Rudy81

Done!

Looks like all the cool kids are going to attend, can I come too?

I may have to take time off for that. @Chris A, if you will be there giving lessons, I'm attending!

You would be welcome any time. What is this SWAG thing? If it is a public venue, e-mail me info please.

For those of you who have taken the leap and ordered AMTs, but are now wondering if this is worth it.....the answer is an unequivocal yes! Press on. I created the no-name crossovers at 1khz, two way and mimicked a 24dB/oct L/R crossover. Set up a L/R crossover on one channel and used the graphic function to mimic the slope on another channel. Took two EQ slots on the Xilica, one is a -30dB shelf and then used one EQ to shape the slope. Below is an example. After setting up both channels and I just couldn't stand it, so decided to jump right into listening. Did not EQ, did not set timing, just set the xover and turned them on. This is most definitely going to work for me. Even without tweaking and optimizing the HF/LF timing and EQ....it sounds really, really good to my ears. I still get blown away by the expansiveness and accuracy of the sound stage. Vocals sound excellent, so mid-range is not a problem. If I do have any issues at the crossover region, I will simply use a gentler slope on my bass bins to fill any missing parts....but I don't think that will be necessary. When I run sweeps, we will see how it looks technically. I am very happy with this project thus far. Seems to me it can only get better and I like the way it sounds right now. Current plan onward is to fine tune the system. First, add the clay and finish the wing structure properly. Then set the timing and EQ at 1kHz as a baseline for normal use as a starting point. Then, I will start experimenting with lower crossover points until I find the sweetspot for my HF/LF combination. Sensei, @Chris A, you will have to venture north for a listen some time. Lunch will be on me.

The Oris are the only ones complaining now. Time to setup the xovers. Plan is for No xover, use the Danley style that @Chris A taught me. I'm going to start calling Chris, Sensei.

Before top is added.

Some close ups so you can see how I put it all together. Details on little tweaks to follow. Build note: I added very thin black tape insulation to the top end of the waveguide. I did not want the top to vibrate and possibly cause problems, so the tape should prevent any vibration. Decided to place the barrier strip on the side to keep the wires away from the back of the drivers and out of view from the center of the room. Wiring is somewhat temporary for now. Placed the entire platform on vibration isolation pucks to again prevent vibrations from bass bin affecting the AMTs. Not sure if that is even necessary, but doing the best I can to optimize what the AMTs can do. Suggestions are welcome!

Been waiting seems like forever for today to get here: Not totally finished, but ready to begin testing. Still need to trim the rod length for that finished look and need to add black clay to smooth out the driver to waveguide transition. Now on to work on the other channel. Then, set up xovers, then run some sweeps to show what the whole speaker will do and on to the best part.....listening challenge!

Nice testing platform. Let us know your measurements. Interesting concept.

Yes, that is the location that I plan on filling with some material to keep a smooth surface. I don't think I need to hermetically seal the area, just smooth it out a bit.

Great! You have a sound plan. Forge ahead sir. Call on me if you need anything. I'm no expert, but I have been in your shoes.

Yep, that should work just fine...in theory. Biggest hurdle is getting good signal quality between the RCA outs from your AVR to the Yamaha inputs in XLR and then reversed again when you go from the Yamaha to the ATI amp, unless it has XLR inputs. When I started doing what you are doing, the problem that often comes up is that mixing consumer electronics with pro gear CAN, at times, cause problems due to the different voltage 'standards' of the signals in questions. This subject gets really complex and addresses gain structure. You should read this when you have time: https://www.hometheatershack.com/threads/gain-structure-for-home-theater-getting-the-most-from-pro-audio-equipment-in-your-system.35677/#post-317665 IF any of the units you will be using have a high noise floor, you might be able to hear that noise in your speakers....and you are not going to like that. I ran into that early on. The only way to know is to plow ahead and try it out. In no way am I trying to dampen your spirit in the project, just letting you know some hurdles may be ahead. BUT!, the effort will be worth it! BTW, did you already acquire the Yamaha?

