Rudy81

@Chris A, looking at the GD plot a few posts up, what do you think is causing the slight hump around 1.2kHz? No name xover is set to 700hz. I think if I could flatten that 0.3ms bump, I could straighten out the vertical spectrogram. Figured I'd get this as near perfect as possible.

My schedule changes each month, so just let me know when you are bored and feel like a drive. If I'm in town we can get together.

Don't rub it in @Chris A

This is how that experiment went.

It wasn't that I didn't like it. It had worse performance in the area of interest between 800hz and 2khz. I never even listened to that setup, I was simply going by what REW noted. I will try and find the plot on that so you can see. Edit: I am posting the plot comparing the options I considered. The focus has been on the lower end of the response, and I found the wings only to be the better choice. Also, the full horn is really tall with the top side......it is a large structure, and I know since my Oris are darn large as well. Yes, I am all in now on listening. Looking forward to your results on the extended wings!

Gulp....Oris are now available. Will be listed on USaudiomart in the next few days unless anyone wants them. 😱

I had one more thing to try in my testing plan and that was to move the wings forward so that the AMT drivers would be flush with the front edge of the bass bin. This leaves the wings floating in space, but places the AMT where it normally goes on the ESS speakers. Since active crossing allows me to manipulate the delay, it is easy to move the wings forward. I surmised that with the wings back on the bass bin, the top of the bass bin truncates the sound moving downward from the drivers. After initial setup and EQ, I moved the wings forward and reset the timing to match the 6" forward position. Listening alone makes this an obvious choice. Sound opens up even more and I got a fuller soundstage....the type I originally heard when l first listened to individual AMTs on each speaker. Here are the plot results for the wings forward placement. I think this will be the preferred position for further evaluation. @Thaddeus Smith, when are you coming over? I need another set of ears to critique the setup.

Quick and dirty EQ and 700Hz xover setup. Think I'll start here for some listening and see how it goes. If this works, I'll live with it a bit and hopefully as time goes on we can get our heads together and work on really lowering the xover points. Although, I think as it is you could cross at 500 hz, at least on a graph....not sure how it would sound. If you guys think I'm missing something, please let me know. I will move on to sealing up the wing/AMT interface area....pics to follow.

Chris, I have not been working on the 400hz region simply to expedite getting something up and running that can be used on a daily basis. Once I get this working for daily use, I do plan on exploring other, better options. I would love to be able to cross at 400hz and stay out of the my bass bin resonance point. For now though, I am looking at a 700hz crossover to give the AMT the majority of the sound spectrum. I am more positive every day on what we may be able to achieve with the drivers. Clearly, a type of horn is needed to support the lower frequencies, but it is very doable! One I get the system set and tweaked at 700hz I'll post the results.

For those who may be interested in what the different xover possibilities are, here are xover plots from 300Hz-1kHz on my waveguide setup. Over time, I'm sure better designs can improve on this. I have yet to decide where to cross my setup and fortunately can select a broad range of xover points. These plots were the Stacked AMTs only with my bass bin muted, L/R 24dB slope crossover.

When I did my first prototype work, I started with a full, four sided, horn with my current sides and tops. The SPL results showed some cancellation issues in that configuration. I then took the bottom part off, followed by the top. The only configuration that worked well were just the side wings. I use the same angle on the top and bottom as the sides....that was no bueno. A good horn design for this setup will require someone with good technical know how and a way to manufacture said horn. I think that if we all keep working on this, we may come up with something truly worthwhile for a two way system.

Just a wee bit sensitive aren't we? LOL. I can bring my new toys. There is no way I can bring my bass bin. Took two of us to move each one upstairs. Just barely cleared the width of the stairs....it was nuts moving them. I am about to run sweeps from 1khz down to 400hz with just the AMTs. Hopefully, this will give you guys an idea of what you may be able to do. Plan is to just run the AMT HF so as not to include anything from my LF. For consistency, I will use L/R 24dB slopes. I am curious to see just what they can do at the various crossover points.

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.

Thank you....already on my calendar.

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?

When you cut the tops off, leave an eigth to quarter inch above the bass bin top. Then use a router with a flush bit to trim the excess. Then, your top will be pretty flawless. I used heavy duty spikes from Parts Express for my bass bin bottoms if your floor can handle spikes. The few parts you will need for your 'wings' can be obtained near my house if you don't want to lug stuff over. Paint can always wait 'till you are really happy with the product.....of course, it is all your call.

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.

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....

@Chris A, thank you sir! I have learned a lot from you.

Good choice sir. Here are the results with a 1.3ms HF delay. NO EQ. Getting tired now and will continue tomorrow.

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.

....disregard this post. Just noticed I had a 'leftover' delay in the HF with these plots. I will re-post shortly.

I have been down this road and can tell you that it is a very worthwhile journey. The amount of flexibility you get when active, is amazing.

I can carry his gear. He can handle the livestock.

@Thaddeus Smith, if you are going, we may have to put your AMT/LaScala project on the front burner. Bring it with you!