Are multiple 8" or 10" subs better than one 12"

Discussion in 'Archived Threads 2001-2004' started by Ryan T, Oct 6, 2001.

  1. Ryan T

    Ryan T Second Unit

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    Hi, today I went to a speaker store to listen to some high quality speakers. While I was there I started talking to one of the sales people about subwoofers, at the time he was showing me a pair of polk speakers, the model number is RT2000i there a powered tower speaker with a 1" dome tweeter, 6 1/2" mid/bass and two 8" subwoofers with 50 watts RMS per tower. Anyway I mentioned that I was going to build a subwoofer with a 12" shiva and he said that his two little 8" subs would sound better than a shiva in a properly designed box because there smaller cone diameter gives then better transient response and 12" subs sound sloppy. Of course I know that a shiva in a properly designed enclosure could blow those little polks right out of the water any day, I could sorta understand what he was trying to say. What do you guys think.
    Ryan
     
  2. John Kotches

    John Kotches Cinematographer

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    I used to think that too.
    A properly designed and executed single driver will have no driver interaction issues to work around.
    The 8" driver will generally have distortion kicking in at a higher frequency and a lower SPL.
    Of course crappy design will destroy any theoretical advantage as well!
    Regards,
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    John Kotches
    Contributing Writer
    Secrets of Home Theater and High Fidelity
     
  3. Jack Gilvey

    Jack Gilvey Producer

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  4. Dan Wesnor

    Dan Wesnor Second Unit

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    I have a Stryke SB-10 (10") in a 45L sealed box that hits 20Hz in room. It's not got the power of my 95L ported Shiva, but it has the same in-room extension, tighter sound, no worries about sub-sonic farting below the tuning frequency, and has a much less intrusive box. The room is huge - about 100sq. ft. w/ 9-10ft ceilings, and one SB-10 is great for music and almost cuts it for even the harshest movies at respectable volumes. When I get the second one finished, the pair will smoke the ported Shiva for output and sound better to boot (but at about 3X the cost) and still won't be as ugly sitting in the room.
    You have to be careful building "uber-subs". There's about 8-10dB of room gain down at 20Hz, and most sub amps have another 6dB gain at 25-30Hz on top of that, and a subsonic filter at about 18Hz. That means the sub's output in the 20-30Hz range is substantially higher than at 40-60Hz, which can be a bit boomy.
     
  5. Jack Gilvey

    Jack Gilvey Producer

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  6. Ryan T

    Ryan T Second Unit

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    I could see if your using a 8" sub with lets say a 20 oz magnet and then a 12" sub with the same magnet, I could understand how the smaller speakers might have better transient response, but if you have a bigger driver then you would also want a bigger magnet and there should be no problem with the transient response because you have a more powerful magnet that can pull or push the cone at the same speed as the smaller speaker right? I mean doesn’t magnet size and cone size balance out to where transient response is not really a problem?
    Ryan
     
  7. Bob Ahlberg

    Bob Ahlberg Agent

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    Ryan...
    You are on the right track. It's more than just magnet size however, it's the material the magnet is made of, the strength of the magnetic field, the compliance of the suspension, the materials used in the voice coil and on and on. The bottom line is that a high quality 12"...or even 15" driver in the proper enclosure will yield very good transient response and impact while providing higher sound presssure levels than a small driver. This is assuming that the xmax of the drivers is at least equal. Often, (not always) the larger driver will have a slightly larger xmax.
    my .02
    Bob
     
  8. Neil Joseph

    Neil Joseph Lead Actor

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    Give me a great 12" sub anyday over 3 great 8 or 10" subs. The multiple smaller subs will go louder but the single bigger sub will go lower. There are very decent 12" drivers that have quick responses and are geat for music.
    ------------------
    http://webhome.idirect.com/~orange1[​IMG]
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  9. MarcS

    MarcS Stunt Coordinator

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    Uh Dan--did you mean your "huge" room is 1000 sq. ft. (not 100)? Did you use a "fisherman's" ruler to measure? Ha ha...
    Now 1000 sq ft IS big--100 sq. ft. is a very small bedroom.......
    [​IMG]
     
  10. James W. Johnson

    James W. Johnson Screenwriter

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    When I went from a dual Shiva to a dual Tempest I noticed quite a difference , the 15" drivers hit the low notes with less effort , this is audible to me. Bass sounds best when the drivers are barely working.
    Now I am looking forward to using some 18"ers [​IMG]
     
  11. Scott Simonian

    Scott Simonian Screenwriter

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    Lucky Bastard [​IMG] @ James.
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    Yes, these are bruises from fighting. Yes, I am comfortable with that. I am enlightened.
     

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