Rotel RB981 into 4ohms

Discussion in 'Amps, Pre-Pros & Receivers' started by stato, Jul 3, 2006.

  1. stato Junior Audioholic

    stato
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    Hi,
    I bought the Rotel about 5 years ago and from memory is stable at 4ohms but cant find any info to verify that. Also if it is how much power would it be per channel considering it is rated at 130wpc @ 8 ohms etc.
    Any info would be appreciated... Thanks.
  2. mike c Audioholic Warlord

    mike c
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    http://europe.rotel.com/support/pdfs/manuals/rb981.pdf

    looks like this is the old model of the current Rotel RB1070
    maybe you should search the RB1070 to get an idea on your 981.

    www.htguide.com

    has a dedicated rotel sub forum, i've seen them mention the 4ohm rating of the 1070.

    if I had to guess, the 4 ohm rating has to be 160-180wpc (low THD) 200w maybe for 1% THD
  3. mike c Audioholic Warlord

    mike c
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  4. stato Junior Audioholic

    stato
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    Thanks mike c I will look them up now.
  5. markw Audioholic Overlord

    markw
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    I have their 991 and it's had no problems four ohm driving Maggie 1.6's...

    ...but these are a fairly constant four ohms. Your speakers impedance curve may come into play here. i.e. Some speakers drop below four ohms even though they are rated at four ohms (nominal).

    Oh, the 991 is rated at 200 wpc @ eight ohms and 300 wpc @ four ohms.
  6. stato Junior Audioholic

    stato
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    Thanks markw.
    Going on your specs that 200w becomes 300w @ 4ohms for your 991 would it be fair to say the 981's 130w becomes about 190w per channel?
    Also, I have a set of Jamo E870 fronts rated at 150w constant to 220w peak 4ohms. I can not find a sensitivity rating for them but do you think they would benefit from a bit more power from say a Rotel1070?
  7. markw Audioholic Overlord

    markw
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    IMNSHO, any speaker can benefit from more power.

    It leaves more headroom for those instantaneous peaks. But, common sense should always prevail: Is something starts to sound funky, turn it down NOW! Something is complaining.

    Dunno about the 4 ohm spec on the 981 but for a ballpark figure, I'd say it's about right. It's most certainly considrably more than the 8 ohm spec.

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