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  • #76
    Re: Project L.O.K.I. Build thread.

    Originally posted by HareBrained View Post
    You could almost get away with stacking 2 of these.
    Wow, no kidding. They're just a bit too small. What Ed's building will be roughly 2.5 cubic feet, and even that seems a bit on the light side of potential vented alignments for the pair.

    But, if sealed were desired, then a pair of those cabinets per side could definitely suffice to build a stack-able set. They'd still need stands though.
    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.

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    • #77
      Re: Project L.O.K.I. Build thread.

      Just ordered one of these for the baffle edge on mine. Might make a nice edge for this design.
      http://www.amazon.com/Extra-Large-Th...d_sim_sbs_hi_5

      Others I had seen run $60-$100

      There are four sizes.

      Comment


      • #78
        Re: Project L.O.K.I. Build thread.

        But, if sealed were desired, then a pair of those cabints per side could definitely suffice to build a stack-able set. They'd still need stands though.
        Would they need stands? If you are sitting 9 feet away and you ear level is 42" high, then your design would be about 4.5 degrees off axis for the tweeter and the pair of PE cabinets would be about 7.5 degrees off the tweeter axis. I think either is reasonable, unless the wave guide for the tweeter makes vertical off axis more offensive.

        Chris
        Chris

        Goofing around since 2000.

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        • #79
          Re: Project L.O.K.I. Build thread.

          Originally posted by czag View Post
          Would they need stands? If you are sitting 9 feet away and you ear level is 42" high, then your design would be about 4.5 degrees off axis for the tweeter and the pair of PE cabinets would be about 7.5 degrees off the tweeter axis. I think either is reasonable, unless the wave guide for the tweeter makes vertical off axis more offensive.

          Chris
          With the tweeter below axis, and the woofer below that, you are pushing the woofer acoustic center farther away, but even so, it should still be well within the lobe formed by the pair at the XO point. Voicing might be a little different with one of the woofers essentially hugging the floor.

          I'd still opt for a stand to get the tweeter closer to listening height. I'm going to set the XO up at 2m with the mic on the tweeter axis, maybe a couple inches lower. The sound will retain the character better when going from seated to standing.

          But on further consideration, I suppose if you put the single woofer as close to the top of the lower cabinet as possible, you might get away without boosting it up a few more inches . . . Still, that tweeter sitting less than 30" off the floor is marginal to me.
          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.

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          • #80
            Re: Project L.O.K.I. Build thread.

            Perhaps one coulld create a tall plinth for the base, maybe a couple inches deep, enough to house the XO, and also put a little angle on the plinth to tilt the baffle back a tad. This would effectively raise the tweeter axis add move the woofer closer while using the standard PE boxes.
            Dan N.

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            • #81
              Re: Project L.O.K.I. Build thread.

              Did I mention, those are going to be some sekci speakers?

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              • #82
                Re: Project L.O.K.I. Build thread.

                OK, some preliminary sims using the measured data I got from the RS28A on the sample baffle Ed sent me, and some traced and modified (Response Modeler) RS225 files. This is aiming for a baseline 89dB, or about 3dB overall BSC. XO is right at 875Hz, LR4, with 4 components on the tweeter, and 6 on the woofer. The breakup hash of the RS225 is over 45dB down. The bass alignment is probably not what I'll finally use, but it's close enough to get a potential crossover going. I'll likely tune the enclosure in the low 30s and not the upper 20s, as shown here.



                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


                • #83
                  Re: Project L.O.K.I. Build thread.

                  Pete,

                  You've mentioned on several occasions that Ed could machine a custom baffle using the RS28 waveguide.

                  Do you think he could do one in a 1 1/2" thick laminated hardwood blank, something like this?

                  https://www.facebook.com/lowecustomguitar

                  www.lowecustomguitars.com

                  Comment


                  • #84
                    Re: Project L.O.K.I. Build thread.

                    The WG needs to be 2" thick. What I normally do is use the W. cut-out for the "donut", epoxying the waste for the extra WG thickness needed. I'm working on a cutter that will make using hardwood possible. As for now the machine I use is just a big pantograph with a router instead of a pencil. It takes literally thousands of cuts to get a WG. I then sand the rough profile smooth. With MDF I can use a little body filler on an errant groove here or there. That isn't possible with a beautiful hardwood blank, so theres some risk involved. Hopefully my new cutter(if its even possible to make!) will make using figured hardwoods possible. I'm in the process of moving, and I had to promise the wife 2 weeks of no speaker involvement. This may kill me after being at AK fest! :D
                    The Past is history. The Future is a mystery. Today is a gift; that's why its called the Present. (Grand Master Oogway, Kung Fu Panda)

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                    • #85
                      Re: Project L.O.K.I. Build thread.

                      Cool!

