Event Horizon: a slim, wall-mounted WMTMW

[ckmoore]

Re: Event Horizon: a slim, wall-mounted WMTMW

I am about to order the parts for the HiVi sealed version myself.

Paul, would you recommend a 3rd one horizontal for the CC, or the MMTMM design you mentioned?

[Paul Carmody]

Re: Event Horizon: a slim, wall-mounted WMTMW

Well, here's where I'm at. I was pretty happy with the crossover--as long as the enclosures were sealed. With a vented alignment on the bass (which is how I'll use them), I wanted more extension, and therefore needed larger cabinets. But I didn't build the larger cabinets yet. And I probably won't get around to it until December sometime.

However, anyone who wants to do the design sealed, send me an email and I'll share the XO and stuff. make sure to specify the HiVi or Dayton ND version.

Also, I was REALLY pleasantly surprised by how nicely the MMTMM turned out for Meniscus (using HiVi B3N). I think that would also work great in a modern HT setup.

So there's progress, but this project has mostly been on-hold. And I'm really swamped with projects, so I don't know if I can complete (that is: finalized, in a vented cabinet, and all the details make sense) this design until the new year.

[dkalsi]

Re: Event Horizon: a slim, wall-mounted WMTMW

Paul,

Any updates? (don't mean to pester - just curious).

[Paul Carmody]

Re: Event Horizon: a slim, wall-mounted WMTMW

This is a type of project I havent seen much of in my limited exposure to DIY. Are there other designs floating around that are specifically designed for on-wall? (not in-wall). And not the super small bose buster types.

You've asked the right question, in my opinion. To my knowledge, there's almost nothing like this in the DIY world. The commercial world is creating speakers like this, and they do look nice. I've studied every commercial offering I could to get ideas in terms of size and proportions, and also just plain "how'd they do it"?

It turns out that this kind of speaker is HARD to do. That is, making a small midwoofer cross low in a 3-way situation, as if it were an 8" or larger, is nearly impossible because of the impedance spike (mentioned earlier in the thread).

Sure, this type of design is a piece of cake to do if it's just a simple 2-way MTM (I could have just made a few adjustments to the OSMTM and called it a day). It turns out that that's almost exactly what the commercial companies all do. YOu either see an MTM in a tall, slender cabinet, or an MTM flanked with several small passive radiators (they look like woofers, doncha know). So, in effect, what you get is a handsome-looking "array" of midwoofers in a slender cabinet, but really only the inside pair are doing the work. You can bet that if us DIYers had access to these kind of small PRs like commercial companies do, that I would have just done a simple 2-way MTM coupled with a bunch of PRs and called it a day a long time ago.

This one by Morduant Short is a perfect example of what I'm talking about.

[ckmoore]

Re: Event Horizon: a slim, wall-mounted WMTMW

This is a type of project I havent seen much of in my limited exposure to DIY. Are there other designs floating around that are specifically designed for on-wall? (not in-wall). And not the super small bose buster types.

[Paul Carmody]

Re: Event Horizon: a slim, wall-mounted WMTMW

Any progress on this Paul?

Also, did you consider MichiganPats suggestion about making them slightly horizontally trapezoidal to get a bit more volume, without increasing baffle size?

If someone wants to design a trapezoidal cabinet for them and build it, that's fine by me. I don't want to do a trapezoidal cabinet design, though, because I think it would appear too difficult to the average hobbyist. I'm really trying to keep it as simple as possible with this project.

Also, how would you compare the sound of these (with Hivi drivers) to the Swopes?
I was all set on the Swopes, but my wife was looking over the shoulder and saw this thread, and said "I didn't know wall mounting like that was an option!" getting excited....

I'm glad it caught your wife's eye. (My wife would be proud, too, since she thinks it's a design "for the wives"). Well, the sound I got out of the HiVis was very pleasing. Sweet-sounding, I suppose. If I were to compare it to the Swopes, I would say it's more like the TM--which I personally thought had some more "character" to their voice than the MTM.

Anyway, the project had to be suspended again because this cabinet I'm using just won't work for the big magnets of the HiVis--and doesn't dig deep enough for the Dayton ND105-4. Soooo.... I'm on to cabinet design #3. I haven't built it yet, but hope to in the next few weeks. And geez, do I hope that cabinet finally works!

[ckmoore]

Re: Event Horizon: a slim, wall-mounted WMTMW

Any progress on this Paul?

