questions on receivers and watts

Discussion in 'OT Technology' started by pantheR, Apr 30, 2008.

  1. pantheR

    pantheR New Member

    Joined:
    Nov 1, 2006
    Messages:
    2,684
    Likes Received:
    0
    Location:
    Washington, DC
    how is a home receiver that produces 100 WPC supposed to power speakers that require say 400W each?

    i've got a few more questions once i understand this.. thanks.
     
  2. Kieffer87

    Kieffer87 Orly OT Supporter

    Joined:
    Sep 23, 2005
    Messages:
    1,491
    Likes Received:
    0
    Location:
    Where the Green Grass Grows
    The speakers are probably 400 watts max. That doesn't mean you need 400w just to power them. The RMS wattage is the more important number to look at.
     
  3. pantheR

    pantheR New Member

    Joined:
    Nov 1, 2006
    Messages:
    2,684
    Likes Received:
    0
    Location:
    Washington, DC
    I understand this, however many speakers RMS value is more than 100W, which is what most receivers can put out per channel

    I'm just trying to figure out what I'm confused on
     
  4. Kieffer87

    Kieffer87 Orly OT Supporter

    Joined:
    Sep 23, 2005
    Messages:
    1,491
    Likes Received:
    0
    Location:
    Where the Green Grass Grows
    You can still power the speakers using the receiver but they would be under powered and may not perform to their full potential. You could always get an external amplifier to power them.
     
  5. El Beaner

    El Beaner OT Supporter

    Joined:
    Jul 18, 2002
    Messages:
    29,938
    Likes Received:
    32
    Location:
    Dallas, TX
    here is ane xcellent example of an external receiver on sale now by an Ot'er

    http://forums.offtopic.com/showthread.php?t=3781383 (shameless plug for ssabripo)
     
  6. pantheR

    pantheR New Member

    Joined:
    Nov 1, 2006
    Messages:
    2,684
    Likes Received:
    0
    Location:
    Washington, DC
    are you telling me a $1000 receiver which does 125WPC can't power mediocre speakers that are more than $125 watts?

    I think what I'm asking here is that, if the total wattage of my receiver is 500W (5.1 system - 100WPC) and I only have 2 speakers hooked up, and each speaker is 200W RMS, will the receiver use 400W (200 x 2) of its 500 watts or will it only provide 100 watts for each speaker?
     
  7. mephistopholes

    mephistopholes New Member

    Joined:
    Sep 16, 2007
    Messages:
    253
    Likes Received:
    0
    Don't get too caught up in the numbers. You do not necessarily need a ton of power to power speakers regardless of what the specs say about the power handling. A clean 100 watts should power most common home speakers just fine. Much of the time the speaker is probably only pulling a fraction of that 100 watts of available power.
     
  8. Doc Brown

    Doc Brown Don't make me make you my hobby

    Joined:
    Mar 31, 2006
    Messages:
    16,404
    Likes Received:
    0
    Location:
    Ohio
    I think the important issue is volume, no?

    What you want to look at is the efficiency of the speakers.

    If they are 90db, and the amp puts out 100 watts rms, then the speakers can put out approximately 110db in volume.
    That's not far off from the typical rock concert levels of around 115db.

    Which is why so many 100 watt receivers have been made. Because it's enough power for most situations.
     
  9. pantheR

    pantheR New Member

    Joined:
    Nov 1, 2006
    Messages:
    2,684
    Likes Received:
    0
    Location:
    Washington, DC
    I agree with you that 100 watts would be enough for me (or ~90db) but what reason would I have then for buying speakers that are more than 100 watts each? If my receiver can't power them. I see a lot of speakers out there that are over 200W, even 300W, RMS and I'm just not seeing how they can tie into the receiver specifications.

    Thanks for all the help thus far.
     
  10. Doc Brown

    Doc Brown Don't make me make you my hobby

    Joined:
    Mar 31, 2006
    Messages:
    16,404
    Likes Received:
    0
    Location:
    Ohio
    Well as has already been stated, 400 is not the requirement, it's the maximum.

    And going to a 200 watt receiver from a 100 watt receiver only increases the sound level by 3db.
    Same thing if you go from 200 to 400.
    So those speakers would only play 6db louder by going from 100 to 400 watts.
    And the rule of thumb is that it takes 10db for a perceived doubling of volume.
     
  11. David02

    David02 Guest

    They don't require 400W... that's just the maximum power that they can handle.
     
  12. james330i

    james330i Imported Redneck

    Joined:
    Dec 14, 2000
    Messages:
    1,890
    Likes Received:
    0
    Location:
    Knoxville, TN
    i wouldn't worry about minimum power requirements on speakers.

    High-end speakers require as little as 25W to perform. It's an issue no one really considers.

    As long as you stay with a respected brand of speakers and receivers, you'll get satisfactory results. Don't get caught up in no-brand chinese speakers with over the top power requirments
     

Share This Page