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post #91 of 493 Old 01-30-2014, 06:19 PM - Thread Starter
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You mean that contraption with an unterminated horn jutting out of the pole piece and dangling in front of the woofer? Perhaps they have their uses as stage monitors or whatever, but for reproduction of music in the home...I'll leave those to other people.

What makes that built in horn so bad?
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post #92 of 493 Old 01-30-2014, 06:28 PM
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Originally Posted by DS-21 View Post

You mean that contraption with an unterminated horn jutting out of the pole piece and dangling in front of the woofer? Perhaps they have their uses as stage monitors or whatever, but for reproduction of music in the home...I'll leave those to other people.

What makes that built in horn so bad?

I'm not an expert by any means, but isn't a small horn like that not mounted to a baffle or anything going to create all kinds of diffraction off the edge of the mouth? Not to mention that it's blocking 75% of the woofer... :shrug:
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post #93 of 493 Old 01-30-2014, 06:40 PM
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Exactly the stuff the SEOS was all about correcting...
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post #94 of 493 Old 01-30-2014, 07:08 PM
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Okay, so now some of you guys are saying that the Beyma 8CX300Nd drivers wouldn't be all the great to use for surrounds?



Do you think it would be better to use the B&C 8CXN51's

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post #95 of 493 Old 01-30-2014, 07:17 PM
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Okay, so now some of you guys are saying that the Beyma 8CX300Nd drivers wouldn't be all the great to use for surrounds?



Do you think it would be better to use the B&C 8CXN51's

No, not better. For surround systems they would both make great speakers. I have two of the Beymas on the way for my side speakers.
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post #96 of 493 Old 01-30-2014, 07:29 PM
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It wouldn't bother me to use either of them, my biggest concern with any speaker that I end up using is getting the most of them by having the best crossovers to use with them. So either way I think I'd need someone to design some custom crossovers for me. At least with the Beyma mtg90 is going to design a custom crossover for his Beyma's that I could copy.

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post #97 of 493 Old 01-30-2014, 07:58 PM
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Erich ordered the 8fcx51 so I'm hoping we see a custom x-over for it as well.
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post #98 of 493 Old 01-30-2014, 08:08 PM
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It seems the JTR Slant 8s have been highly regarded perhaps the BMS driver might be a reasonable option.
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post #99 of 493 Old 01-31-2014, 04:17 PM - Thread Starter
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I received some packages today with some custom made stuff inside. I'll try to get photos up tomorrow.

One thing I did have time to check was a custom adapter that lets us mount a bolt on compression driver to a screw on coaxial. They make adapters already, but the threaded part is too short and won't screw all the way down inside a coaxial to completely seat itself. Plus if you bolt on your compression driver, then screw in the adapter, the bolt heads will hit the woofer magnet and then it can't seat all the way in either. Easy fix though. Get one made from aluminum with a longer threaded post, then grind down the threaded post until it's just the right length to seat itself and still have clearance for the bolts. I tried them out and they work fine. So we could use a DNA-360 on the back of a Eminence 10" or 12" model now.

But, I might have stumbled across something interesting if I can make it work out. It's a mounting plate that gets screwed on the front of a compression driver during manufacturing. Like the plastic part on this B&C DE10:



There's a tapered pointy phase plug hiding inside of that chunk of plastic. Obviously the phase plug isn't long enough to get inside the horn's throat. Well I found a mounting plate that has a much longer phase plug, and it happens to be for a screw on compression driver. I'll need to get photos. When it's screwed into the Eminence coaxial, the phase plug is so long that it actually protrudes up through that small aluminum "horn" inside the woofer. Looks like I need to chop open an Eminence coaxial to show you guys what I'm talking about. I wonder if a phase plug that long would have any advantage? I think it might.

I also have some interesting coaxials. Yes, some are custom made. One looks neat, but probably won't work very well. I think you guys might like some of these. biggrin.gif
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post #100 of 493 Old 01-31-2014, 04:25 PM
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Originally Posted by Erich H View Post

I received some packages today with some custom made stuff inside. I'll try to get photos up tomorrow.

One thing I did have time to check was a custom adapter that lets us mount a bolt on compression driver to a screw on coaxial. They make adapters already, but the threaded part is too short and won't screw all the way down inside a coaxial to completely seat itself. Plus if you bolt on your compression driver, then screw in the adapter, the bolt heads will hit the woofer magnet and then it can't seat all the way in either. Easy fix though. Get one made from aluminum with a longer threaded post, then grind down the threaded post until it's just the right length to seat itself and still have clearance for the bolts. I tried them out and they work fine. So we could use a DNA-360 on the back of a Eminence 10" or 12" model now.

