What would you do? (Sub upgrade question)

Discussion in 'Speakers' started by BobbyMac, Jul 27, 2005.

  1. BobbyMac

    BobbyMac Auditioning

    Joined:
    Jul 27, 2005
    Messages:
    5
    Likes Received:
    0
    Here's my dilemma: After moving to larger home, my twin SVS PC-Ultras no longer give me the output I'm used to. The theater is now located in a second-floor loft that's 14' X 20' but only three walls...the fourth "wall" leads out to the rest of the house. To a sub, we're talking filling up about 28000 cubic feet of woofage. I could buy a couple more Ultras or sell the Ultras and get a couple of PB12-Plus/2s or get a Buttkicker for the sofa.

    What would you guys do?
     
  2. Kenny WH

    Kenny WH Stunt Coordinator

    Joined:
    Jun 27, 2000
    Messages:
    50
    Likes Received:
    0
    Bob,

    Adding two additional Ultra's will give you a couple more db's but I'd first try tactile transducers in you seating.

    I've got a pair of original un-modded ULTRA's and a couple other large subs in my theater and the best bang for the buck was achieved by adding some tactile transducers.

    I'd start by trying the Aura units that can be bought at partsexpress.com for around $30 a pair. Two pair in the frame of a normal couch would be a great start. If you go with the Aura's, I strongly suggest running them off a receiver rather than a standard power amp. The aura's need the signal gain that you get with a receivers preamp section plus it will allow more precise control of the effect.

    I recently put four aura's in my brother-in-law's couch. I ran them off an old sony pro-logic receiver and they work great. He can even control them via remote. They really give an impression of fuller/louder bass. They don't go as deep and are not nearly as powerful as the Buttkickers or even the Clarks. But for such a small amount of money they will let you know if tt's will meet your needs or not.
     
  3. Philip Hamm

    Philip Hamm Lead Actor

    Joined:
    Jan 23, 1999
    Messages:
    6,873
    Likes Received:
    2
    If you have an available space and some basic woodworking skills, there's nothing that beats an infinite baffle arrangement.
     
  4. ColinM

    ColinM Cinematographer

    Joined:
    Dec 9, 2001
    Messages:
    2,050
    Likes Received:
    0
    EQ, IB, transducers, or get some PA bins.

    Or build a better room.

    Or sit back and ask yourself, is this out of control? I mean GEE WHIZ! Twin Ultras, and that's not enough...[​IMG]
     
  5. Arthur S

    Arthur S Cinematographer

    Joined:
    Jul 2, 1999
    Messages:
    2,568
    Likes Received:
    0
    Bob

    Trading in the Ultras for 2 PB12-Plus/2 should give you a substantial boost in output. You should talk to Ron S at SVS for advice.

    Equipment lists are not permitted in signatures.
     
  6. Ryan Schnacke

    Ryan Schnacke Supporting Actor

    Joined:
    Feb 5, 2001
    Messages:
    876
    Likes Received:
    0
    "my twin SVS PC-Ultras no longer give me the output I'm used to."

    This is very vague. No way anybody could reliably determine the problem without much more detail. How did you calibrate your Ultras? Do you know they won't give you enough output? Did you turn them up until the amp gave up (clipping or signal compression) or the woofers bottomed? If not, then you have no reason to believe that you don't have *enough* output.

    Or perhaps, and this seems more likely, you calibrated your subs to the same level as you did in your old house, but the response is much different in this new enviroment. You're obviously going to have different room interactions and its possible that some modes or nulls are causing you to perceive that you need more woofage. But adding more output won't help if the problem is frequency response. You'll just end up calibrating back to where you started.

    Better would be to measure the frequency response at your listening position and then experiment with subwoofer placement and equalization to fix any nasty peaks or dips. Spending $250 on measurement equipment and EQ would be much cheaper than adding additon Ultras. And its a worthy addition to a high-end subwoofer system like this one.

    Room gain is composed of boundary gain (from being adjacent to boundaries) and pressure vessel gain (when the space is too small to contain an entire wavelength of a given frequency). You've lost the pressure vessel gain you had in your old room, but boundary gain can still be significant.

    Sometimes I get the impression that people think if one room is twice as big as another room, then it requires twice as much woofer displacement. This can't possibly be true. This line of logic would say that a subwoofer would not produce ANY sound in an infinitely large space. I've played by SVS on my back porch and I was quite impressed with how much output I got.
     
  7. ColinM

    ColinM Cinematographer

    Joined:
    Dec 9, 2001
    Messages:
    2,050
    Likes Received:
    0
    Good analogy.
     
  8. MikeLi

    MikeLi Supporting Actor

    Joined:
    May 6, 2003
    Messages:
    945
    Likes Received:
    0
    Since you already have SVS subs.. I would call and discuss with Ron like the other poster stated. He will come up with just the right thing for you...
     
  9. Kenny WH

    Kenny WH Stunt Coordinator

    Joined:
    Jun 27, 2000
    Messages:
    50
    Likes Received:
    0
    Bob,

    I agree with what others are saying about placement. I assumed you already had tried different placement. If you haven't then start there. An easy way to experiment(if possible) is by temporarily setting up and running your Ultra's at or as close as possible to your main seating area. Then walk around the room to the areas that you can possibly place the subs and see where you get the best bass response then go from there. All the woofers in the world won't do much for a bad null. My room has a couple bad nulls I've had to work around. If you place a sub in one, the null just seems to suck the bass down a black hole.[​IMG]

    I still think TT's are a viable option for you by giving an increased sense of bass without really adding any more audible sound. Another plus to the tt's is since your doing the system in a loft...you limit the amount of noise overflowing into the rest of your home.
     

Share This Page