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Which is louder Bi-amped 205watts or 450watts@4ohms?

Discussion in 'Amps and Cabs [BG]' started by trashman34, Dec 2, 2005.


  1. trashman34

    trashman34

    Dec 2, 2005
    My current Rig is an Ampeg B2re (250w@8ohms or 450w@4ohms)w/ because I live upstairs 1-SVT115(200w.RMS@8ohms) 1-SVT210 (also 200w.RMS@8ohms).My problem is I feel the B2re doesn't have enough "overhead". My salesperson whats to give me full credit towards the 1000watt.Stereo B4r.(rated 205w.@8ohms X2 or 700w.bridged, 340w@4ohms X2 or 1000w.Bridged@4ohms) My question is will I be gaining anything? The B4r seems to be massive over the B2r But is a watt a watt? Which is louder the B4r(205watts@8ohms)(x2), or B2re(450watts@4ohms)?
    Wattage wise my existing is louder or... I run 1000watts bridged@4ohms? Please respond... Thanks Trashman
     
  2. tadawson

    tadawson

    Aug 24, 2005
    Lewisville, TX
    A watt is a watt . . . . the impedance (ohm rating) simply determines how much an amp can give a cabinet, but does not have any effect on volume. IE 200 watts into a 2 ohm load, a 4 ohm load or an 8 ohm load will have the same exact output, assuming identical cabinets and drivers with the same efficiency.
    But remember, that doubling the power will only give you 3db more. so while the the biiger head may give more level, you will also be exceeding the ratings of your cabs if you push it, and may well get into power compression, and see no noticeable gain in level. (I am assuming that you would run the B4r bridged into 4 ohms for 1000 watts out, vs, the 450 of the B2re.)

    - Tim
     
  3. billfitzmaurice

    billfitzmaurice Commercial User

    Sep 15, 2004
    New Hampshire
    Owner, Bill Fitzmaurice Loudspeaker Design
    205 @ 8 x 2 is 410 @8 and would be perhaps 2dB louder than 250w@8. That 2dB would be about the equivalent of turning up the volume from 7 to 8. But by running a 1x15 and a 2x10 off the same amp channel you're wasting half the power going to the 1x15 with highs it can't use and half the power going to the 2x10 with lows they can't use. Get the dual channel amp but only if it has a crossover so that each of your cab can be efficiently driven.
     
  4. cb56

    cb56

    Jul 2, 2000
    Central Illinois
    I had that setup at one time. It sounded great! My 50 year old back just couldn't handle it anymore. If you run the B4r bridged into both cabs. 500 watts into each cab, you will never again feel like you are lacking headroom. IMO the better rig was the B4r bridged into a 610hlf. But since you already have the 410/15 setup, I'd say go for it.
     
  5. trashman34

    trashman34

    Dec 2, 2005
    So the B4r seems to be a good upgrade provided I am Bridging the 1000watts at 4 ohms. My salesperson seems to think that even the 205watts at 8ohms is still an upgrade.Also how dangerous is the 500watts going into my 200watts rated cabs.
     
  6. billfitzmaurice

    billfitzmaurice Commercial User

    Sep 15, 2004
    New Hampshire
    Owner, Bill Fitzmaurice Loudspeaker Design
    No. If you do so you're only a bit over 3db better off than now. You're wasting at least that much by running both cabs together. You'll get at least 6dB more if each power amp drives its own speaker and a crossover is employed so that each speaker is actually able to use all the power going into it.
     
  7. cb56

    cb56

    Jul 2, 2000
    Central Illinois
    There you go. The B4r is capable of doing both since it has a built in crossover. That way you can try it out both ways and see which you like best. I did when I owned mine and decided on bridged full range through both cabs.
    You may decide differently as billfitzmaurice did.
     
  8. billfitzmaurice

    billfitzmaurice Commercial User

    Sep 15, 2004
    New Hampshire
    Owner, Bill Fitzmaurice Loudspeaker Design
    If that's the case you can't lose, you've got the option of going either way.
     
  9. trashman34

    trashman34

    Dec 2, 2005
    Thank's for the info guys, Don't know what I'd do without you. Looked closer at the B4r and saw he Bi-amp crossover,had no idea the importance of it. Also thanks for the thoughts of both options are open to me .Much appreciated -Trashman