Electrodynamic

11 and 1/16'th

Cool, thanks for the update with the drawing! Pretty impressive if I do say so myself. I wish there was an audio society where I went to college.

http://www.audiojunkies.com/blog/836#continued

XBL^2 actually makes almost any driver more efficient. Not only are you cutting your moving mass down a lot, you're lowering inductance a lot, and keeping (if not increasing) linear throw. Although you CAN make an XBL^2 driver inefficient by coil type, suspension compliance, added weight, an inefficient motor, etc. Just like you can say an overhung driver is inefficient - take a look at a PA overhung driver at 110 dB with 1 watt compared to an Eclipse center channel at 76 dB with 1 watt. Basically, you can take any topology and make it inefficient. But no, XBL^2 does not make a driver less efficient.

Not yet. I will divulge pricing when pricing is finalized (hopefully shortly after the new year - January'ish).

Nope, no neo for many reasons. This will be a 'traditional' ferrite magnet sub (I emphasized traditional because the Mag gets the good/expensive ferrite magnets and not the cheap crap that most people use).

Copper on the pole. The pole will be anodized copper and then diamond cnc machined down to the apropriate diameter, which will do two things: Help with heat disipation; Act as a shorting ring further lowering inductance.

Basically everything is going to be brand new on the new Mag. The only thing that is remaining the same is the voice coil former diameter, but that's it. The voice coil windings we are going to use on the new Mag are copper, not aluminum, to get the moving mass where we want it. As some of you know, one of the features of XBL^2 is being able to use a much shorter voice coil and still get good/high amounts of linear excursion. This allows inductance to go down (again, raising the bandwidth capability of the speaker) without sacrificing excursion. An aluminum former will still be used (with a little trick that mimics the benefits of titanium). The cone is completely different, but the same as the old Mag. The cone is paper, but the composition is wildly different and beneficial. Our previous cone could hold about 60 lbs of weight on the back of the cone (cone facing down) without deforming. The new cone can hold 140+ pounds without deforming. Now, let me point out that is without a former attached!! That is just the raw cone, nothing more. ...and there is no significant weight difference either. The surround has also been changed to a more linear foam surround. You won't be able to tell that the difference in the new surround to the old surround because it looks and feels just like our previous surround. It does offer better performance though. Lets see... I think that's all for now. Expect to see some updates on audiojunkies.com in the next few days (I sent Lukas some pretty pictures to use).

I'm not sure where that mis-information came from (playing 60 Hz and below) because XBL^2 extends the usable range of a subwoofer, not limits the range of a subwoofer. Our previous Mag's stopped at about 70-80 Hz due to inductance and the new Mag's are going to play up to 300-400 because of the inductance cut of 3x the previous version.

1000 watts is an excess of what it needs to reach full excursion. The new Mag is going to be more efficient than the current Mag. The 1000 watt power handling is just that - power handling. It will need far less than that to produce great output. The new Mag still has the same goals for a driver, except now it's more focused on SQ and less thermal tons of power soak-up (the new one's won't handle 1800 watts all day / 2800 watts for burps like the previous versions). I was originally planning on running an SAZ-3000D on a pair, but that's beyond overkill for what the new Mag's are going to be able to do off of lower amounts of power. I think I might do a SAZ-1500D on a pair just to show off how efficient they are. I'm also going to weigh the enclosure and subs, get everything metered, and then put in the previous Mags (the one's wer're sold out of now) and get it re-metered and re-weighed. Or I might do four 12" BM's in a floor behind the rear seats to show off how shallow they are, which will also show off how much trunk room you can have while still having an arse load of bass. But first I need to sell the 'teggy.

Well Adire has gone under, RE only builds for RE now, and we're not using Fi. There are other build houses who can build a driver using XBL^2, but you are right; it's not common place. I'll post the drawing of the basket this week for you. And after the drawing is posted I'll post the picture of it. Same with the new BM - draing first, pic second.

Neither the Mag's nor the BM's are being built by any of those companies listed. The most important thing to remember about build houses is this: don't worry about it. I've got a drawing and a picture of the basket I'm going to use. I could post that up, but it doesn't do the finished driver any justice.