But, I might have stumbled across something interesting if I can make it work out. It's a mounting plate that gets screwed on the front of a compression driver during manufacturing. Like the plastic part on this B&C DE10:



There's a tapered pointy phase plug hiding inside of that chunk of plastic. Obviously the phase plug isn't long enough to get inside the horn's throat. Well I found a mounting plate that has a much longer phase plug, and it happens to be for a screw on compression driver. I'll need to get photos. When it's screwed into the Eminence coaxial, the phase plug is so long that it actually protrudes up through that small aluminum "horn" inside the woofer. Looks like I need to chop open an Eminence coaxial to show you guys what I'm talking about. I wonder if a phase plug that long would have any advantage? I think it might.

I also have some interesting coaxials. Yes, some are custom made. One looks neat, but probably won't work very well. I think you guys might like some of these. biggrin.gif
Would it fit on the 8 inch?

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post #101 of 493 Old 01-31-2014, 04:26 PM
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Quote:
Originally Posted by Erich H View Post

I also have some interesting coaxials. Yes, some are custom made. One looks neat, but probably won't work very well. I think you guys might like some of these. biggrin.gif

coax tease! tongue.gif
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post #102 of 493 Old 01-31-2014, 04:35 PM
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Cool biggrin.gif
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post #103 of 493 Old 01-31-2014, 04:41 PM
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I love it. Keep pushing ahead
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post #104 of 493 Old 01-31-2014, 05:57 PM - Thread Starter
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I'm heading back down to the 'audio work shop' to get some photos.

I came home to look for a sample compression driver that I got 2 years ago that would work with that long phase plug set up I mentioned above.....but I think I threw the 2 samples away thinking they would never get used. They weren't that bad either. Maybe I have them stored somewhere else though.
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post #105 of 493 Old 01-31-2014, 07:35 PM - Thread Starter
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Here's the adapter with the longer threads that would screw all the way into the back of the Eminence and still have clearance to keep the bolt heads from hitting the magnet:




This photo shows the adapter next to the compression driver back plate with the big phase plug. It also shows how beefy the aluminum adapter is compared to the plastic one in the back ground. Beefy enough......to hold the 10lb BA-750.




This shows how far inside the phase plug would actually go if the proper compression driver could be found. It would actually go up into the aluminum horn.




I need to find the right compression driver for this to work on so I can try out the new idea. biggrin.gif
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post #106 of 493 Old 01-31-2014, 07:49 PM - Thread Starter
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Let's start the neat stuff. biggrin.gif

6" coaxial with built in compression driver (back plate has been removed to show the guts). Aluminum phase plug and copper shorting ring to make it a bit more 'high end'. I'll try to get some different diaphragm materials, shapes, and sizes to see if they can be tweaked a bit. But the terminals on these diaphragms are farther apart than any sample stuff I had from last year while working on some of the other stuff.




8" coaxial with built in compression driver. I like this model a lot. I put the pen up next to it for scale. But the pen is out front and makes the driver look smaller. rolleyes.gif


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post #107 of 493 Old 01-31-2014, 08:03 PM
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Now this one definitely has my interest!

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post #108 of 493 Old 01-31-2014, 10:16 PM
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I really like those 6 and 8". Particularly the 8, cause I like 8" drivers. Very nice.
BeeTL likes this.
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post #109 of 493 Old 01-31-2014, 11:37 PM
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We need measurements....those look very promising for many applications.

JSS
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post #110 of 493 Old 02-01-2014, 02:57 AM
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SM100 like for me. What kind of price are these examples?
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post #111 of 493 Old 02-01-2014, 06:05 AM - Thread Starter
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I don't know costs yet because these are just samples which are normally priced very high. Plus shipping on them is really expensive, so there's no way to calculate things until later. Right now it's just experimenting. I asked for one of the 8" and one of the 6" models to be made with a rubber surround to see if they can get some lower extension. They did that on one of the 6" models, but not the 8". Bummer. But this was a bit of a rush order, so it is what it is.

I've got 2 other samples that I need to post photos of........the funky ones.
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post #112 of 493 Old 02-01-2014, 06:09 AM - Thread Starter
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I should note that I had two SEOS-24's that I bought on the last pallet that had a 1.5" throat but the mounting plate was too small for some JBL drivers.

Soooooo, last week I chopped the back side off and will try to make an adapter to put an 8" coaxial on this bad boy! I need to get some photos of my hack job because I have questions on how you guys think the woofer should be mounted.
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post #113 of 493 Old 02-01-2014, 06:58 AM
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Quote:
Originally Posted by Erich H View Post

I received some packages today with some custom made stuff inside. I'll try to get photos up tomorrow.

One thing I did have time to check was a custom adapter that lets us mount a bolt on compression driver to a screw on coaxial. They make adapters already, but the threaded part is too short and won't screw all the way down inside a coaxial to completely seat itself. Plus if you bolt on your compression driver, then screw in the adapter, the bolt heads will hit the woofer magnet and then it can't seat all the way in either. Easy fix though. Get one made from aluminum with a longer threaded post, then grind down the threaded post until it's just the right length to seat itself and still have clearance for the bolts. I tried them out and they work fine. So we could use a DNA-360 on the back of a Eminence 10" or 12" model now.

