1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  

Active/Passive ---High/Low

Discussion in 'Basses [BG]' started by Paulb7664, Dec 13, 2006.

  1. Paulb7664


    Sep 30, 2004
    Kent UK
    Hi all
    If I have the EQ set flat on my active bass, is this the same as a passive set-up???
    I was told to set my bass flat and adjust the EQ on my amp. Should I use the Active or Passive input with my bass set flat??

    How do you guys set up. Is it Bass full on and adjust the amp, or Bass flat then adjust the amp, what input to use for each set-up, and why??
    I hope I made this clear.


  2. Pickebass

    Pickebass Supporting Member

    Jul 12, 2004
    San Antonio, TX
    Too many variables...
    some active electronics are not "flat" at all
    some are "+/-" or + only
    Also the amp itself can vary greatly depending on parametric eq and other eq issues.

    In regards to the active/passive switch/input, check your manufacturer's recommendation. Many of the amps I use recommend using the passive input unless the bass is very loud. I have quite a few active basses and only use the active input with one bass

    Typically, I start with everything "flat" on the bass and amp. On the amps I typically set everything at 12 oclock and work from there. Add or take out what frequencies I need based on the venue.

    A couple of things to consider is the natural sound of your amp and what sound made you attracted to the amp. Some people when testing amps test to see what the limits are and if they like the extremes they may purchase the amp. For example, if you test the amp and love the tone with the bass all the way up, you may not be able to get the tone you are looking for at other times, when a room is boomy and the bass frequencies rumble.

    Overall, I think it is a better idea to like the amp sound with minimal tweaking and maximum flexibility. For example, if you are testing an amp, the tone that you desire should consists of small tweaks and still have alot of tonal range adjustments for extreme playing situations. In this manner, you can still get you sound in almost every situation. I don't there there is a magic way of setting up tone. Some believe if you have an active bass, make all the changes there. Others believe minimize the changes on the bass and use the eq on the amp.

    In other words... no right answer
  3. Good questions!

    First, regarding 'flat' tone settings on an active circuit being the same as 'passive', it depends on the preamp. Some preamps have a lot of gain built into them, so the signal will be a lot hotter than the same bass in passive version or passive mode (if you have an active/passive switch). Some pre's like the FBass pre are designed to be very transparant.... I can hear absolutely no difference in tone and output between an FBass is passive mode, and an FBass with the pre engaged but the tone controls set flat (in the FBass's case... 'off').

    However, the general answer will be that most circuits will emulate a 'passive' tone with the tone controls set to flat.

    I would recommend setting your tone controls on your bass to 'flat' and adjusting the amp to 'get your sound'. You get a couple of advantages here. First, most preamps on amps are cleaner and higher quality than the battery powered pre's installed in basses.... so it's better to use the AC powered pre's in the amp to get more of your general tone requirement. Second, that will leave the tone controls on your bass available for easy tweeking on the gig (versus going back and forth to your amp). Finally, really cranking the bass control on an on-board preamp can result in a very very hot input gain that some amps can't handle (or that would require you to use the 'active' input, which to me doesn't sound as good with most amps versus the 'passive' (i.e., non-attenuated) input... even with 'active' basses.

    Usually, a very little goes a long way with on-board EQ!

    IMO, as always.

    Edit: to specifically answer your active/passive input question... unless you are clipping the preamp with the gain set rather low, I would highly recommend using the 'passive' non-attenuated input... less circuitry to go through, and most amps 'like' the increased signal regarding warmth, punch and character.
  4. Machines


    Dec 1, 2005
    Birmingham, UK
    Moderator: basschat.co.uk
    +1. My bass loses so much character when in the active channel.
  5. Paulb7664


    Sep 30, 2004
    Kent UK
    Thanks for all your replys.
    The Bass is a Warwick Thumb 4 N/T. The Amp Ashdown ABM 300 EVO II.
    I'm going to band practice tonight. I will set all flat and let you know how I get on. :bassist:


  6. Paulb7664


    Sep 30, 2004
    Kent UK
    Hi All
    Just got back from band practice. My second outing with The Ashdown ABM 300EVO II, Mini 4x8 & Mini 1x15.
    My Drummer had his Bass drum, mic on. The Guitarist with his Screaming Les Paul + 2 Vocals. Covering songs from. Thin Lizzy, AC/DC, ZZ Top, Thunder, and the likes of.

    I set the E-Q on my Warwick Thumb flat using 2 pickups.

    My amp settings are as follows.
    Input = 2-OC
    Passive/Active = In
    Flat/Shape = Out
    Valve Drive on, set to 10-OC
    Sub-Harmonics on, set to 10-OC
    E-Q on set to.
    Bass = 12-OC
    Mid = 2-OC
    Treb = 2-OC
    Sliders set from centre.
    180Hz up 1
    340Hz up 2
    1.3KHz up 2
    2.6 KHz up1
    Output set = 9/10-OC

    I had to push the mids to cut through the guitar, but I still had loads of low end thump!!
    This set up is ROCK n ROLL :bassist: :D


Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.