Chris A Posted January 13, 2020 Author Share Posted January 13, 2020 8 minutes ago, dkalsi said: Whats the vertical dispersion limits on the AMTs? As long as you can get the AMT-1s at ear height or within ~15 degrees, you're in good shape. Double height AMT-1s does help with the vertical coverage. Like any line array type radiator, the vertical dispersion is basically the height of the array ±15 degrees. Chris Link to comment Share on other sites More sharing options...
Rudy81 Posted January 13, 2020 Share Posted January 13, 2020 ....disregard this post. Just noticed I had a 'leftover' delay in the HF with these plots. I will re-post shortly. Link to comment Share on other sites More sharing options...
Rudy81 Posted January 13, 2020 Share Posted January 13, 2020 Ok, here are the results with no timing set, no EQ. AMT diaphragms are about 7.5" from the front of the LF bass bin edge. Bass bin contains two Kappalite 3015LF drivers. Mic was 21" from the AMT diaphragms. At 3 feet, I got some anomaly showing at 4kHz in the GD plot. I know from earlier plots that the stacked AMTs are totally flat in the GD plot, so moved the mic. I suspect there is some room interaction at 3 feet causing the plot variance. EDIT: my apologies. While working on the timing, I realized I had the HF inverted when I took the baseline reading. The jetlag is showing. The newly posted images should be correct. 1 Link to comment Share on other sites More sharing options...
dkalsi Posted January 13, 2020 Share Posted January 13, 2020 Damn you, Rudy! Order placed! 1 1 Link to comment Share on other sites More sharing options...
Rudy81 Posted January 13, 2020 Share Posted January 13, 2020 5 minutes ago, dkalsi said: Damn you, Rudy! Order placed! Good choice sir. Here are the results with a 1.3ms HF delay. NO EQ. Getting tired now and will continue tomorrow. 1 Link to comment Share on other sites More sharing options...
Rudy81 Posted January 13, 2020 Share Posted January 13, 2020 @Chris A, thank you sir! I have learned a lot from you. 1 Link to comment Share on other sites More sharing options...
ClaudeJ1 Posted January 13, 2020 Share Posted January 13, 2020 15 minutes ago, Rudy81 said: Bass bin contains two Kappalite 3015LF drivers. Is your bass bin Reflex? Link to comment Share on other sites More sharing options...
Rudy81 Posted January 13, 2020 Share Posted January 13, 2020 28 minutes ago, ClaudeJ1 said: Is your bass bin Reflex? Yes sir. It is approximately 12 cu. ft., with a 25hz tuning point. I had a lot of help in that build as well as my four 18" full marty subs. I need to stiffen my bass bins just a bit and will be working on that later this week. Plan is to add vinyl tiles to the interior and also open cell foam to contain some problem resonances I have noticed.... Link to comment Share on other sites More sharing options...
Rudy81 Posted January 13, 2020 Share Posted January 13, 2020 SPL comparison with no delay and no EQ, vs. with 1.3ms delay and no EQ. EQ will begin tomorrow when I have two brain cells to rub together. I will be working first on modifying my no name xover to flatten the area around 900hz. I suspect that can easily be done by messing with the xover points. Then some minor EQ and I should be in business. I must confess that I am more excited about the prospect of this project today than I was even before....and I was pretty darn excited about it. 1 Link to comment Share on other sites More sharing options...
Rudy81 Posted January 13, 2020 Share Posted January 13, 2020 1 hour ago, dkalsi said: Whats the vertical dispersion limits on the AMTs? Rudy's got me interested in the AMTs - but I'd be looking for a simple 2-way with a 12" (mini Heresy) or perhaps with a 15" JBL 2226H. Don't worry about the vertical dispersion if you are going to use the speakers for enjoying music from a seated, relatively constant location. IMHO, a good LF box will be needed. The AMT is so dang capable, it will challenge your bass section. I am assuming you will be going active for the xover. Are you building your own LF section? Link to comment Share on other sites More sharing options...
Delicious2 Posted January 13, 2020 Share Posted January 13, 2020 I had some rough tops I had cut when I had K402s on top of my Khorn bass bins. Thought they would make a serviceable base for this test rig(s). 2 Link to comment Share on other sites More sharing options...
Delicious2 Posted January 13, 2020 Share Posted January 13, 2020 No wings "control" 2 Link to comment Share on other sites More sharing options...
Delicious2 Posted January 13, 2020 Share Posted January 13, 2020 1 wing set 2 Link to comment Share on other sites More sharing options...
Delicious2 Posted January 13, 2020 Share Posted January 13, 2020 HInged some together. 2 wing set. 2 Link to comment Share on other sites More sharing options...
Delicious2 Posted January 13, 2020 Share Posted January 13, 2020 3 wings right. 2 Link to comment Share on other sites More sharing options...
No.4 Posted January 13, 2020 Share Posted January 13, 2020 @Delicious2 very cool! Link to comment Share on other sites More sharing options...
Schu Posted January 13, 2020 Share Posted January 13, 2020 Can I ask... and perhaps it's already been discussed somewhere in the thread, would a curved face/lens be an option? Link to comment Share on other sites More sharing options...
Rudy81 Posted January 13, 2020 Share Posted January 13, 2020 1 hour ago, Schu said: Can I ask... and perhaps it's already been discussed somewhere in the thread, would a curved face/lens be an option? I'm sure it would be an option and may even perform better if properly designed. Having built several curved horns, I went for the quick and easy. At least for me, building a curved horn is complicated and takes a lot of time. I don't have enough expertise to model one before building, so it would be trial and error all the way. I just don't have the time to go down that road. I would love to have the SPL plots for the curved horn that Hawthorne Audio built or the prototype the ESS has. Link to comment Share on other sites More sharing options...
No.4 Posted January 13, 2020 Share Posted January 13, 2020 1 hour ago, Schu said: Can I ask... and perhaps it's already been discussed somewhere in the thread, would a curved face/lens be an option? When I get my measurement setup dialed in on the straight face lenses, I am planning on experimenting with a curve. it may take a little while. Link to comment Share on other sites More sharing options...
Tarheel TJ Posted January 13, 2020 Share Posted January 13, 2020 Chris, I am definitely interested in seeing what you can do with a Heil/MEH design. My first thought when I saw this was "how can I turn this into an MEH arrangement?" It seems like it would have incredible potential! 1 Link to comment Share on other sites More sharing options...
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