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  • Will the Statements be enough?

    So I'm thinking about building the Full Size Statement's as my mains, the Statement Center and either the Statement Monitors or Mini's for my surrounds (totaling a 7 channel system). However I'm concerned that the Statements will not be able to keep up with the reference levels (106db) I want to achieve with my home theater (house to be built spring 2011). I'm also wondering how the Monitor's or Mini's will do as surrounds considering their placement; I don't want to be able to audibly locate them if possible and have been told by a few seasoned HT veteran's that since they are direct radiator's they will be easily located and are not suited for this application...

    I'm planning on building a 4x15" IB subwoofer array using AE-IB15's powered by a Behringer EP2500 to handle the lows which will hit the 106db mark with ease and hopefully flat down to 10Hz.

    Should I be looking into a different DIY speaker set for this system? Below is the room layout and section cut thru the middle. How do I calculate the db level at the listener's ears for a given speaker, distance and supplied wattage?




  • #2
    Re: Will the Statements be enough?

    I doubt that you'd not be able to easily reach those SPLs at your seat during movies.

    However, your placement of the side speakers isn't going to work for the statements, as their open back mids need more room behind them to work properly.

    Also, consider turning the seating platform into a sub enclosure. Placing them closer to the seats will certainly help in creating a visceral effect.




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    • #3
      Re: Will the Statements be enough?

      106 dB? I guess if you want the system to reproduce transients at that level cleanly, then your question is legitimate. If, however, you want consistent, extended listening at that level, then I have to say, ARE YOU INSANE????:eek::eek:

      You will quickly go deaf listening at that SPL consistently.

      I'd think the Statements would keep up though, subject to Pete's qualifier about the space from the back wall.


      Mark
      You go your way, I'll go mine. I don't care if we get there on time.

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      • #4
        Re: Will the Statements be enough?

        Looking at the layout, don't you think the center of where all the speakers aim should be dead center of the rear sofa? My father is an architect and it bothers me when he doesn't consider these things. If most of the time it's you watching movies it doesn't matter, but if you have a big family, or often have friends over, only the front row gets all the goods. If you pick the middle of the seating arrangement, everyone gets a taste. Also, make sure you don't build anything permanent for your equipment... it's a common mistake that really limits your options when technology has changed. I.E. If you want to install a projector, but your TV is build into the wall, that could be a whole new renovation. Other than that, I'm sure I'll be jealous of your setup; It sure seems like you aren't going to settle for anything mediocre. Good luck!

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        • #5
          Re: Will the Statements be enough?

          Not only that, but the speakers need toe-in to hit where he wants anyway. He has them aiming off-ais, and that is not going to cut the mustard.

          The side surrounds need to be directly to the side of the listener, not in front of or behind, and the middle row is where I'd put them.

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          Wolf
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          • #6
            Re: Will the Statements be enough?

            Pete:
            <I doubt that you'd not be able to easily reach those SPLs at your seat during movies.>
            I'm sure I could probably hit that mark with the Statements but I'm concerned primarily about the ribbon tweeter not ripping itself apart during these, albeit short blips. Curt states that they will be able to hit a max SPL of 104dB, but at what distance? I've been seeing 1m as a typical distance but want confirmation...

            <However, your placement of the side speakers isn't going to work for the statements, as their open back mids need more room behind them to work properly.>
            I'm struggling with how to handle the location/design of the side speakers.
            Here is a copy/paste of Curt's description on placement for the entire Statement line-up:
            <All of the Statements series designs are to be listened to off axis and positioned pointing straight ahead with 1'-6" of distance from the back of the speaker to the wall behind them. They will work surprisingly well closer but further out is better. The Monitors have gone a step further. Curt waved his magic wand and created (thru crossover adjustments) not only a far wall version that is designed to be used out into the room but also a near wall version that can be used as close as 12"standing at the listening position.

            Vertical positioning (copy/paste from Curt's site):

            Full Statements: <The ribbon height should match the builders seated ear height and can be adjusted to what ever height needed.>

            Mini's: <It's important to have the seated ear height correspond with the area
            between the W4 mid and the ribbon for best sound quality. The W4 carries much of the vocal range and nearly all of the midrange harmonics so positioning is important to have this at ear height.> However since they will be used as surrounds, should I raise them to the standing ear height?

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            • #7
              Re: Will the Statements be enough?

              How does one figure out the achievable dB levels of a speaker if they know the speaker's spec's (i.e. sensitivity), the wattage/impedance supplied (RMS) and the listening position distance (time decay)?

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              • #8
                Re: Will the Statements be enough?

                Your asessment of Curt's statements regarding his statements () is well taken, let me offer a suggestion. Many listeners and designers will toe-in the speakers not to put them on axis, but cross fire them in FRONT of the listening position. This gets you on the intended lobe pattern and puts the nearer speaker more off axis than the far speaker, which tends to equalize volume levels across a wider area.
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                • #9
                  Re: Will the Statements be enough?

                  Thanks Biff. Speaker placement can be handled once the construction side of this theater is complete. I plan on getting as close as I can to where they will be and provide a layer of 5/8" plywood blocking within the wall (replacing that specific locations inner layer of 5/8" drywall) so that I have some flexibility on placement. I need to determine if these speakers will perform they way I want them to given my room design or if I should be looking into a different DIY speaker design for the surrounds since I don't want to easily locate them audibly. I'm still sticking to using the Statement LCR's but need to figure out how much wattage I'll need to supply them given my listening distance...

