Announcement

Collapse
No announcement yet.

Chest pounding HT sound

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

  • Chest pounding HT sound

    When I watch movies, nothing gives me that chest pounding feeling that can bring real excitement. I feel the floor shake from my subs but not the pounding. I understand that this comes from a higher frequency than subs are responsible for. My setup is 4 Paradigm Focus speakers (6.5in woofer) and matching center with two RSS390HF subs.

    How is the chest pounding feeling obtained? Do I need bigger woofers in my mains? Would a good MTM work?

  • #2
    Re: Chest pounding HT sound

    Try setting your receiver sub xover to 150hz rather than the normal 80hz. Then apply 12 db (or more) boost at 80-100hz.

    The subs output will become more directional and you won't like the effects for music sources but it will pound.

    Comment


    • #3
      Re: Chest pounding HT sound

      Originally posted by JeffKnob25 View Post
      How is the chest pounding feeling obtained?
      With +110dB levels at the listening position. Few systems are capable of that. These guys will be able to tell you which are:
      http://www.avsforum.com/avs-vb/forumdisplay.php?f=155
      www.billfitzmaurice.com
      www.billfitzmaurice.info/forum

      Comment


      • #4
        Re: Chest pounding HT sound

        How would a line array do toward achieving this goal of mine?

        Comment


        • #5
          Re: Chest pounding HT sound

          Originally posted by billfitzmaurice View Post
          With +110dB levels at the listening position.
          Which requires speakers capable of 135 dB/1M peak calculated SPL at full power. 10dB peak to average ratio, 10dB for path loss (you're not sitting at 1m typically), and 5dB of power compression. As Bill said, that's a tall order. An 87dB/W sub with 200 watts won't cut it, and people seem to think that's capable of 110 dB. It's not.

          Comment


          • #6
            Re: Chest pounding HT sound

            To follow up from what bill said. I will say what he cannot shamelessly plug.;)

            www.billfitzmaurice.com His designs are for EXACTLY what you are looking for. I use 2 of the t-24's coupled together and the slam the dance floor for up to 300 w/o an issue.
            .

            Comment


            • #7
              Re: Chest pounding HT sound

              I bet it's your sub box...
              How did you build it?
              I have one rss390, but I made the box ported at 27-30Hz. In my opinion, anything below that just vibrates stuff. I named it the "bonecrusher" just 'cuz I wanted it to crush bones, not vibrate them at below 20Hz.
              What do you have the subs in?
              I doubt my design is the best, but I'm curious to know your using

              Comment


              • #8
                Re: Chest pounding HT sound

                Which requires speakers capable of 135 dB/1M peak calculated SPL at full power. 10dB peak to average ratio, 10dB for path loss (you're not sitting at 1m typically), and 5dB of power compression. As Bill said, that's a tall order. An 87dB/W sub with 200 watts won't cut it, and people seem to think that's capable of 110 dB. It's not.
                SPL loss estimates are a little exaggerated it seems. A speaker capable of 135dB at 1M is definitely not needed to achieve 110dB at the listening position. In a typical room, first of all, 6dB loss per doubling of distance does not occur - it's closer to 3-4dB loss per doubling of distance. In addition, the room causes an increase(gain) in LF ranges that is variable depending on specific conditions such as speaker placement, room acoustic properties, listening position, etc.. Two high grade/performance 12" drivers using direct radiator cabinets(not horn loaded) with high power amplification can produce SPLs of 110dB+ at the listening position in a standard sized room with ideal speaker placement. Now, a pair of average quality 12" drivers will not achieve this - but I did specify high grade/performance 12" drivers. The highest performance 12" drivers in a pair can produce 115+dB at the listening position. Also, power compression with high performance drivers can be as low as 1dB at full rated thermal capacity. These high performance drivers are costly, however. One can achieve this level of SPL with much lower cost drivers and much less power using horn loaded type cabinet systems of proper design if cost must be kept low and you will accept the substantial size of extended LF horn cabinets.

