Fender Active Circuit / Passive vs. Active / EQ questions

Discussion in 'Pickups & Electronics [BG]' started by dhclark76, May 28, 2005.

  1. dhclark76


    Mar 26, 2005
    Warning: I have a lot of questions, so if you have time, take a crack at all of them, or just pick one. I've already done searches on a lot of this, by the way, but I want to group these questions together so that you all have proper context.

    I've been playing for a while now, but I'm a total newb to understanding the technology of my instrument. When I bought my bass, all I knew is that I liked the look, sound, and feel of the instrument (unfortunately in that order). I didn't understand the whole passive vs. active thing but I knew that it had an onboard eq powered by a single 9v battery, which I recently had to change for the first time. This provoked a lot of questions. So here goes.

    Question #1: what kind of circuit do I have?

    The bass is a no name jazz composed of fender and warmoth parts. It has jazz pups and the technology is obviously a Fender circuit of some sort as it has the Fender brand label on it. But beyond that, I'm lost. Now that I'm playing consistently (which I wasn't for the last 3 years). I don't like the idea of having to change a battery frequently as this requires removing the back panel (6 screws), so I'm debating a switch to a passive system.

    Question #2: what are the pros and cons of a passive vs. active system, in this case? Should I just go passive, or leave it alone?

    Question #3: when playing an hour a day, how long should I expect the battery to last? (this a major part of question #2)

    Question #4: What EQ do I rely on? (read below)

    I'm also kind of confused by what EQ I should be relying on. Between the EQ on my bass and my amp (MAG 300), I'm never sure which EQ is the best to fiddle with. I'm trying to learn more about EQ, but I have a lot of reading to do on the subject and a lot of the process seems to involve training my ear. I cringe at the thought of getting a San Amp because it would just be one more EQ to have to worry about, but I will probably a good DI box eventually.

    Any info would be good. And if have any questions, or if you need pics, I'll respond as quickly as I can.

    Thanks :)
  2. A1, open the back and see if its fender branded, play with the controls and see what happens, it might be active pickups and passive controls or vice versa or both active

    A2, active is a bit louder and the signal can carry better along longer cables, sound-wise, its all in the eye of the beholder i find

    A3, the last battery i had in my bass, i played about 2 hours a day and it lasted 9 months, one of my other basses uses 2 9v batteries, it all depends on the circuitry and how much its being used

    A4, Play around with whatever sounds best to you, i find you usually have more control on an amp, and tweak only a little bit on the bass, with my sansamp i tweaked the EQ on it only to get the different overdrive sounds
  3. dhclark76


    Mar 26, 2005
    you've prompted a couple more questions now.

    (Although, first let me say thanks for responding.)

    I had no idea that the electronic system could be split up like you have explained. So let me try to break my replies down according to the order of your responses.

    The EQ circuit board is definitely Fender (the trademark is on the board). But now you've opened a can of worms as I have no idea whether it's the pups that are active, or the controls, or both. I don't even know how to begin to figure that out. I am fairly certain that the controls are at least active. Unfortunately, my knobs aren't set up in line like a traditional jazz. There's one volume knob and then one stacked knob that seems to be a bass control (on bottom) and treble (on top), and then there's a third knob that I believe is the mids. This is one reason that I'm trying to figure out if anyone is familiar with which Fender circuit I have, because simply I don't know enough about wiring to decipher how its hooked up simply by looking at the wires.

    If the EQ controls are active and the pups aren't, would the signal going to the amp be more passive or active. When I run to my MAG I usually plug into the high sensitivity input, however I usually have to crank things up pretty darn high before the VU meter responds at all. Whereas when I plug into the low sensitivity input, the VU needle responds with my input turned about half way up if I'm really cranking out the lows.

    Well that's not too bad as far as batteries go. Again, maybe if I can figure out which Fender circuit this is, someone with the same circuit can give me their experience with battery life.

    This is pretty much what I do now, but there's gotta be some better rhyme or reason to this. Does anyone else have a technique they use (i.e. leave the bass flat and EQ at amp, or visa versa) and a solid reasoning for it?

    Wow! I know this is a lot of reading, but thanks for taking the time.

  4. If it has controls for more than just tone (which is a treble roll off) its an active Pre

    If there is a battery in there at all its classed as active, cus the signal is stronger from active pickups and passive pickups are boosted by an active Pre

    One thing about batteries, always use good ones and keep a spare!

    I have everything flat and just turn each part til it sounds right to my ears, i find its easiest to get someone else to play the bass, and you toy about with the amp, then you play it yourself and make minor ajustments to suit that sound to your playing, i personally like to boost the mids and cut the bass n treble, however with my sansamp i think it sounds better with the bass and treble boosted a little (and it scoops/cuts the mid itself)

    Hope this helps :)
  5. David Wilson

    David Wilson Administrator Staff Member Administrator Supporting Member

    Oct 14, 2002
    Lower Westchester, NY
    There are a bunch of different fender circuits. So, you have three knobs, correct? One is a master volume I'm guessing - you can confirm this if it doesn't have a center detent (click).
    If the other two have detents, then I'm guessing the non-stacked one is blend and the stacked one is bass / treble.

    As to whether your pickups are active, you can figure that out by opening the cavity up. From where the battery is, there's a red wire that will be wired to the preamp (the black wire will go to the jack). If your pickups have any wire that is spliced in with that red wire, they're active. It doesn't always work that way though, sometimes the power is distributed to the pickups from the circuit board.
    So, I'm going to assume your pickups have two wires coming from them? Probably one black and one white. If they have two wires, regardless of color, they're passive. If they have three wires, they *might* be active - it all depends on where the three wires are wired to.
    Could you take a photo, it would make things easier.

    It's an active signal when you have a preamp in the chain, regardless of whether pickups are active or not.
    As to the whole active vs passive thing, did you read the pickups faq at the top of the forum. That has some good links to check out.
    Again, since Fender have used a bunch of different circuits over the years it's tough.
    Yes and yes.
    I use different techniques depending on the situation. When I'm playing with my own rig, where I know it inside out, I tend to set the amp eq to my 'flat' sound (generally a mild bass boost) and then perform adjustments on my bass mid-set as I want to add/subject bass/treble/mids.

    However, I play a lot of gigs with house rigs. In that situation, rather than having to remember different settings for each brand, I generally leave the amp eq completely flat and eq on my bass. That cuts down on setup/changeover time.
  6. dhclark76


    Mar 26, 2005
    I'll try and get a photo up tomorrow. In the meantime I'll take a look at the wiring and see what I can find according to what you've left.

    As for the knob setup, The stacked is definitely Bass and Treble, but it hadn't occured to me that the third knob might actually be a blend knob. Mainly because there is a 3-way pup switch. Now I'll have to pay better attention and check again, but I'm pretty sure it's a mids knob.

    Your suggestion for the EQing (Bass vs. Amp) makes a lot of sense. I don't end up using other rigs a whole lot so I probably ought to focus on finding and keeping a standard sound dialed in on the amp with all my Bass controls set at the center detent, and then I can always adjust from the bass when playing. The other night I found a setting that I've been pretty happy with on the amp, so I don't expect to mess with it a lot, for now.

    Again, Thanks,
  7. David Wilson

    David Wilson Administrator Staff Member Administrator Supporting Member

    Oct 14, 2002
    Lower Westchester, NY
    ok, you didn't mention that previously so that's why I surmised it might well be a blend knob.