Okay, what is "crossover"?

Discussion in 'Amps and Cabs [BG]' started by dgce, Jan 12, 2005.

  1. dgce


    Jun 17, 2001
    Massachusetts, USA
    I'm really embarrassed to be asking this but hey; I just don't know what it is. Whenever I read reviews on bass cabs and amps, there are often references to "crossover" (crossover switch, knobs, etc.). I even see there's a new thread here regarding crossover on an Avatar cab. Could some kind soul give me the scoop on what exactly this means, its function, its importance?


  2. IvanMike

    IvanMike Player Characters fear me... Staff Member Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    a crossover divides frequencies into highs and lows. more complex crossovers divide frequencies into 3 or 4 sections (highs, high mids, low mids, lows)

    there are 2 basic types

    a passive crossover will be found in a cabinet. typically these are cabs with a tweeter and one or more "woofers" (like a 4x10 + horn) past a certain frequency, (say, 2.5 kHz), all frequencies are sent to the tweeter

    an active crossover is plugged into a power source and divides the signal into 2 or more frequencies. some players use this to have "biamp" rigs where highs go to one cab and lows go to another. These are much more common on pa than bass rigs
  3. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    dgce...there is no need to be embarrassed. When someone else has the guts to speak up and ask a question, it gives us all a chance to learn something new, either technically or perhaps a better way to explain a technical issue.

    IvanMike covered most of it, but the other function of a crossover is to protect the higher frequency elements (midranges, tweeters, etc.) from damage. The crossover needs to be matched to the driver that it's protecting to make sure that the crossover frequency is high enough and the rolloff (of lower frequencies) is fast enough to reduce the chance of damage.
  4. dgce


    Jun 17, 2001
    Massachusetts, USA
    Okay, hold on now. So if I have 2 cabs, the Crossover will negate how much highs go into one cab and the lows go into the other (now I'm not talking about biamping here; I know what that one is!). However if I'm using just one cab, the Crossover will send x-amount to the tweeter and x-amount to the woofer? Er...right?

    Btw, thanks for the help!

  5. A high pass crossover will send everything above a certain "crossover" frequency to the horn. The Speaker gets everything but will only produce what it was designed for.
    For instance the circuit may be designed for 3KHz. It passes mostly 3khz and above.

    A low pass crossover designed for say 3khz will pass everything below 3 khz to the speaker.

    A 2-way crossover has a high pass for the horn and a low pass for the speaker and if designed correctly will make a smooth transistion of tone from the horn to the speaker and visa versa. Using the above frequency of 3khz, everything below 3khz goes to the speaker and everything above 3khz to the horn. Now that is somewhat simplistic as they actually start to turn on or off somewhere near that frequency.
  6. metron

    metron Fluffy does not agree

    Sep 12, 2003
    Lakewood Colorado
    close ;)