amp for 2 12" Polk GXN124 Subs

Systems
Systems Posts: 14,873
edited July 2003 in Car Audio & Electronics
I have a Rockford Fosgate Punch 500S amp and was wondering if that was enough to power the 2 12" subs? And if not... can someone please tell me wut amp I should get

Thx!
Testing
Testing
Testing
Post edited by Unknown User on
· Share on FacebookShare on Twitter

Comments

  • Steve@3dai
    Steve@3dai Posts: 983
    edited July 2003
    Yes, that should be fine. The GNX series is fairly sensitive, so it doesn't take too much to get them going. I only have about 175-200w going to my MM12 and I get quite a good bump ;)
    LSi 9/C/FX
    Arcam AVR-200
    · Share on FacebookShare on Twitter
  • PoweredByDodge
    PoweredByDodge Posts: 4,185
    edited July 2003
    actually, it may or may not be...

    the 500S is a stereo amp doing roughly 125 x 2 at 4 ohms // 250 x 2 at 2 ohms // 500 x 1 bridged at 4 ohms.

    now your subs are GNX 12's, but what impedance??????????

    are they single 4 ohm coil?
    dual 4 ohm coil?
    single 8 ohm coil?

    if they're single 4 ohm, u can probably run them stereo, which is slightly "hoopty" but hey, ya can't win em all.

    if they're 8 ohm or dual 4 ohm, u can rig them up to the amp bridged, which will give you 250 per sub, 50 more than you'll need, since they wont really take much over 200, but more power is better than less.

    its gonna depend on the impedance of the speaker so flip them over and look on the magnet it oughta say somewhere... or just look for the number of pairs of speaker terminals and then test the resistance.
    The Artist formerly known as PoweredByDodge
    · Share on FacebookShare on Twitter
  • Systems
    Systems Posts: 14,873
    edited July 2003
    They are a single 4ohm sub
    Testing
    Testing
    Testing
    · Share on FacebookShare on Twitter
  • PoweredByDodge
    PoweredByDodge Posts: 4,185
    edited July 2003
    ouchy -- i was hopin they weren't...

    well.... you can run them, but you'll have to keep a few things in mind.

    1- you'l have to do it STEREO... one sub on the right channel, one on teh left.

    2- you'l have to have these subs in separate chambers (either separate boxes, or a box that has a divider wall inside so it basically works like separate boxes) because the R and L channels will put out slightly different sounds which will cause the speakers to fight with each other which is a "no no"

    3- you'll only get 125 per sub. which may work for u.. may not.. me, i like power and would try to shoot for 200.

    if you wanna go amp hunting...

    RF makes a 301M which will do in the ballpark for 350 x 1 at 2 ohms so u'd get 175 a sub and it would be true mono so you'd end up being able to leave them in the same chamber.

    or go with something like profile ... Profile CA600M does like 425 x 1 at 2 ohms mono and its only 150 bucks retail at crutchfield.com right now.
    The Artist formerly known as PoweredByDodge
    · Share on FacebookShare on Twitter
  • Steve@3dai
    Steve@3dai Posts: 983
    edited July 2003
    Could you run them in series or parallel?

    Bridge them from the amp and do that. Might work...
    LSi 9/C/FX
    Arcam AVR-200
    · Share on FacebookShare on Twitter
  • PoweredByDodge
    PoweredByDodge Posts: 4,185
    edited July 2003
    he's got an amp that is 125 x 2 at 4 ohms stereo / 250 x 2 at 2 ohms stereo / or 500 x 1 at 4 ohms bridged.

    the subs are SINGLE 4 ohm coil.

    which means unless he wants to risk damaging the amp, he can ONLY run two 4 ohm subs in one manner --- stereo... that'll give 125 x 2.

    "bridge them at the amp" -- whats that mean? the only way to bridge an amp is at the amp -- you dont bridge subs, you bridge amps.

    if he parallel's the subs, and bridges it, he'll get a 2 ohm load, which will most certainly cause damage to it over time as well as screw up general operation.

    if he series's the subs and then bridges it, he'll get 250 x 1 into an 8 ohm bridge, which will result i 125 per sub -- same as if he ran stereo -- the only advantage would be a mono signal thus not requirig him to use separate chambers for the subs.
    The Artist formerly known as PoweredByDodge
    · Share on FacebookShare on Twitter
  • Steve@3dai
    Steve@3dai Posts: 983
    edited July 2003
    Bridge the amp in the traditional manner, but put the speakers in parallel.

    I think the RF could handle 2 ohm.
    LSi 9/C/FX
    Arcam AVR-200
    · Share on FacebookShare on Twitter
  • PoweredByDodge
    PoweredByDodge Posts: 4,185
    edited July 2003
    you think wrong.


    their cases in general are far too small to support sufficient cooling... regardless of whether the circuitry could take it or not (which is a 50/50 toss up... if he scoped the output at 400 watts on the dot at 2 ohms, it probably could take it, the decrease in output power would suffice to stabilize the circuit)... there is by no means sufficient cooling. they pack too much amp in too small a case. and the bd-design is not very freindly to being pushed beyond its means.

    edit note - just realized i made reference to the mono RF when speaking on the stereo RF's... either way tho -- its not gonna be happy beneath its rated impedance...
    The Artist formerly known as PoweredByDodge
    · Share on FacebookShare on Twitter
  • sntnsupermen131
    sntnsupermen131 Posts: 1,831
    edited July 2003
    Originally posted by PoweredByDodge
    you think wrong.


    their cases in general are far too small to support sufficient cooling... regardless of whether the circuitry could take it or not (which is a 50/50 toss up... if he scoped the output at 400 watts on the dot at 2 ohms, it probably could take it, the decrease in output power would suffice to stabilize the circuit)... there is by no means sufficient cooling. they pack too much amp in too small a case. and the bd-design is not very freindly to being pushed beyond its means.
    take his word on it...he tried to fix my rf bd1000 that i fried cuz it got too hot
    -Cody
    · Share on FacebookShare on Twitter