                However, in addition to pure SPL, the 'chest pounding' feature is also a function of frequency. One ideally should have a LF section that can extend to a minimum of 110Hz for maximum 'chest pounding' feeling. 150Hz would be ideal to ensure maximum tactile feeling. Of course, the room/speaker interface also must have a relatively good response in this frequency range without substantial cancellation(s). Substantial wide nulls will cause loss of this tactile feeling if they reside in the critical bandwidth in which this feeling occurs. Special considerations need to be made in order to have high fidelity reproduction using subwoofers into the 110-150Hz range such as special high bandwidth acoustic damping materials inside relatively large dimension cabinets and the need to use twin cabinets(one a few feet within each main left and right speaker) to keep seamless integration for music reproduction. Proper active crossovers MUST be used to high pass the main speakers to reduce their work load and keep distortion low. The still in use practice of letting the main speakers roll off naturally is just a bad idea and will result in performance reduction at moderate to higher SPL conditions. In some cases, it even degrades system performance at relatively low SPLs. Most receivers will not have ideal active crossovers due to their technical limitations. Ideally, a proper external active crossover with suitable features is recommended, though I realize it can be impossible to use one in many cases due to the very limited options for external line level hardware that most surround receivers impose. Just another reason to use a surround receiver as the pre-amp processor only and use external amplification(plus you get more power and load stability using external amplifiers). With the external amplifiers, you can easily insert any type of processing hardware you require between the pre-amp outs and line level inputs on the amplifiers. In addition, if you have any level of electronics circuit knowledge, you could install bypass in/out jacks on a surround receiver so that one can insert external processing between the pre-amp stage and amplifier stage and retain full use of the receivers internal pre-amp and source selection and other internal features.

                -Chris

                Comment


                • #9
                  Re: Chest pounding HT sound

                  You need more volume in the 100-150 hz region, and an utter disregard for your hearing in 10 years. :rolleyes:

                  Comment


                  • #10
                    Re: Chest pounding HT sound

                    Originally posted by JeffKnob25 View Post
                    How would a line array do toward achieving this goal of mine?
                    All the posts hint at a tidbit of information for your question and they're right.
                    Here's the breakdown.
                    Chest cavity resonance is around 80 hz. Depending on lung capacity.
                    Actually it starts around 60 hz. Discoes have they're subs and equalizers to heighten 50 hz.
                    There are harmonics involved. i.e 60 - 120 - 240 - 480 hz all the way up to 20k - so good crossovers are in order.
                    The room comes into play and for bass it's cabin gain (bass boom or mud) mids and treble bouncing off the walls ( cancelling or boosting certain frequencys.
                    Line arrays reduce floor and ceiling reflections and their height creates an area sound vs. a point source. More info and explanation can be found in Griffins White Paper.
                    Small drivers with hard cones (bending, flexing) in a line are necessary.


                    Comment


                    • #11
                      Re: Chest pounding HT sound

                      I am getting the impression that chest pounding HT sound is not normal and is maybe an unreasonable goal. I just remember when I was a teenager, I had a pair of 4 way speakers with a 12" woofer and I could really feel them pound. I am thinking that if I want this feeling for my HT I need to have a set of main speakers with the ability to achieve a higher spl in the 100-200Hz range. My 6.5's in my Paradigms won't do it which is understandable. I know I don't want to go back to a 12" woofer so would a line array or a system with multiple woofers be able to achieve similar results as the 12".

                      BTW, to answer a previous question, my two RSS390HF subs are each in a 3ft^3 box with 240W each. I know this is a small box and is under powered. I was given the suggestion to add aperiodic vents and also to get an amp to feed more like 500W to each. It was suggested that I increase the LFE crossover to 150. My receiver, Onkyo 606, will only go to 120 but I am still concerned about the directionality this will present with such a high crossover point.

