Speaker and Receiver Wattage

Discussion in 'Beginners and Audiophytes' started by BerserkBeagle, Mar 13, 2008.

  1. BerserkBeagle Audiophyte

    BerserkBeagle
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    I know this is a basic question, but I can't seem to find the answer in older posts on the forums. Here it goes...

    Does the wattage of my reciever have to match or be less than that of my speakers (which are 100 watt continuous/400 watt peak)? In other words, will a 130 watt per channel receiver blow my 100 watt speakers?

    Thanks in advance for the advice!
  2. j_garcia Audioholic Jedi

    j_garcia
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    The wattage on speakers is almost irrelevant; they are maximum ratings, not requirements. It is more common to damage speakers by under-powering them than by having plenty of power, so you have little need to worry.
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  3. jamie2112 Banned

    jamie2112
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    No way will that blow your speakers. You can have an amp that is 300 watts a channel into 8 ohms and your speakers will sound better than ever. Unless of course you are going to crank them up to the max and then you might blow a speaker or 2. 100 watt speakers can handle alot of power just use your best judgment and keep the volume nominal...
  4. BerserkBeagle Audiophyte

    BerserkBeagle
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    I thought that was the case, but wanted to make sure. I am looking to get the Denon 3808, but haven't upgraded my cheaper speakers yet.
  5. Pyrrho Audioholic Ninja

    Pyrrho
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    If you crank up the volume control all the way, and put on some music, it is virtually certain that you will destroy some of your equipment, and very possibly your ears as well. And, very probably, the destruction will be immediate.

    Assuming that your speakers are accurately rated (which is very doubtful, as such ratings are not standardized), and assuming that the receiver is rated according to the required standards (continuous RMS output), then you could destroy them with your amplifier, even according to the ratings. You see, that receiver can put out 130 watts continuously, and the speakers can only handle 100 watts continuously (even if we believe the rating, which is probably optimistic BS). Additionally, speakers can handle different amounts of power at different frequencies; typically, tweeters can handle far less power than woofers, and so if you put on a test tone of, say 15 kHz and fed your speakers 100 watts of that tone, it would be very surprising if you did not destroy your tweeters.

    As a practical matter, you do not need to match the power ratings for a speaker and a receiver. I have used, for many years, a receiver rated at 160 watts RMS per channel with speakers rated to handle about 60 watts. Just because a receiver is rated for a certain output, that does not mean that it is putting out that much power at any time ever. It is a claim about what it is capable of doing. How much power it will put out at any given moment will depend upon many things, such as the strength of the input signal and how far up the volume control is turned. Generally speaking, if one puts on music that is at a fairly constant level, one can turn up the volume until one starts to hear distortion, and then turn it slightly down until one hears no distortion, and that will be the maximum safe volume for the system. (Naturally, I am assuming that you are using speakers that are an appropriate impedance for the amplifier you are using.) Of course, if you then used a higher input signal, it will not be safe to have the volume control at the same setting. It is a way of finding the maximum safe volume (sound) level, not a way to find a maximum safe position for the volume control.

    Anyway, do not worry about the power ratings of speakers too much. Just listen and enjoy the music, and if it sounds distorted, turn it down. And if you put on something that is very dynamic, such as the Telarc CD of Tchaikovsky's 1812 Overture, try it out at a fairly low level first, and only gradually try higher levels. Otherwise, when the cannons start, you could destroy things.
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  6. rknoll Audiophyte

    rknoll
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    so ah , i am running a harman kardon pm655 @ 60wpc and have two sets of speakers im working with. tannoy cpa-5 rated for 100 and technics sb-7070 rated 180 music 120 din. am i running the risk of mass catastrophe at low volume playback:cool: and/or party mode?:eek:
  7. jamie2112 Banned

    jamie2112
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    No you are just fine..
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  8. Adam Audioholic Jedi

    Adam
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    Welcome to the forum! Jamie summed it up nicely. Just turn the music down in "party mode" if things start to sound strained. Here's some additional info (if only because I already spent the time looking it up :)).

    The Harman Kardon PM655 receiver is rated at 60 watts RMS into 8-ohm speakers, with a minimum recommended speaker impedance of 4 ohms. The Tannoy CPA 5 speakers are rated at 50 watts RMS (100 watts peak) with a nominal impedance of 6 ohms. So, there shouldn't be any problems there. The Techniques are older, and I didn't spend enough time researching to get more info on them. One thing to note - if you run both sets of speakers at the same time off of that receiver, make sure that the net impedance is not below 4 ohms per the receiver's manual.

    Adam
    Adam,
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  9. rknoll Audiophyte

    rknoll
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    thanks for some input guys . i just got the technics and was wondering if i was going to need a more powerfull amp to drive them without damage.
  10. Adam Audioholic Jedi

    Adam
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    A classified ad on craiglist had those speakers listed with an impedance of 8 ohms. So, I don't think that you are going to have any issues with damaging those speakers. The real test will be if they are loud enough for you (without sounding strained) when you use the PM655. If not, then a more powerful amp would certainly be a consideration.
    Adam,
  11. no. 5 Audioholic Field Marshall

    no. 5
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    Low volume; no. Party mode; it would depend on how loud. :eek:

    A speaker can never be destroyed by sending it 'too few' watts, if an amplifier doesn't have enough power for the listening level, or the current reserves for a given impedance, it can clip which results in more power being sent to the speaker.
  12. mtrycrafts Audioholic Slumlord

    mtrycrafts
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    How are these two sets connected to that receiver?
  13. rknoll Audiophyte

    rknoll
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    at the moment only one set hooked up, I'm planning on wiring them both up. Tannoys from the ceiling and obviously leaving the 7070's on the floor. i have enough outs to have them both set up. a or b and a+b.
  14. rknoll Audiophyte

    rknoll
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    loud would be shots and beers and king crimson
  15. rknoll Audiophyte

    rknoll
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    Im ignorant in impedance matters. owners manual for amp say rms 60wpc both channels driven into 8ohms 20-20,000 hz
  16. rknoll Audiophyte

    rknoll
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    no edit button so i must make new posts instead of updating.
    owners manual says " two speaker systems can be connected to this unit. The minimum speaker impedance should be 4 ohm when only one speaker system is connected. When two speaker systems are connected care should be taken that net impedance does not become less than 4 ohm." ...am i doing that? how do i know?
  17. Adam Audioholic Jedi

    Adam
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    The combined impedance is something that I was waiting for someone else to answer, as it is the key. As I mentioned earlier, your Tannoy speakers are 6 ohms nominal, and your Technic speakers are 8 ohms nominal. Someone here can surely tell us what the combined impedance is. That someone isn't me, though. :)
    Adam,
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  18. rknoll Audiophyte

    rknoll
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    so what we need is a math problem...hmmm. :confused:

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