450rms to a ten inch sub?

Discussion in 'General Car Audio Discussions' started by evan66, Dec 17, 2006.

  1. evan66

    evan66 Full Member

    i am thining of buying a kenwood kac-9152 runing it at 1 ohm to my 2 ten inch jbl gto subs they are in small truck boxes (.65) here are the specs for the amp

    Mono channel Power Amplifier with Dual Mono Drive Function
    RMS Power: 500W x 1 @ 4 ohms
    RMS Power: 900W x 1 @ 2 ohms
    RMS Power: 900W x 1 at 1 ohms
    RMS Power: 900W x 2 at 4 ohms (Dual Mono Drive)
    Aluminium Die-casting Heat Sink
    Detachable Aluminium Dress Plate & Top Panel Control
    Dual Mono Drive (Bridged Connections of KAC-9152D x 2)
    Gold Plated Input/Output Terminals
    Single Side Exposure of Terminals for Multi Installatio

    will this over power the subs im thinking it will but i dont know
     
  2. aznboi3644

    aznboi3644 Full Member

    It CAN over power them...but an amp will not put out full power constantly...just be careful with the gain control and don't turn it up too high
     
  3. evan66

    evan66 Full Member

    ok now i am debating between that one and this
     
  4. aznboi3644

    aznboi3644 Full Member

    Well what impedance are your subs?

    Link didn't work for me...said hypertext transfer protocol
     
  5. electrolytic

    electrolytic Full Member

    hey guys, can i put my two cents? from someone who has fried about six sets of subs from having an amp more powerful than the speakers! Its great for a while but they will fry eventually.
     
  6. aznboi3644

    aznboi3644 Full Member

    They only fry if overpowered...that's what the gain control is for
     
  7. Ranger SVO

    Ranger SVO Full Member

    Use a little common sense and you should be OK. If it sounds bad then there is a problem. A speaker usually blows because of over excursion or the amp clips. Either way, no excuse, you should be able to clearly hear either case.

    Not true, in my van each speaker is rated at 2500 watts RMS, power output to each speaker is 5000 Watts RMS, I have NEVER blown a woofer. These woofers are 5 years old.

    Gotta B in Vector Calculus
     
    Last edited: Dec 18, 2006
  8. aznboi3644

    aznboi3644 Full Member

    Well i'm in physics and we learned about vectors lol

    Well I mean overpower as in as the coil can't dissipate heat fast enough or the suspension fails....I don't really care what speakers are "rated" at....I know speakers can handle more power than "rated" for if the power is clean...learned that from you don't you remember??? lol

    How you like them vectors?? lol
     
  9. Willy D

    Willy D Full Member

    Well....

    I bought that exact amp....and I have a single 10" JL Audio sub...it is has dual 6 ohm VC....I have not installed it yet....

    Couple reasons I bought that amp.....

    1. I can get a lot of dynamic range out of it....I have no fear of blowing my driver....WHY??? Common sense and using my ears....My front speakers are Infinity Reference separates....I am gonna be running an amp for those that puts out 100 rms x 2.....if I set up my system to sound balanced, I will never even make that amp or the subs work hard...

    2. If I ever put a system in a different vehicle and run more subs or more power hungry subs, I will have enough amp to do so....

    Another thing to understand is the wattage for this (in my case) will be somewhere between 500-900 watts (I will have 3 ohm load).....this wattage is what is AVAILABLE....not what I will be pushing.....What I plan on doing is finding the spot where my head unit clips (if it does clip) and then set my front stage amp to clip at the same time...If I do that, then I have maximized gain structure and that gives me the most head room.....if I set my gain on my sub amp after that, I am basically gonna start at zero with my HU sub out volume in the middle and I will turn my sub amp gain untill I get the low end BALANCED with the rest of the system.....With this setting, I probably will never even push 400 watts through the sub and if I do it will be for brief periods of time.....

    This was my train of thought when I bought that amp....I have never blown an amp, speakers or any audio component (home, car, pro audio)....The first line of defense is to hear the problem and back off.....

    Willy
     
  10. Ranger SVO

    Ranger SVO Full Member

    Find the critical points of the following function f(x,y)=e^x * sin(y)
    Using the Hesse Matrix determine its behavior.

    You are of course right about the voice coil needing to disipate heat. But in most music today there is enough rest time plus better methods are used to cool the coil.

    I just wanna say that I do not recommend pushing double the rated power of your woofers, but 10-25% more than rating can be safely done. AZN is right about cooling. The voice coil needs time to dissipate heat.

    Willy D, I think you'll be fine. I might make one suggestion, adjust your system with the HU just under 3/4 volume. I typically do it this way because at this point my signal to my amps is really clean. The amp has a really clean signal to work with. I really don't like to be at the verge of clipping.
     
    Last edited: Dec 19, 2006
  11. aznboi3644

    aznboi3644 Full Member

    Um...we just learned about scalars and vectors...like force and parallel forces and crap like that lol nothing that complicated

    Ranger...you are crazy to take that math...but I respect you
     
  12. TheViking

    TheViking Well-Known Member


    the equation shows a behaviour typical of a logarithmic attenuation based on parallel universes arrival time in the same quadrant of space. plus or minus a few million.:lol: Sorry, dont know squat about that stuff, i am just a simple hillBilly lookin for my next batch of corn and yeast!!!!


    The ability for a speaker to dissipate heat should really be more accratly advertised. The very words you mention remind of the term "Duty Cycle". Typical in things such as welders I would think that this would be more realistic in a woofers ability to handle/dissipate heat. For example, instead of rating a woofer at say, 1000 watts rms and 2000 watts peak, why not rate it at 1000 watts at 100% duty cycle and 2000 watts @ 10% duty cycle. Or even 1500 watts @ 50% duty cycle. Heckm that same woofer in the example would handle 5000watts @ 3% duty cycle.

    You get my drift i am sure. Just thinking outloud
     
  13. aznboi3644

    aznboi3644 Full Member

    Ahh yes...like how welding machines are rated at 60% duty cycle
     
  14. Ranger SVO

    Ranger SVO Full Member

    Mathematics is my passion. I'll be one of the speakers at the Math and Science Symposium here in Abilene this year (next year Jan 2007). Your welcome to come. My grammer might suck, my spelling may need help, but I understand math.

    Viking, actually your right, I've never heard it related to duty cycle before, but it is an accurate discription. I know that if you run a fuel injector at 100% duty it will over heat and die. In relation to a speaker, 100% duty cycle might represent DC. Excellent analogy.
     
  15. aznboi3644

    aznboi3644 Full Member

    Where is that symposium??

    Where is Abilene??
     
  16. Ranger SVO

    Ranger SVO Full Member

    Texas, and I won't be talking about car audio. I'll be talking about variables and common student errors. You know Symantec, Syntactic, Missing Variable, mistakes that we all make but know better.

    And Viking, you got the first part right, e represents the natural log base