Announcement

Collapse
No announcement yet.

Car Audio vs Home Theater

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Car Audio vs Home Theater

    What are the differences in car audio subs and a sub for a home theater? Can you use the same driver? I know there is some "cabin gain" (whatever that is) in a car audio installation. Would you use the same size sealed enclosure for a given driver in both instances? Will a "good" car audio sub work well in both cases?

  • #2
    Re: Car Audio vs Home Theater

    Generally speaking drivers designed for cars are designed differently than those for home subs in that:
    Car subs are almost exclusively 4 ohms.
    Cars can be pressurized to some extent and are small enough that cabin gain can be taken into consideration (bonus ). Utilizing smaller sealed cabs often.
    Many car drivers have higher Fs than home subs drivers which are used in larger areas ( that are not pressurized ) with different room acoustics effects.
    "Not a Speaker Designer - Not even on the Internet"
    “Pride is your greatest enemy, humility is your greatest friend.”
    "If the freedom of speech is taken away, then dumb and silent we may be led, like sheep to the slaughter."

    Comment


    • #3
      Re: Car Audio vs Home Theater

      Thanks. So, what do I look for in a sub for a home theater application as far as specs go? Fs range, etc?
      I would think a 4 ohm driver is a plus as long as your amp can push it.

      Comment


      • #4
        Re: Car Audio vs Home Theater

        Carsub/ HTsub. To be honest, their really isn't a difference any longer. I've used subs that were supposedly one or the other with great success. About the only real difference is in appearance. Many car subs have a "bling" factor.

        For me, its really about what you want to accomplish in either enviroment. What enclosure, how much power, placement, etc.

        I tend to favor ported over sealed. Can a sub with a higher Fs be used in the house? YES!! My HT sub at the moment is an 8" Crossfire in a BP enclosure. The Fs is around 40 IIRC and most would say that it can not get low, but Fs is only 1 of the parameters. Others need to be considered also.
        https://www.facebook.com/Mosaic-Audi...7373763888294/

        Comment


        • #5
          Re: Car Audio vs Home Theater

          From Linkwitz:
          "The most important factors to consider in the design of a subwoofer are volume displacement capability of the driver, acceptable cabinet size, and power amplifier requirements. To reproduce low frequencies requires the displacement of large volumes of air to obtain appreciable sound levels."
          http://www.linkwitzlab.com/SPL%20nomographs.htm

          What's in play is something called Hoffman's Iron Law
          "Not a Speaker Designer - Not even on the Internet"
          “Pride is your greatest enemy, humility is your greatest friend.”
          "If the freedom of speech is taken away, then dumb and silent we may be led, like sheep to the slaughter."

          Comment


          • #6
            Re: Car Audio vs Home Theater

            Yep, you can have 2 but 3 isn't possible. We end up with comprimises somewhere. For instance, the sub I finished for a customer last year that wanted 20Hz extension, loads of output, and keep the box small. This is for a car. Taking cabin geometry and actual cabin gain (not a theoritcal number), plus distance from the drivers headrest to the driver and port locations, I desgined a chambered TL. He got 2 of the 3. The box was kinda big even for a single 12. At the headrest, he is able to get about 120db on 600w. Flat and audible down to 15Hz.

            Here's the kicker. The sub used is an Ed 13Ov2. Not a "typical" car sub by its parameters. Most would not even think of using this in a TL of any kind. However, the sub and box were designed specifcally for this car and this owner. Putting this enclosure into another vehicle that is vastly different would not yield the same results.
            https://www.facebook.com/Mosaic-Audi...7373763888294/

            Comment


            • #7
              Re: Car Audio vs Home Theater

              Originally posted by isaeagle4031 View Post
              Carsub/ HTsub. To be honest, their really isn't a difference any longer. I've used subs that were supposedly one or the other with great success. About the only real difference is in appearance. Many car subs have a "bling" factor.

              For me, its really about what you want to accomplish in either enviroment. What enclosure, how much power, placement, etc.

              I tend to favor ported over sealed. Can a sub with a higher Fs be used in the house? YES!! My HT sub at the moment is an 8" Crossfire in a BP enclosure. The Fs is around 40 IIRC and most would say that it can not get low, but Fs is only 1 of the parameters. Others need to be considered also.
              A crossfire fan myself....2 - 10" Crossfire BMF WD10's with Dayton SPA 1000 plate amp..photos attached.. and they rock!!! (if that helps with the original question)
              Attached Files

              Comment


              • #8
                Re: Car Audio vs Home Theater

                So, the same driver could be used in both, but the enclosures would most likely be similar sized or vastly different? In other words, would it be any where close to use the recommended size for auto use in an application for home use?

                Comment


                • #9
                  Re: Car Audio vs Home Theater

                  I dont know much about technical specifications, but I used a 15" cerwin vega hed car sub to build a small sealed down fireing subwoofer for my music system, and power it with on of the 100 watt plate amps and it sounds fine and can really pump out some bass. It easily rattles my whole room.