Well that's good to hear! Instead of 140 dB weighing 120 lbs, wouldn't it be nice to be able to do 140 dB weighing 65 lbs? Not to mention being able to keep your trunk/hatch area. And then there's the BM's. Those shallow suckers are going to be able to be mounted anywhere - up under your rear deck so you have ALL of your trunk room, behind the seat of a regular cab pickup with the seat all the way back, tucked away behind furniture for HT, etc.

No, the current (black basket, shiny motor) BM's is what he's talking about. The BM's you got emailed about haven't been released or even prototyped yet. Trust me Ryan, you're in the loop as deep as it gets. And for those of you who aren't Ryan or are part of our rep list, there are new BM's coming out that are VERY different from what we've previously released pictures of.

Yes, we horde our BM's for top secret military testing. Wait...well, now that I've told you, I'll have to kill you. Where are you located at anyway?

I know this thread is a teaser because we don't have the pictures uploaded yet, but as of last night we finished up our latest HT. The system includes a Denon 7.1 receiver, Denon up-converting DVD player, Panasonic 1080p HD projector, HDMI cabling, 20 Hidden Audio transducers, 124" 16:9 screen, Lutron automated lighting, MX900 remote, 2400 watt amplifier, and four BM 12's ported to 30 Hz in a 12 ft^3 box. The neat thing about using Denon receivers is that the upper models (this customer has a 987 model) have a 7 band EQ per channel, where each channel can be EQ'd independantly or the same EQ setting applied to all channels. The receiver is also super user-friendly and very little setup is required, although you can still go in a tweak the hell out of your system if you want. We watched Top Gun last night after we were done and the bottom end of his system is incredible. Both Marty and I like the way the four BM's perform better than we do the four Mag 15's IB in the ceiling. #1, the BM's are floor-placed, where as the Mag 15's are IB in the ceiling. The bad thing about ceiling IB systems is that since the enclosure is your attic, the drywall moves slightly (not enough for you to see of course) the further you get away from the drivers location so you loose SPL due to cancellation. Having said that, the floor-mounted BM's SLAM! They are incredibly loud even though they're not moving any further than 10mm total. The quatro of BM's operate effortlessly - never moving far enough to warrant any kind of distortion even at ear-splitting levels. There are numerous scenes in Top Gun where the jets are taking off or flying by and the bottom end that the BM's deliver is just intense with impact. The extremely low part of the booms were moving my shirt and jeans when I was sitting on the couch approximately 15' away from the subwoofer enclosure. We're going to go back to the house to demo some of our CD's and DVD's to the home owner pretty soon, so we'll definitely get a better feel for what the system is capable of at that point. The subwoofer enclosure should be covered by that point as well (the enclosure is raw MDF because a decorative cover is being made to conceal the enclosure to where you can't tell that it's even there). Anyway, I'll try to post pics of the screen and the subwoofer tonight or tomorrow!

Nice score!! The BM's are very formidable drivers for sure. When ported those suckers can get nasty!

Very true. No dates from us until after the production run is made and is on its way to us. Some of the parts for the prototype have been cut, so it shouldn't be too much longer until we have a working proto in our hands. And believe me, we're definitely having a Mag party (a meet for those who want to attend). :)

The measurements I supplied are for a vented baffle. For a vented baffle multiply vent width by height and you have square inches.

Thanks for clarifying. Thread is now deleted as per the forum rules.

I'm not sure what this topic has to do with SI products, but if you could enlighten me I would appreciate it. I have it in the rules of this forum to keep this forum for SI topics only, and this isn't SI related as I see it. Not trying to be a butt hole, just curious.

SWEET! (I can see the pics now - don't know why I couldn't before). Looks like you guys are making good progress!! Oh, I swear I'm getting that sticker off to you! It will go out soon.

What helps me the most when wiring that many drivers is using wire thet is black and red. I know it sounds simple, but there is a lot of crap wire out there that has a clear jacket on it with small writing on one side to designate positive. The more easily you can differentiate your wires, the less chance of screwing something up.

70 in^2 is a bit excessive. You can actually stick to 50 in^2 and be just fine. Keep in mind that's a port that measures over 4" tall by 12" wide.

Our newly designed web page is now up!! Many thanks to Cliff, "the abunai", for putting it all together for us. As many of you are thinking, the Mag, BM, and Home Theater pages are going to be updated shortly. But anyway, I love the new web page. Let me know what you think.