amp wattage question

Discussion in 'Archived Threads 2001-2004' started by Tom_Price, Jul 24, 2002.

  1. Tom_Price

    Tom_Price Stunt Coordinator

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    I want to add an amp to my 7.1 setup. My question is that I have Klipsch Reference speakers all the way around and they do not have the same wattage ratings.


    Fronts-RF-3II- rated at 150W max continuous, 600W peak
    Center-RC-3II- rated at 150W max continuous, 400W peak
    Surrounds(L,R)-rated at 110W max continuous, 300W peak
    Surrounds(back)-rated at 150W max continuous, 400W peak

    I am looking to add an amp either a single 7 channel B&K 7270, or a 5-channel, with a seperate 2-channel to power the surround back speakers. The problem is that I am planning to add an amp that would supply 200 watts to each channel, but wouldn't that exceed the speakers ratings, and cause damage to the speakers in the long run? What wattage rating should I be looking at? The rooom it is going into is very large.

    How else could I go about this?

    Thanks in advance for the help.

    BTW, I am going to use my Onkyo 898 as the pre-amp.
     
  2. Jason Wilcox

    Jason Wilcox Supporting Actor

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    being that they are klipsch and are all well more sensitive than 90db.....i doubt you could push 200w into any of those without serious hearing problems....unless of course....your room is huge

    so...i don't think you have anything to worry about
     
  3. GordonL

    GordonL Supporting Actor

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    Use this to figure out how much power you need http://www.myhometheater.homestead.c...alculator.html
    My first thought was you probably can get away with 120wpc with the Klipsch because of their relatively high sensitivity. But then, plugging in the numbers at that site with a 16ft listening distance shows you can get away with a 60wpc amp (106 db at the listening position)!
     
  4. Aaron_Smith

    Aaron_Smith Stunt Coordinator

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    It's much more dangerous to drive speakers with too little power than with too much. If your amp is underrated then the signal will clip at high levels, which causes the voice coils to heat up, which may eventually lead to blown drivers(dramatic oversimplification but you get the point). There also can be sonic benefits to using the higher powered amps because they won't be driven as hard to acheive the same listening level, which means they'll operate longer in their linear region which will minimize distortion.
    All that being said, I understand the Klipsch are very sensitive so you shouldn't need a lot of power to make them sing. Your current receiver can probably drive the speakers very loud, but an external amp may allow you to drive them very loud and very clean. I'm not sure of the impedance of the speakers, but if it's below 8ohms nominal then be sure you're using a high current amp. Published amp wattage ratings usually tell you very little about how an amp does with low impedance speakers, but it can make a huge difference in sound.
     
  5. Rob Rodier

    Rob Rodier Supporting Actor

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    That is extremely well said Aaron.

    -rob
     
  6. Mark Tranchant

    Mark Tranchant Stunt Coordinator

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  7. Phil Mays

    Phil Mays Second Unit

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    Tom,
    You have a very similar setup as I do.
    Onkyo 797
    Klipsch KLF-20 Mains
    " RC-7 Center
    " RF-3 Surrounds
    " RC-3 Rear
    I just placed an AMC 150 watt per channel amp in the system and the power difference was dramatic. My listening room is about 16' x 18' x 9'. With those highly sensitive speakers we (my wife)can hardly stay in the room when volume is turned up to 70 (scale of 0-100). So based on that and the previous great posts you would not be able to take it.
    I do not think the 200watt amp will hurt a thing and as others have said it will actually give you cleaner power with less distortion at your listening level, that is unless you wear earplugs and crank it to compensate for that
    [​IMG] .
    Go for it...I know it will bring out detail in those RF-3's you didn't know you had...mine did[​IMG]
    Of course another item to consider is speaker placement.
    Let us know how it goes as I am considering BI-AMPING with a 200WPC amp.
    Phil
     

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