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                  • #10
                    Re: Will the Statements be enough?

                    This may be "much ado about nothing". If the speakers you're considering are so directional that only one seat position will have good sound, you're looking at the wrong speakers.

                    I'm not suggesting that is the case with the Statements. While they may be a little sensitive to rear wall placement due to dipole mids, I haven't found the Statements to be particularly overly directional.

                    Toe in the mains a little and place the LR surrounds adjacent to the mid row and you should be fine.

                    I too am intrigued by an IB sub system. I will likely try it sometime. In building mine, I had the option for an IB system (still do) but opted for 4 free standing enclosures. I find that dealing with room modes is easier with placement flexibility rather than with room treatments.

                    I ran 4 pairs of sub speaker cable all the way around the room, about 12" off the floor and loosly tacked to the studs. I can cut a hole, add a outlet box and move the subs nearly anywhere in the room.

                    For future flexiblity, I ran 2" DWV PVC conduit from the equipment rack to the front, rear, both sides, under the middle seating row and the projector location. Oh, and also to the lighting circuits. I should be ready for anything that comes along.

                    Designing a dedicated HT room can be challenge but really fun. Don't forget about remote lighting controls and wire for IR targets under the screen for Wii and xbox controls.

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                    • #11
                      Re: Will the Statements be enough?

                      Originally posted by acex008 View Post
                      How does one figure out the achievable dB levels of a speaker if they know the speaker's spec's (i.e. sensitivity), the wattage/impedance supplied (RMS) and the listening position distance (time decay)?
                      Okay. Sensitivity is usually measured at 1 meter. If sensitivity is 86 dB with 1 watt at 1 meter, to get to 106 dB at 1 meter will require 20 dB more power, or 100 watts (96 dB would take 10 watts, 116 dB would require 1000 watts!!!). Then figure on a 6 dB loss for every doubling of distance, 106 dB at 1 meter would be 100 at 2 meters, and 94 at 4 meters. Note that this is due to spherical spreading, not time decay. The area of a sphere is 4 pi R^2, so the area that the pressure wave is going through is proportional to the square of the distance. There are other factors as well, such as wavelength dependent energy absorption.
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                      • #12
                        Re: Will the Statements be enough?

                        Thanks for the sage advice dwigle! You're the first to give me some direct feedback on the Statement's in all the forums I've posted this design! So again thank you for be specific. I'm going to reassess my IB design and probably incorporate an AT screen so I can get that center channel where it should be and originally was...

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                        • #13
                          Re: Will the Statements be enough?

                          start with the sensitivity @ 1W/1m. each doubling of wattage will yield 3db. for each additional meter of distance, subtract either 3 or 6 db (can't remember which... can someone chime in here?). also, keep in mind that that 104db max figure is probably per speaker, whereas, the ~105db reference level you calibrate for/are trying to achieve is, if i'm not mistaken, a total level. when you double cone surface area (eg. 2 speakers as opposed to 1, or 4 as opposed to 2), you get a 3db gain (again, can someone confirm?).

                          your placements look about right to me. dolby and thx both say surrounds can be anywhere from next to you, to a little behind you (actual numbers vary depending on which spec you're looking at, and whether or not you have surround backs). when you've got multiple rows, unless you're running a pair of surrounds next to each row, you're going to have to make a compromise. its pretty common to place the surrounds in a location that might be slightly in front of some rows, in order to not have too much compromise to the primary row.

                          as for your targeted sweet spot, it's yet another personal choice/compromise situation. if you target a spot designed to sacrifice less for the middle row, you will definitely be sacrificing more in terms of the front row. will it make a tangible difference to either row? who knows. lots and lots of variables will play into that. personally, given what you've said about your situation, and my preferences, i'd stick with what you've got. my situation is similar: dedicated two row theater, majority of the use is just the GF and i, but occasionally friends will join. i choose to set mine up with my specific row/seat as the intended sweet spot. i paid for it, i use it the most, and i'm the one whos the most critical of it... therefore i want the best all for me me me :D. also, something to keep in mind is that if you get a receiver with one of the more advanced audyssey suites or other room correction software, it will take measurements all over the place and attempt to create an "acoustic bubble" (another set of compromises, just a VERY advanced set), which will somewhat negate small changes to the targeted sweet spot.

                          EDIT: i type too slow. dwigle and mattk hadn't posted yet when i started this reply. it's each doubling of distance, not each additional meter?

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                          • #14
                            Re: Will the Statements be enough?

                            Matt: Thanks for making that clear, I couldn't get a good concise resource to explain it that way.

                            So let me get this straight, if my speakers are at 4m from the listening position and I want to achieve 106dB and the speakers I choose have an 86dB sensitivity then I will need to provide each of them with over 1000W!!!!?!?!

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                            • #15
                              Re: Will the Statements be enough?

                              The Statements are not a good choice for that HT room. You will limted yourself with that choice.

                              You will require speaker designs that have a better power response, higher SPL peaks and higher sensitivity.

                              Think JBL, Danley, Seaton, JTR, Geddes type designs. Think Zilch/Pete S. Econowave builds!!! Yes, you can not get real performance in that room without horn/waveguide designs.

                              btw, Very nice and BIG room.

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