jwc Posted January 5, 2009 Share Posted January 5, 2009 11 ft ceiling. 1 meter from the floor. There are posts of the 2446 earlier in this thread. Outside......but they don't look as pretty. I went to more than one place outside.......there was always some weird spikes here and there. But they would go away when I moved to another location. I'm gonna take a stab again.....regarding your polars. Yes. There was no intention really with this horn to do polar work. By chance, did better than I thought. On my next one......I have a different goal in mind...the polars might be better...but that isn't my priority. jc Quote Link to comment Share on other sites More sharing options...
DrWho Posted January 5, 2009 Share Posted January 5, 2009 Ah, so 8 feet then, which puts you at 283Hz for two wavelengthsinstead of 230Hz. That's good because it makes more sense that way. Iguess I got to this thread late and missed your earlier plots. For whatit's worth, if the noise floor outside is low, then I would trust theoutdoor plots a lot more than the indoor plots. I haven't spent anytime trying to intrepret them though. Did you share your test setup(mic and boundary locations) for the earlier measurements too? Haveyou ever considered putting your measurement microphone on the floorand then tilting the speaker forward so that the microphone becomes on-axis?This is a great trick for removing tboundary effects of the floor...andif you're close enough, it usually negates the effects of the ceilingtoo. Quote Link to comment Share on other sites More sharing options...
jwc Posted January 5, 2009 Share Posted January 5, 2009 In the past I have done some measurements with the mic on the floor. I believe I tilted some bass bins like what you say. When comparing the outside and the inside curves...the crude polars are similar. The Klipsch K1132 and the JBL 2446 look similar and play down to 400Hz. The JBL 2482 plays down to 300Hz. I'm not concerned about those undulations in my measurements and not feeling pressed to find an explanation. They changed when I moved the setup to other locations. The polars, high cutoff, and low cutoff stayed consistent wherever I went. I'm through with the measurements on this horn for now. I'm now just waiting to hear from people who have or will have the horn to get their "sound" impression. jc Quote Link to comment Share on other sites More sharing options...
Guest David H Posted January 5, 2009 Share Posted January 5, 2009 I have been working on a mount for a Crites CT125 tweeter and the large tractrix horn, here is the prototype. Quote Link to comment Share on other sites More sharing options...
Guest David H Posted January 5, 2009 Share Posted January 5, 2009 Baffle pic Quote Link to comment Share on other sites More sharing options...
Guest David H Posted January 5, 2009 Share Posted January 5, 2009 Rear pic Quote Link to comment Share on other sites More sharing options...
Guest David H Posted January 5, 2009 Share Posted January 5, 2009 Top view Quote Link to comment Share on other sites More sharing options...
Guest David H Posted January 5, 2009 Share Posted January 5, 2009 Front Suggetions welcome. Quote Link to comment Share on other sites More sharing options...
Guest David H Posted January 5, 2009 Share Posted January 5, 2009 Motor board support Quote Link to comment Share on other sites More sharing options...
jwc Posted January 5, 2009 Share Posted January 5, 2009 Holy cow. You are so fast. I have no business building anymore. Just a man left with ideas. What is the total depth of the bottom plate? What is the total height of the tweeter baffle? Is there any "space" below the eminence driver?......almost touching? jc Quote Link to comment Share on other sites More sharing options...
greg928gts Posted January 5, 2009 Share Posted January 5, 2009 Nice work! Greg Quote Link to comment Share on other sites More sharing options...
Guest David H Posted January 5, 2009 Share Posted January 5, 2009 JW is this what you had in mind? I am not thrilled with the look of the front plate, I think it needs something. Greg any Ideas? What is the total depth of the bottom plate? 24.25" What is the total height of the tweeter baffle? Is there any "space" below the eminence driver?......almost touching? The eminance is touching, I need to make a modification. Total height is 4" Quote Link to comment Share on other sites More sharing options...
jwc Posted January 5, 2009 Share Posted January 5, 2009 Well. The baffle of the tweeter is a little taller than I thought. But seems like that the best you can do with the driver height of the Crites tweet. I'm gonna have to think about it. Everything else...I likey. jc Quote Link to comment Share on other sites More sharing options...
Guest David H Posted January 6, 2009 Share Posted January 6, 2009 Actually, I can make the baffle about a .5 inches shorter, by raising the tweeter. There is plenty of room above the motor due to the rake of the horn. I was just trying to center the tweeter. Give it some thought. Did some measuring tonite, I can get the front baffle down to 3 inches and still center a CT-125 or K-77 with plenty of room. All I had to do is router out a recession in the bottom of the horn cradle big enough for the Eminance motor to go in. That may just be whats needed. Quote Link to comment Share on other sites More sharing options...
jwc Posted January 6, 2009 Share Posted January 6, 2009 Good idea. That will look better. jc Quote Link to comment Share on other sites More sharing options...
John Warren Posted January 6, 2009 Share Posted January 6, 2009 Compression drivers suck. There, I said it. Are you ready to accept that it is futile to expect sound "reproduction" from a device design for sound "production"? Quote Link to comment Share on other sites More sharing options...
bodcaw boy Posted January 6, 2009 Share Posted January 6, 2009 that's funny!! 1 Quote Link to comment Share on other sites More sharing options...
Deang Posted January 6, 2009 Share Posted January 6, 2009 I kind of understand what you're saying John, but it seems like hair splitting -- all drivers, whether DR, compression driver or otherwise -- basically just turn electrical energy into mechanical motion. Hey, they use DR's and ribbons for "production" too. When I made the comment I was really just thinking about what a PITA they are to work with. With that said, I do have an observation: A good big horn sounds better than a small one, and though directivity is "controlled", the soundfield is obviously more expansive because of the size of the horn. O.K., so now you have this nice big sweet spot (just like a DR system), but by default, have made the room a much bigger part of the equation (just like a DR system). So, at this point, an argument might be made that says to the effect; if you don't need to fill a big room with obscenely high output, or are running amps that have more than 3 watts -- what do we really need compression drivers and horns for? I know a popular answer will be lower distortion, to which I can only suggest to go out and listen to some good DR systems. Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted January 6, 2009 Share Posted January 6, 2009 Dean, may I suggest headphones? Quote Link to comment Share on other sites More sharing options...
Guest " " Posted January 6, 2009 Share Posted January 6, 2009 "Suggetions welcome." since you asked for suggestions...after you are done with the traditional design tweeter mounting....do another with the tweeter voice coil in line with the mid driver vioce coil...a simple bracket would work fine. Quote Link to comment Share on other sites More sharing options...
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