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Speaker Impedence Advice

Discussion in 'Home Cinema Speakers' started by leepee2000, Nov 25, 2003.

  1. leepee2000

    leepee2000
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    Hope someone can help!

    I have looked through the forum and have found some advice advice on speaker impedencae but not for my particular problem.

    I have bought a Sony DAV S880 and a set of 5 Koda speakers ( I hadn't heard of them either ). Both were bargains so I am loath to replace either.

    My question is this . . .
    The Amp is rated at 3 ohms, and the speakers are rated at 8 ohms, what damage or effect to the sound quality if any will occur if I put these together?
     
  2. buns

    buns
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    the question is very hard to answer because we dont know what exactly a 3ohm rating on the amp means..... but, i would be confident to say that 8 ohm speakers should be fine with all but the worst amps. So keep it at normal levels and there wont be any problems

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  3. Crustyloafer

    Crustyloafer
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    Your DAV S880 is rated at 3 ohms to give the impression it is reasonably powerful. However this system is only designed to power the speakers that came with it. If you use anything else then you risk damaging either the onboard amp or more likely the speakers. An amp rated at 100 watts inot 3 ohms is only likely to give 15-20 watts maximum into 8 ohms and so is not likely to be able to drive your Kefs properly. Save your money and buy a proper AV amp.
     
  4. leepee2000

    leepee2000
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    Oh well, guess i'll have to look for some new speakers as I already have the amp and I think its ace, do I have to find 3ohm speakers or can I use 4ohms?

    Guess i'll have to put the speakers back on e-bay!
     
  5. bob1

    bob1
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    Don't use 4ohm speakers use 8ohm,as already metioned the 3ohm rating was given into fooling you into thinking you have a more powerful amp.As long as you don't run the amp too high so things start to clip and distort you should be fine.
     
  6. Reiner

    Reiner
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  7. leepee2000

    leepee2000
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    It seems that every time I ask this question I get a different view,

    I guess that now my questions are this . . .

    "buns" says "keep it at normal levels and there wont be any problems" . . . and "bob1" says "As long as you don't run the amp too high so things start to clip and distort you should be fine" What are normal levels?
    What is too high?
    Can I use it up to 60, 70 or 80%?
    "Crustyloafer" warns "use anything else then you risk damaging either the onboard amp or more likely the speakers" is this being a bit over protective?
    He also adds "An amp rated at 100 watts into 3 ohms is only likely to give 15-20 watts maximum into 8 ohms and so is not likely to be able to drive your Kefs properly" the speakers I have are Koda's, they were only cheap but I still dont want to bust them, they are rated high enough to take the power but if they aren't going to make the best of the Amp I would rather change either the speakers - http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=3061068557&category=1499
    or the Amp - http://www.superfi.co.uk/index.cfm/page/moreinfo.cfm/Product_ID/1235

    Any thoughts or advice would be appreciated.

    Lee
     
  8. buns

    buns
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    Normal levels...... in other words you can have it relatively loud, but if the windows are shaking then it is much too loud.

    Crusty is being over protective. In fact, 100 watts at 3 ohm with a low end machine is more likely to corespond to well above 50 watt at 8 ohm.

    For a good amp, the power will double as you half the impedence, for something not so good, it will less than double.

    I dont know the speakers, never seen or heard of them previously. But they are quite big..... so i would perhaps take a bit more notice of crusty. You should maybe consider getting something a little bit smaller.

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  9. leepee2000

    leepee2000
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    Thanks for the advice, but as usual I just end up with more questions . . .

    I have found a set of DAV s880 speakers to match the Amp but they are £300 !

    So far the system has cost me £180 for the Amp and £130 for the speakers, cables etc. not counting p&p etc. which should I change? I just don't know which to get rid of cos I like them both ! The Sony Amp is ace ! it does it all Pro Logic 11 SACD 600w and the proper speakers for the set look cool ! on the other hand the Koda speakers look cool but may sound cack !

    Thoughts anyone !

    Lee
     
  10. buns

    buns
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    Oh..... im sorry...... you already have it all? I got the impression you were just buying it!

    That being the case, unless you are unhappy with it, leave it as it is! If you listen at sensible volumes - for instance, could you talk to someone when listening? - then there wont be any big deal.

    In any case, the sony speakers wouldnt be the best way to spend your money. Unless you really have spare you must spend, id just let it be

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  11. leepee2000

    leepee2000
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    Thanks a lot fella, what I will probably do is keep it low and keep an eye out for a bargain amp to go with the Koda thingys !
     

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