Before we go too far down this trail, I looked at the AVR-X3400H. Can you tell me how you plan on hooking all this up? Are you going to have separate amps for the mains and subs? Are you going to just use the pre-amp section of the AVR for the mains etc? I'm trying to get a picture of how you will be setting this up.

You will likely have to do some experimenting to find out just exactly what your AVR does. My opinion is that if you leave out the LFE, the LFE signal will NOT be sent to the mains. My understanding is that channel is strictly for a subwoofer, not a main. I understand the LFE+Main, or double bass which is what it is called in my unit, is a way to get the bass sent to the mains to also be sent to the LFE in order to double, or boost, your main low frequencies since subs are better at that than most mains. Since you are joining the ranks of the active EQ crazies, there is a better option. Get a second active crossover. Send the LFE signal to input one of the second crossover. Send the R and L main frequencies also to the second crossover at inputs 2 and 3. Then, send the MIXED LF output to the subs. With the crossover, you can limit the main signal output to just LF. You will now have the LFE and the LF of the mains going to your subs. All, outside of the AVR. Much easier to do that way. Since you are dealing only with LF, you may be able to get away with just an inexpensive Behringer DCX2496. The beauty of that setup is that you will have total control of your LF main AND LFE signal going to your subs. I have done the above and it works just fine. I hope I made sense. I may be able to help with a DCX2496 at bargain basement prices. Unless you want to get into something more pricey like the Ashly Proea, of which I have a couple as well.

I originally thought of putting some sort of rubber or soft material between the drivers purely to prevent damage to the wires which connect to the diaphragm. I cut them out of some mass loaded vinyl I used for my poly project. However, they are not needed for that purpose. Turns out the bottom of the driver surface is slightly concave and the wires are never under pressure from whatever surface is below the driver. So, I decided to keep it simple and leave out the 'insulator'. I don't think there is any electrical or mechanical issue requiring true isolation....but I certainly could be wrong. I am more concerned on how to seal the area where the wood 45 degree bevel meets the areas of the driver where they are indented. I think I have a good solution for that and will mention the result when I put them together.

Not so much patient, just the time it has taken to process this small project. I'm as excited as you to see how, and if, it works well enough to replace some of my gear. 😱

I'm currently away at work, but by middle of this month I should have some initial impressions to share, at least on what I built.

PM inbound.

Very interesting. What is the highest frequency you can use with the OB subs?

At this point I just want to forge ahead setting up what I have and taking the time to see how it sounds once completely set up. I experimented for some time and at this point just wish to get moving so I can later decide which system to use. I'm sure as time goes on and we get more time and experience, many more experiments will present themselves. That is why I created a bottom plate that holds threaded rods. The rods and bottom plate will keep the drivers and wings in alignment no matter where you move the whole thing. Just happened that the drivers come with the holes for shorter rods. My plan is to also attach a terminal strip to the back so as to keep the connections secure as I move the unit around. I will want to experiment with the unit moved forward so there is no "bottom" to the front edge of the driver. Also, move it back so the wings are flush with the front of my LF cabinet. The Xilica will easily allow me to set up timing for both setups and allow for very quick settings swap during listening. I have a feeling that type of evaluation is more suited to 'listening' than 'measuring'. Should this project prove to be a success, then I can take my time and experiment with longer wings. I would like to work on something like that once I have a good feel for the sound of the stacked drivers.

I started out with smaller prototypes which also worked. After talking to @Chris A, he recommended wider for better response IIRC. That width is simply due to the easily available stock. Feel free to try wider ones and report back.

I know. Haven't figured out a way to do that with purely OB.

I looked at the specs on that driver. Very much a good driver for OB operation I think. What, if any, would be the down side to using two of these per channel? I have built many OB structures but only used Eminence Kappalite 3015LF drivers, which are not ideally suited for OB use. I really like the OB sound and would love to be able to build something that could go from near 20hz up to 1.2kHz. That would allow me to use stay with a two way system.

On second thought. Disregard my OB comments. I really want to try and keep this thread oriented toward the possible ESS kit for Heritage.