Underpowering JBL Series S HT System

Discussion in 'Archived Threads 2001-2004' started by Robert Tonkin, Aug 19, 2002.

  1. Robert Tonkin

    Aug 16, 2002
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    First off allow me to add my appreciation and kudo’s to the long list of others who find this forum exceedingly informative and useful.
    I’m building a HT system that will double for mostly classical music listening. Music will comprise 70%, HT 30%. I’m very drawn to the SACD format for classical music. Sony will pull this one off, but that’s another post.
    I have decided to go with the JBL S series for speakers, 38ii’s for mains and s26ii’s for rear surrounds. My living room is 25 foot square completely open with a vaulted ceiling.
    My request for advice focuses around the receiver. I plan on adding a ROTEL 2 channel amp down the road to take full advantage of the two 38ii’s in stereo mode and use my receiver as a preamp. How low down the power rung in quality receivers can I get away with now, for HT use, and still appreciate SACD quality in the JBL's? I’m considering a 70 watt 5.1 receiver to drive the system until I add the Rotel. Am I in danger of “clipping” my JBL’s with 70 watts? Will I be disappointed when I play SACD’s and the 26ii’s don’t pull their weight? Should I rub my neck, write a check, and go for a 100 watt receiver now, even though I’m buying a boatload of bells and whistles (6.1,7.1 THX, expensive remotes) I don’t want to get the extra 25 watts. I wish to make sure the center, surrounds and sub have adequate power for HT use, but not much more. Comments would be appreciated.
    “The definition of an intellectual is an individual who has been educated beyond their intelligence.”[​IMG]
  2. John Garcia

    John Garcia Executive Producer

    Jun 24, 1999
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    The sub's power, ideally, should not come from the receiver. Most subs these days are internally amplified.
    The extra 25wpc will be worth it, IMO. It won't make them much louder, but it WILL allow the amp more headroom to handle busy passages, and classical music can be very demanding. The S26s will pull their weight, no question, it's the receiver driving them that will do the clipping if not mated well. You can't base the decision on the power rating, as that can be deceiving. As I have said a number of times here, 100wpc from a Sony DE receiver is not the same as 100wpc from Harmon Kardon (or even Sony ES for that matter [​IMG] ), the H/K will run circles around the Sony DE without breaking a sweat. It is far easier to damage speakers with too little power than too much.
    My recommendation would be to set a target price, and then listen to various receivers in that price range. Try: Marantz, Denon, Harmon Kardon, Sony ES, and Onkyo.
  3. Vince Maskeeper

    Vince Maskeeper Producer

    Jan 18, 1999
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    This would be easier to answer if the wattage rating of most major manufacturers weren't complete and utter lies.

    While what John said above, about amplifier headroom, is entirely accurate and critically important- there is nothing to say that buying an amplifier/receiver that is rated 25 watts higher than another will actually supply this extra headroom!

    Unfortunately, the way wattage is measured varies greatly. Mainly, most amplifiers can be pushed to belch out any extreme amount of wattage, but the signal is greatly distorted... so the question is: "How distorted can a signal become before a manufacturer draws the line and calls that 'maximum wattage'?" Unfortunately, there is no standard.

    Some products will rate their wattage output up to .01% distortion, and call that max. Others run up to .1% distortion or even higher (I've seen one amplifier rate wattage at 1%!!)

    The point is, that one manufacturer's system might rate their product at 75 watts, while another rates itself at 100 watts- yet if tested on an even playing field they might be dead even.

    In the end, the answer is always the same. You can't trust specs- they are often an interesting supplement- however the main concern should be your ears.


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