Also, did you consider MichiganPats suggestion about making them slightly horizontally trapezoidal to get a bit more volume, without increasing baffle size?


Also, how would you compare the sound of these (with Hivi drivers) to the Swopes?
I was all set on the Swopes, but my wife was looking over the shoulder and saw this thread, and said "I didn't know wall mounting like that was an option!" getting excited....

[brianbunge]

Re: Event Horizon: a slim, wall-mounted WMTMW

Chris Roemer's ntn's use a pair of the ND105-4's in a cabinet roughly .55ft^3, or about 15 liters. His single driver nt's use a .32ft^3 cabinets, or about 7 liters. So far, everyone who's built either of these designs have loved them, including their bass output. I'm building a pair of the ntn's right now but would love these for the living room setup.

[michiganpat]

Re: Event Horizon: a slim, wall-mounted WMTMW

OK. I can do that. Like I said, I already have a larger set of thin cabinets in my garage. They're floorstanders, but I can rig it up to approximate what we're doing. I think the Dayton ND crossover is pretty close to done, but I really need to hear it in the "proper" sized enclosure to make sure.

How long can you wait? ;) I'm half-kidding with that, but I do want to button-up this HiVi version first.

if you wanted to keep the ND105-4's, what about my idea from page 1 of making the cabinet (as viewed from the top) a trapezoid? keep the front baffle the same width, kick the sides out 15 degrees, and you end up with almost 50% more volume....

[brianbunge]

Re: Event Horizon: a slim, wall-mounted WMTMW

Paul,

I'm in no hurry. I currently have a pair of Pete's Prisstina's with matching center but I showed my wife a pic of the Event Horizons and she flipped out and made some comment about getting some floor space back in her living room. ;)

In the meantime I'm working on a pair of Chris' ntn's in tower form for the bedroom.

[Paul Carmody]

Re: Event Horizon: a slim, wall-mounted WMTMW

Well I'm officially bummed! I HATE the looks of the HiVi drivers. And I don't mind the bigger cabinets and would actually prefer 4 of the ND105-4's for even better output. And since I have a screen that's about 52" high I could have gotten away with the taller cabinet mounted next to it...

I agree, I have a projecter screen that the larger ND105 with the larger cabinet would have looked great. Any thoughts on continuing with and modeling the crossover?

OK. I can do that. Like I said, I already have a larger set of thin cabinets in my garage. They're floorstanders, but I can rig it up to approximate what we're doing. I think the Dayton ND crossover is pretty close to done, but I really need to hear it in the "proper" sized enclosure to make sure.

How long can you wait? ;) I'm half-kidding with that, but I do want to button-up this HiVi version first.

[outfitter]

Re: Event Horizon: a slim, wall-mounted WMTMW

Well I'm officially bummed! I HATE the looks of the HiVi drivers. And I don't mind the bigger cabinets and would actually prefer 4 of the ND105-4's for even better output. And since I have a screen that's about 52" high I could have gotten away with the taller cabinet mounted next to it...

I agree, I have a projecter screen that the larger ND105 with the larger cabinet would have looked great. Any thoughts on continuing with and modeling the crossover?

[greywarden]

Re: Event Horizon: a slim, wall-mounted WMTMW

Well I'm officially bummed! I HATE the looks of the HiVi drivers. And I don't mind the bigger cabinets and would actually prefer 4 of the ND105-4's for even better output. And since I have a screen that's about 52" high I could have gotten away with the taller cabinet mounted next to it...

Build your own lol...

[brianbunge]

Re: Event Horizon: a slim, wall-mounted WMTMW

Well I'm officially bummed! I HATE the looks of the HiVi drivers. And I don't mind the bigger cabinets and would actually prefer 4 of the ND105-4's for even better output. And since I have a screen that's about 52" high I could have gotten away with the taller cabinet mounted next to it...

[Pallas]

Re: Event Horizon: a slim, wall-mounted WMTMW

Curious, why vented? It seems to me that this type of speaker is better as a closed box.

That way, you take full advantage of boundary reinforcement down low (rather than giving some away with the 4th order rolloff below tuning) and not worry so much about unit-unit variation in the bass drivers.

Also, boxes with 2d order rolloffs down low are easier to integrate with subwoofers.

The Aura-knockoff Dayton ND's have enough throw to handle the demands of closed boxes, though some gasket material is definitely needed to keep the cheap frames from buzzing. (I used automotive sound deadener sheet on the outside of mine to keep them quieter, as well.)