                  Comment


                  • #10
                    Re: Car Audio vs Home Theater

                    Again: there is a large difference in the internal volume of a car and a living room, so the SPL AND LFE drops quickly.
                    Speakers can be designed for optimum performance in specific applications, or provide acceptable performance in a variety of cabs, but there is no free lunch; compromises are always involved.
                    For many HT means very LF: 20Hz or even lower.
                    As Linkwitz pointed out a fixed law of Physics:
                    For a desired SPL - halving frequency requires 4x the Vd ( either excursion or Sd - 4X the drivers or 4x the excursion from a single driver )
                    So 20Hz requires 4X more air pushed than 40Hz.
                    "Not a Speaker Designer - Not even on the Internet"
                    “Pride is your greatest enemy, humility is your greatest friend.”
                    "If the freedom of speech is taken away, then dumb and silent we may be led, like sheep to the slaughter."

                    Comment


                    • #11
                      Re: Car Audio vs Home Theater

                      Originally posted by isaeagle4031 View Post
                      Here's the kicker. The sub used is an Ed 13Ov2. Not a "typical" car sub by its parameters.
                      I do hope you measured those parameters before designing that TL. I measured the parameters for one that one had locally, and they were off, though not as off as the measured parameters for my 13Kv.2. Qts was around 0.5, if I remember correctly.

                      FWIW, 120dB from a 12" driver in-car not that difficult, even down to 15
                      Hz, and especially if you have 600W on tap.
                      Brian Steele
                      www.diysubwoofers.org

                      Comment


                      • #12
                        Re: Car Audio vs Home Theater

                        Yes, I did measure the T/S numbers. Before break-in and after. After break-in they were fairly close. I don't remember exactly, but they were within my allowable tolerances. I should have noted that the SPL reading (which I post only for others refrences. I don't really care much about them myself) was taken at the headrest and was at 25Hz IIRC. I did not do the measurements on that part. He took it to a local shop that did not believe what he had and they measured. I never said there was a free lunch, I just hate the bad rep that supossed "car subs" get. Some are about being pretty and all, but there are many subs that work well in both enviroments.

                        What is loud to the ear may not be loud to an SPL meter. SPL measures pressure and not actual loudness. Thus when someone says that "by ear" it sounds like x. Db, they are saying that their ear can percieve and interpret sound pressure levels.

                        OP, car subs can be used with ease in the home, Decide on what you want the sub(s) to accomplish in your room and system. Then decide what you can and can not live with. Next look into drivers that others have used and various styles of enclosures. There are those that don't mind having a refrigerator sized enclosure in the room. Others want it to be as small as possible, but still deliver massive amounts of output and extension.

                        There are many "car subs" that work well in small sealed and ported enclosures, but they may need a ton of power to get desired output and extenstion.

                        I'm sure this has probably induced more questions, but that is good. Its how we learn in this hobby. Its late and if this seems a bit incoherent I apoligize. I also hope I don't come off as antagonistic. If I have, I again apoligize.
                        https://www.facebook.com/Mosaic-Audi...7373763888294/

                        Comment


                        • #13
                          Re: Car Audio vs Home Theater

                          Originally posted by isaeagle4031 View Post
                          Yes, I did measure the T/S numbers. Before break-in and after. After break-in they were fairly close.
                          Interesting. I found the measurements I did on the 13Ov2-D4 I got my hands on:

                          Re: 7.256 ohms (coils in series)
                          Fs: 28.26 Hz
                          Qts: 0.4558
                          Qes: 0.4955
                          Le: 3.454 mH

                          These were quite different to the published specs, i.e.

                          Re: 8.3 Ohms
                          Fs: 21.00Hz
                          Qes: .30
                          Qts: .28
                          Qms: 3.3


                          Build quality seemed pretty decent though, given the price for the driver.
                          Brian Steele
                          www.diysubwoofers.org

                          Comment


                          • #14
                            Re: Car Audio vs Home Theater

                            There is really no difference at all between the drivers. Some of the car woofers have stiffer suspensions largely to prevent damage from being over driven. Lets just say the kids don't go easy on their equipment. Beyond that there is next to no difference. The frequency response difference in a car is however very challenging, but has some nice benefits.

                            Here is an article explaining what goes on:

                            http://www.data-bass.com/data?category=review&id=2

                            Comment


                            • #15
                              Re: Car Audio vs Home Theater

                              This is an interesting conversation. I am learning, which is always a plus. I built my first set of speakers in 1973, a few more since. never had anything to measure any specs, so I've always guessed at combinations, and used recommended designs. All surprisingly has been pretty good, some needed tweaking on crossovers and stuff, but came out OK. Home theater is my latest project.

                              Comment

                              Working...
                              X