                      Comment


                      • #12
                        Re: Chest pounding HT sound

                        Originally posted by JeffKnob25 View Post
                        I am getting the impression that chest pounding HT sound is not normal and is maybe an unreasonable goal.
                        HuH!!! :eek:

                        I just remember when I was a teenager, I had a pair of 4 way speakers with a 12" woofer and I could really feel them pound.
                        Probably tuned for that 80 hz thump common during that time.

                        I am thinking that if I want this feeling for my HT I need to have a set of main speakers with the ability to achieve a higher spl in the 100-200Hz range.
                        This was the design goal of BaryBass. I duplicated this design using my Schumakubins and an equalizer and bumping the frequencys at 60, 120, 240, 480, 960...

                        My 6.5's in my Paradigms won't do it which is understandable. I know I don't want to go back to a 12" woofer so would a line array or a system with multiple woofers be able to achieve similar results as the 12".
                        YES... You'll also get rid of that 200-250 hz dip caused by floor bounce. :D

                        Comment


                        • #13
                          Re: Chest pounding HT sound

                          Have you attempted varying the phase of the sub? You may be getting a null at the crossover point due to improper phase.

                          I'm using a pair of RSS315 12" subs as "woofers" in a 3-way, crossed at 300Hz (PASSIVELY I should add). There is no lack of chest-cavity-thump capability.
                          R = h/(2*pi*m*c) and don't you forget it! || Periodic Table as redrawn by Marshall Freerks and Ignatius Schumacher || King Crimson Radio
                          Byzantium Project & Build Thread || MiniByzy Build Thread || 3 x Peerless 850439 HDS 3-way || 8" 2-way - RS28A/B&C8BG51

                          95% of Climate Models Agree: The Observations Must be Wrong
                          "Gravitational systems are the ashes of prior electrical systems.". - Hannes Alfven, Nobel Laureate, Plasma physicist.

                          Comment


                          • #14
                            Re: Chest pounding HT sound

                            Have you attempted varying the phase of the sub? You may be getting a null at the crossover point due to improper phase.

                            I'm using a pair of RSS315 12" subs as "woofers" in a 3-way, crossed at 300Hz (PASSIVELY I should add). There is no lack of chest-cavity-thump capability.
                            Something Darren Kuzma tried to explain here;
                            Re: Woofer

                            Posted By: DarrenK <[email protected]>
                            Date: Thursday, 7 February 2008, at 4:08 p.m.

                            In Response To: Woofer (Eric Jones)

                            From my experience, "punch" when talking about bass response is almost always talking about output in the 60 - 80 Hz range, as Rudy pointed out. I would contend that it is in this 60 Hz sense that most people use the term "punch".(sometimes you hear "slam" too)

                            Either way, it is indeed very difficult to get this "punch" out of a normal home theater sub, especially in a setup like you have. You need to be able to move significant amounts of air at 60 - 80 Hz, which neither of your current speakers or sub can do. Most likely your current sub is totally clipping the amp or operating in high distortion most of the time, which gives it an even more muddy, vibratey sort of sound. You've got a big room to deal with!

                            You can try a sub with a higher crossover point, but you're still limited in surface area, and it'll hard to get the sub to blend with the mains.

                            You can try, and I hope it works, but I'm afraid any sub isn't going to give you that "slam" that you may be looking for. Some mains with dual 10's or dual 12's might do the trick!!!

                            Good luck!

                            Darren

                            Comment


                            • #15
                              Re: Chest pounding HT sound

                              Have you attempted varying the phase of the sub? You may be getting a null at the crossover point due to improper phase.

                              I'm using a pair of RSS315 12" subs as "woofers" in a 3-way, crossed at 300Hz (PASSIVELY I should add). There is no lack of chest-cavity-thump capability.
                              I have never known what to do with the phase so I have left it untouched. Is the sort of setting where I should play a tone and see how the sound changes in my listening position.

                              Comment

                              Working...
                              X