like is on the Lightwave systems). The BTC, NTBT, or OBP1 units themselves occupy minimal space - but it's space you may have to create.

Jonki · #10 01-25-2004, 05:25 PM

I play mostly metal. But a jazz bass sound in metal are kinda cool for me

I just want to have something thicker sound on G and D string. Just believe me, my current pickups are bad and noisy sometimes. But as I said, I really like a jazz bass sound. I think the EMG pickups will suit my playing style