But, I might have stumbled across something interesting if I can make it work out. It's a mounting plate that gets screwed on the front of a compression driver during manufacturing. Like the plastic part on this B&C DE10:



There's a tapered pointy phase plug hiding inside of that chunk of plastic. Obviously the phase plug isn't long enough to get inside the horn's throat. Well I found a mounting plate that has a much longer phase plug, and it happens to be for a screw on compression driver. I'll need to get photos. When it's screwed into the Eminence coaxial, the phase plug is so long that it actually protrudes up through that small aluminum "horn" inside the woofer. Looks like I need to chop open an Eminence coaxial to show you guys what I'm talking about. I wonder if a phase plug that long would have any advantage? I think it might.

I also have some interesting coaxials. Yes, some are custom made. One looks neat, but probably won't work very well. I think you guys might like some of these. biggrin.gif
Eric, a volt v-10 with a DNA-360 compression driver would make a greater center channel between a tempest or sentinel for those with no AT screens!!
Make it so even if the price goes up $200 or more...
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post #114 of 493 Old 02-01-2014, 07:18 AM
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A couple thoughts.

I wouldn't worry about a rubber surround and how much low end output a coax can make. It seems fairly unanimous that a coax should not modulate. So it should be high passed.

Why did you wreck a SEOS 24? What are you planning there? :O I'm not sure what will happen.
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post #115 of 493 Old 02-01-2014, 07:30 AM - Thread Starter
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Why did you wreck a SEOS 24? What are you planning there? :O I'm not sure what will happen.

Your last sentence is why I did it. biggrin.gif
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post #116 of 493 Old 02-01-2014, 07:31 AM
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I am very intrigued by the coax samples, especially the 8". I wonder what the horns out the front to cone looks like, that is the $64,000 question with coaxs.

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post #117 of 493 Old 02-01-2014, 07:37 AM - Thread Starter
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Those 2 small models don't have the horns coming out really far. They look like the typical 8" B&C or Eminence set up.

I do have 2 other larger models with the bigger horn sticking out the front. They're the funky looking coaxials I mentioned before. The horns they have probably aren't going to work, but they only had a certain shape they could use at the time. But I did get them made with some neat frames. smile.gif
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post #118 of 493 Old 02-01-2014, 07:58 AM
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Maybe horns wasn't the right word. I mean from the phaseplug to the cone there is a throat. What does that look like on those? The idea of mounting the compression drivers diaphragm in the back magnet is very intriguing as it is more concentrically located mean a much shorter throat and more "time aligned" positionally. That makes them interesting, but I am very curious to know what the throat looks like.

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post #119 of 493 Old 02-01-2014, 08:55 AM
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Quote:
Originally Posted by Erich H View Post

I received some packages today with some custom made stuff inside. I'll try to get photos up tomorrow.

One thing I did have time to check was a custom adapter that lets us mount a bolt on compression driver to a screw on coaxial. They make adapters already, but the threaded part is too short and won't screw all the way down inside a coaxial to completely seat itself. Plus if you bolt on your compression driver, then screw in the adapter, the bolt heads will hit the woofer magnet and then it can't seat all the way in either. Easy fix though. Get one made from aluminum with a longer threaded post, then grind down the threaded post until it's just the right length to seat itself and still have clearance for the bolts. I tried them out and they work fine. So we could use a DNA-360 on the back of a Eminence 10" or 12" model now.

But, I might have stumbled across something interesting if I can make it work out. It's a mounting plate that gets screwed on the front of a compression driver during manufacturing. Like the plastic part on this B&C DE10:



There's a tapered pointy phase plug hiding inside of that chunk of plastic. Obviously the phase plug isn't long enough to get inside the horn's throat. Well I found a mounting plate that has a much longer phase plug, and it happens to be for a screw on compression driver. I'll need to get photos. When it's screwed into the Eminence coaxial, the phase plug is so long that it actually protrudes up through that small aluminum "horn" inside the woofer. Looks like I need to chop open an Eminence coaxial to show you guys what I'm talking about. I wonder if a phase plug that long would have any advantage? I think it might.

I also have some interesting coaxials. Yes, some are custom made. One looks neat, but probably won't work very well. I think you guys might like some of these. biggrin.gif

With these adapters would the dna360 fit on the eminence 8 inch coax?

3 - JTR 228's LCR (game room)
2 - DIY Sound Group V-8 Coaxials (game room)
4 - PSA Triax's (game room)
2 - SVS SB13+'s (living room)
1 - SVS SB12-NSD (bedroom)
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post #120 of 493 Old 02-01-2014, 09:33 AM - Thread Starter
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Yes, the new adapters will let us mount the 360 or the 205 to the 8" coaxial. But I don't think there is much to gain over the current V-8 design. The CD used in the V-8 really is a good driver. Every person that's used it while designing has been pleased. And I'm pretty sure the woofer would give out before the CD would.
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