Just a Suggestion

Discussion in 'Car Stereo Speakers' started by Ranger SVO, Jan 3, 2008.

  1. Ranger SVO

    Ranger SVO Full Member

    Not the same thing, not even close. By using the fader we would not only reduce level, directionality would still be there.

    By wiring the single speaker out of phase, we retain all the volume of 4 speakers, but now it all seems to be coming from the front.

    Told you that this was a difficult concept to grasp.
     
    Last edited: Jan 9, 2008
  2. aznboi3644

    aznboi3644 Full Member

    kinda like calculus lol
     
  3. pedro quiroga

    pedro quiroga Well-Known Member

    ok.i think i understand it.
     
  4. Ranger SVO

    Ranger SVO Full Member

    Its really not that difficult, Bikini Calculus can help you. Not only is it fun to watch, it very accurate.

    I said it was hard to understand and it is.

    I've tried the crossover at the shop for a few days and it works well. I first put an MB Quart tweeter on it. It sounded a little tinny and it also sounded like it was crossed over too high. I then put it on a factory replacement 3-1/2-inch speaker, it sounded great.

    Finally I put it on those cheap no name tweeters, they also sounded great. I wounder what was going on with MB Quart tweets?
     
  5. pedro quiroga

    pedro quiroga Well-Known Member

    ok.lets see if i DO understand it.the output was there but you couldnt localize the speaker.making it sound like it was coming from up front.

    is that right?
     
  6. Ranger SVO

    Ranger SVO Full Member

    You got it :lol:

    I just wanna add one thing, this putting one rear speaker out-of-phase will not always work. The rear speakers needs to be some distance from the front. Also the rear speakers need to be some distance from the listener. An example of a truck this will not work in would be a standard cab Chev truck with 6-1/2-inch speakers in the doors and 4 x 6 in the panel right behind the driver. It might work in the extended cab, but I don't know.
     
  7. pedro quiroga

    pedro quiroga Well-Known Member

    if my head didnt have time alignment then the 6x9 right behind me would scream.
     
  8. aznboi3644

    aznboi3644 Full Member

    I just got a few tweeters that electro sent me...I opened up the shrink wrap and theres a 4.7 ufd cap on. I looked it up and its about 8500Hz crossover...seems quite high.

    Ranger, I was thinking about buying a few .15mHy coils and make a second order highpass using this 4.7ufd cap for a 6000Hz crossover point....12db/octave

    What do you think??
     
  9. pedro quiroga

    pedro quiroga Well-Known Member

    those tweets he sent you maybe arent able to handle the lower freqs.....?maybe.

    hell, they were free.do it and see.
     
  10. aznboi3644

    aznboi3644 Full Member

    well if they are crossed over around 8500Hz with a first order than they are 6db down at around 4250Hz and 12db down at 2125Hz

    So if I made a 12db/octave crossover at 6000Hz than they'd be 12db down at 3000hz and 24db down at 1500Hz....seems like they'd be happier with that...dunno though cuz I've never made any crossovers before...just want to check
     
  11. pedro quiroga

    pedro quiroga Well-Known Member

    um....ok.you lost me at "well".lol
     
  12. Ranger SVO

    Ranger SVO Full Member

    Perfect, your thinking and your thinking is right. Because of the steeper slope, you can go to a lower frequency safely. For a 12dB/octave (one cap and one coil) 6000Hz is a pefect crossover point.

    Your assuming that your dealing with a linear equation, your not (but your close enough), however your assumptions are 100% correct. The tweeter will be happier with the 12dB/octave at 6000Hz.:lol::D
     
    Last edited: Jan 12, 2008
  13. pedro quiroga

    pedro quiroga Well-Known Member

    darn you two.

    math is my enemy.
     
  14. Ranger SVO

    Ranger SVO Full Member

    Math is your friend

    Azn, start building, you've got it all figured out. One 4.7 microfarad cap and one 0.15mH coil. Your calculations are right. You should be able to find those coils pretty cheap. Iron cores are considered better, but for what we do, air core works great. I use air cores.
     
  15. pedro quiroga

    pedro quiroga Well-Known Member

    what i meant was.i've always been real bad with math.
     
  16. aznboi3644

    aznboi3644 Full Member

    Now to find an electronics parts store in my area
     
  17. Ranger SVO

    Ranger SVO Full Member

    I just thought of something. Why not go for a 18dB per Octave filter. The slope is getting steep so your crossover point can be as low as 5000Hz. Thats what I did in my truck. I think the values were 5-micro (4.7 is close enough) and 16-micro. I don't remember the coil value but it was 0.1 or 0.15mH. either value would work.

    Think about it. Because the slope is steep, you can go lower and therefore more audio from the tweeters. Think about it.
     
  18. aznboi3644

    aznboi3644 Full Member

    Well...I would go with an 18db/octave filter but I have no idea how to wire the components together.

    Also I think i found a place that sells inductors but the bastards never called me back
     
  19. Ranger SVO

    Ranger SVO Full Member

    I made a mistake, the first cap C1, needs to be 5.6-microfarad. The other values are right.
     

    Attached Files:

    Last edited: Jan 17, 2008
  20. aznboi3644

    aznboi3644 Full Member

    so ranger what value cap and coil do i need??? I'm confused now