                      I'm thinking the material I'll end up using will be 1" (actual) thick, so doubling up the woofer cutout could be ideal.

                      I'm still in "what do I want to do for my first project?" mode...:p
                      https://www.facebook.com/lowecustomguitar

                      www.lowecustomguitars.com

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                      • #86
                        Re: Project L.O.K.I. Build thread.

                        Any progress with this build? Was it pushed to the side?

                        Dan

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                        • #87
                          Re: Project L.O.K.I. Build thread.

                          Originally posted by saabracer23 View Post
                          Any progress with this build? Was it pushed to the side?

                          Dan
                          On the back burner at the moment. Everything came to a grinding halt when Ed decided to move his family 30 miles to a new home.

                          Hopefully we'll see a bit of movement after October.

                          I do have a couple of smaller baffles that will only work with a single RS225. It could be adapted to a PE cabinet and make a TM I suppose.

                          I might just have Ed send me his idle pair of RS225-4 and do the straight up 2-way.

                          Thanks for bugging me about this.
                          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


                          • #88
                            Re: Project L.O.K.I. Build thread.

                            On the back burner at the moment. Everything came to a grinding halt when Ed decided to move his family 30 miles to a new home.

                            It could be adapted to a PE cabinet and make a TM I suppose.

                            I might just have Ed send me his idle pair of RS225-4 and do the straight up 2-way.

                            Thanks for bugging me about this.
                            Pete,

                            Just so you know there is interest in this... I had intended to build exactly what you propose. I was have been waiting for D Rose to make a pair to fit the PE cabs but it has been several months. Now that there is another member willing to do CNC work I might go that route. I had been in contact w/ Mark K about updating his RS22528a project with the newer PE drivers and this WG.

                            I have 4 of the original RS225-8's. What I would REALLY like is a design that would allow me to add those to the 2-ways eventually (in seperate boxes). I'll be home from deployment in less than week. I already cut the baffle for the driver and passive radiator for the seperate RS225 while I was on leave. I will probably build my own box for the PE sized baffle shortly after I get back. I need to get the 2-way WG baffle ordered so I have it when I get everything else built. My original plan was to play with this as an active setup until someone comes up with a more permanent crossover design.
                            Thanks,
                            Aaron

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                            • #89
                              Re: Project L.O.K.I. Build thread.

                              Originally posted by aarond View Post
                              Pete,

                              Just so you know there is interest in this... I had intended to build exactly what you propose. I was have been waiting for D Rose to make a pair to fit the PE cabs but it has been several months. Now that there is another member willing to do CNC work I might go that route. I had been in contact w/ Mark K about updating his RS22528a project with the newer PE drivers and this WG.

                              I have 4 of the original RS225-8's. What I would REALLY like is a design that would allow me to add those to the 2-ways eventually (in seperate boxes). I'll be home from deployment in less than week. I already cut the baffle for the driver and passive radiator for the seperate RS225 while I was on leave. I will probably build my own box for the PE sized baffle shortly after I get back. I need to get the 2-way WG baffle ordered so I have it when I get everything else built. My original plan was to play with this as an active setup until someone comes up with a more permanent crossover design.
                              If you can use turned waveguides, I would do two for you free to Pete Schumacher's dimensions, which I used to turn a set of guides for Dave Pellegrene. If I remember correctly(I'll need to check), one of his has a 3.950" radius, which is what was discussed on the Forum a few months ago, and the other radius is minus .125", or 3.825" to accommodate the thickness of the plastic he uses. The jig I built produces uniform cross sections, the outside diameter can be whatever you like up to about 14". The cross section is tangent on about an 8.5" diameter depending upon the thickness and throat opening diameter, and the thickness is about 2.25". I usually make the guides deeper so the back can be milled out using a router to a depth that opens the throat to the appropriate diameter and accommodates the tweeter face plate. Depending upon the material you want, I may be able to give you that as well as the work. I offer because I am curious about the response of these guides and it seems you are likely to provide data upon completion of your project. Let me know if you are interested.

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                              • #90
                                Re: Project L.O.K.I. Build thread.

                                Originally posted by TN Allen View Post
                                I offer because I am curious about the response of these guides and it seems you are likely to provide data upon completion of your project. Let me know if you are interested.
                                TNA,

                                I'd definitely take you up on it if I had the measurement capability. I would also like to get this info out to those that can use it. I was going to foot the freight to Mark K so he could measure and design. I wish I could be more help on this. I'm not sure how tight Pete's time is but I guess could order some baffles from the new CNC source and have them sent to Pete so he could get the ball rolling. Another option might be to have you fab the guides and I could do the rest of the work necessary to build the baffle but that would require 3 people to be involved in shipping/fabricating something instead of just two if I were to get them CNC'd.

                                I'm open to whatever gets the job done. Just tossing out ideas.
                                Thanks,
                                Aaron

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