DB350s bottoming out, popping--solution?

Systems
Systems Posts: 14,873
edited September 2003 in Car Audio & Electronics
I have an Alpine 9805, 50 watts x 4, and I just got two pairs of Polk DB350s to replace my stock speakers.

They sound GREAT, but when the volume gets up a bit (not too loud, actually), they'll pop when there's a bass hit or sound hit (e.g., Counting Crows Elizabeth song from Recovering the Satellites--not a huge sonically stressing song). It seems from research that they're bottoming out. Is my solution to get blocking resistors and put them inline? Where can I get them? My two usual sources are Circuit City and Tweeter (nee Bryn Mawr Stereo).
Testing
Testing
Testing
Post edited by Unknown User on

Comments

  • Systems
    Systems Posts: 14,873
    edited September 2003
    Sorry, made a mental typo when I composed the above post. I meant DB 570s.
    Testing
    Testing
    Testing
  • sntnsupermen131
    sntnsupermen131 Posts: 1,831
    edited September 2003
    your best solution is to get an amp
    your speakers are popping b/c the head unit is clipping(its trying to push out too much power and when it cant it clips--causing your popping noise)
    while ur head unit is rated at 50x4...its actually like 22x4, and even then, those 22 watts arent very "clean" watts
    with an amp, they would get louder, distort less, and sound a lot better
    -Cody
  • Systems
    Systems Posts: 14,873
    edited September 2003
    Thanks--this makes sense. If I faded the channel to all front or all rear, the popping went virtually away. Clipping seems to explain that better than bottoming out. So I need an amplifier.

    Maybe this would help keep my Alpine from getting so hot, too.
    Testing
    Testing
    Testing
  • PoweredByDodge
    PoweredByDodge Posts: 4,185
    edited September 2003
    dave it'd probably cut the temperature of your alpine head unit in half.

    also - yes - an amp will eliminate that clipping problem as long as you get a good amp -- and with sufficient power (or hell the amp will clip too!) --- i would suggest at least 50 x 4, but most likely you wil lnot need more than 75 x 4 tops.

    also -- resistors are a no no -- you odnt put resistors in line with speakers.

    its capacitors.

    an appropriate value capacitor will cut out some of the very very low bass that is going to yoru speakers (stuff that your speakers cannot reproduce - causes them to distort - and normally would be sent to subwoofers).

    if you are not getting a sub - i would suggest a crossover value of about 60-65 hertz. maybe more / maybe less depending on your habits -- but 60 would probably keep yoru speakers from wacking around aimlessly, while still giving you respectable bass.

    if you are getting a sub -- that range becomes 75 to 100 hertz.

    anyway - once you figure out that point that you want - you do a little math and figure out the value of capacitor you need... in which case you then go to radio shack and dig something up.

    4 capacitors to give you a 6 db/octave slope on 4 speakers should cost you no more than 5 dollars total (1.25 each) from radio shack -- much cheaper online, but most onlne parts stores have minimum dollar amount orders (ie - digikey charges 5 dollar surcharge for any order under 25 dollars).

    however, fear not -- because if you do buy a good amplifier then it will come with an onboard high pass/low pass adjustable crossover.

    this means that you wont need any capacitors at all -- with a flip of a switch your amp will do the crossing over and filtering for you. and with an adjustable dial it will allow you to play around with all different settings from anywhere like 40 to 400 hertz depending on the company of the amp.

    if you'd like amp suggestions, hit us up with a price range and suggestions will be forthcoming.
    The Artist formerly known as PoweredByDodge
  • Systems
    Systems Posts: 14,873
    edited September 2003
    I'm looking at both amps and blocking capacitors now.

    My stereo system is made more complex by the fact that I actually have six speakers--two front channel and four rear channel. In looking at the stock system, it seems that the rear channel speakers are wired in parallel to keep them at 4 ohms. Does that mean that the front speakers are getting twice as much available power as each of the rear speakers? By the first reply above, each front speaker would be getting 22 watts and each rear speaker might be getting 11 watts. Pretty lame. The Polk DB570s are rated at 60 watts, 180 peak. Once I replace my wayback speakers, all six will be DB570s (the waybacks are still stock).

    If the rear speakers are wired in series, would they even work right? My guess that they're wired in parallel is based on the fact that they always worked with the stock speakers before--maybe that's wrong.

    At any rate, the only other thing I'm adding to my system is my old subwoofer (a 10 incher), but I have a 30watts x 2 amplifier for it that I run mono.

    Here's a final question--if I can't get a new amplifier right away, am I OK in running the Polks if I don't turn them up to the point of distortion for a few weeks?
    Testing
    Testing
    Testing
  • PoweredByDodge
    PoweredByDodge Posts: 4,185
    edited September 2003
    dude here's one othe rproblem

    6 speakers -- now u say the rears are in parallel, that's a no no.

    see you go and change those and you'll have the a 4 ohm load up front and a 2 ohm load out back.

    that's fine as long as you run a 4 channel to them.

    the result will be your rears getting about 80% the power of your fronts as most amps dont double power into 2 ohms but do more like 150% instead of 200%.

    anyway... make sure your wiring is straight (correct) otherwise you're gonna start cooking ****.

    i would be sure all speakers were replaced with aftermarket (polk)

    and then take a multimeter and measure resistance for the speaker lines behind the head unit... then choose your amp based on that reading.
    The Artist formerly known as PoweredByDodge