No announcement yet.

Sound cancellation w/ 3-way..??

  • Filter
  • Time
  • Show
Clear All
new posts

  • Sound cancellation w/ 3-way..??

    I searched and read a few posts re: speaker cancellation, but they didn't really touch on what I had in mind...

    I wanted to do a front install w/ a 3-way speaker set (ie 7" woofer, 4" mid, 1" tweet)... My design was to have the woofer in the door slightly aimed at the shifter... In the kick panels would be the mid and tweet aimed at the opposite headrest... My main concern is cancellation by having the woofer basically playing across the mid and canceling the sound, I know there is usually some overlap by design in the crossovers, but does that take into account this possible scenario..??

    Anyone have any personal experience with this or possible info, or links..??

    I kinda have it in my head that it won't be too noticeable if at all, similar to where I work in the ER everyone is talking but no ones voice is "cancelled" by another... I know, bad analogy, but in a crowded environment the voices kinda combine although they are in a narrow band, so in audio reproduction the low, mid and hi should combine and not cancel, right..??

    I have been planning a setup like this for a good while, and originally thought of using (all Directed Audio), a s800 pair mounted under the dash facing downward, and a s550 pair in the doors with the tweets mounted in the stock kick panels... but it would be alot easier to sorta turn the door into a box, than make fibeglass box to fit under the dash...

    Thanks in advance for any info...

  • #2
    you're on the right track, the voices should combine and actually amplify at the point they cross... Or at least that's what i've been told. The analogy i was taught was using regular ocean waves, when they come together they don't just cancel and make still waters, they crash into eachother.

    The crossover point for the audio would i GUESS if i'm thinking properly be the key point where you have to focus on to be sure of no overlaying frequencies


    • #3

      I guess so...

      So identical frequencies cancel, while others combine... It reminds me of this time I was driving my accord pulling along a civic and for a brief moment (3-4 sec) our exhausts silence each other... RRRRrrrrrr..........rrrrrrrRRRRRRR... I thought the engine shut off for a second...

      So... I should have no fears, the only concern is the sound pressure from the cone of the woofer, hitting the mids, but it is kinda open air, and therefore is very little pressure...

      Up next: Turning unused door space into a sealed box, via fiberglassing...



      • #4
        identical frequencies combine, they don't cancel, they only cancel if you have one out of phase and one in phase, they'll cancel because ones pretty much... pulling and one's pushing i guess that's an easier way of saying it.


        • #5
          Originally posted by jbeckford1 View Post
          It reminds me of this time I was driving my accord pulling along a civic and for a brief moment (3-4 sec) our exhausts silence each other... RRRRrrrrrr..........rrrrrrrRRRRRRR...
          Fart can-cellation.

          You'll have to adjust each speaker in relation to the driver's position. Set up temporary positions so that you can aim them "on the fly" without committing to a position until you're happy. You typically only have cancellation with speakers that directly face each other (opposite phase cancellation)--but I doubt you'll see anything like that in this case.


          • #6
            A wave form exapnds in a sphere, unless inhibited.(IE a baffle etc)Therefore you can and do get combing (summing and nulls, which show up on an RTA spectrogram ..hence "combing") whenever these sphere interact on the same frequency (normally at quarter phase points)

            You need only concern yourself of how this effects the listening position.