A little more info on the new Mags

[Penguin4x4 1,761]

Great news, can't wait to see em

[Electrodynamic 2]

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.

[Electrodynamic 2]

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).

[sundownz 197]

w00t

[DevilDriver 28]

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.

It comes from misinterpretation. You take 30mm of linear stroke on a low Fs driver, throw on 1-2kW in a ported enclosure tuned to 30 Hz or lower and you get a low end mammoth....with a top end that sounds limited by comparison. The beauty of the high stroke XBL^2 drivers is that you can cram them in small enclosures and have nice even response for several octaves...the Brahma was a perfect example of this, if integrated well. They got a bit of a bad rap for no real reason.

Like every driver (XBL^2 or not) the enclosure has to suit the driver appropriately...I mean, it's a filter right in the middle of your bandwidth!

I am very interested in the new Mag. Can't wait to see more and would love to hear more about this composite cone.

Very intriguing.

[DevilDriver 28]

Oh, and no one needs to worry about where the drivers are made. There are enough buildhouses that are capable of doing XBL^2 drivers (it's really just a little extra machining) and capable of doing them very well. From what the other XBL^2 guys have told me, Dan has made some very good connections with a number of different buildhouses.

Sorry if I missed it....copper in the rebate, on the pole, or none?

[Electrodynamic 2]

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.

[Megalomaniac 0]

ohsnap a shortening ring

[bose301s 1]

This all sounds very cool. One thing I have forgotten to ask this whole time is will these new drivers be neo motored? It sounds like a possibility considering how small and light you are going with them.

[Electrodynamic 2]

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).

[///M5 2,833]

Hmm, how will the new BM's be IB? At 3.5" I can make them fit in between studs

[bose301s 1]

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).

Ok, good to know. I also want to be a tester for the new Mag 1 final question, would it be better to run 2 Mags off of a pair of SAE-1000Ds strapper for 1800 watts @ 2 ohms or a pair off of a SAZ-1500D @ .5 ohms?

[JoshHd6 0]

price on the new mag?

[Electrodynamic 2]

price on the new mag?

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

[bdawson72 0]

I want new BMs as midbass -- is that so wrong ?

x2

Edited November 28, 2007 by bdawson72

[subwoofery 0]

Not questionning anything here, but I though that the XBL^2 motor topology wasn't really efficient.

I believe I read this on the thread DevilDriver made a few months back.

I'd like to hear an explanation about how SI did this to make the new mag more efficient... Can't wait to see the new MONSTER!!!!!

[Electrodynamic 2]

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.

[Aaron Clinton 2,372]

Every motor type has its strengths and weaknesses. Nick is using XBL^2 and adjusting the sub to make the most of the technology. XBL^2 has a love it or hate it type of sound, but every XBL^2 derivative I have listened to has always been a clean sound, some describe it as dry. Would love to test the next MAG.

[Electrodynamic 2]

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

[Aaron Clinton 2,372]

We already knew you were amazing.

[DevilDriver 28]

Not questionning anything here, but I though that the XBL^2 motor topology wasn't really efficient.

I believe I read this on the thread DevilDriver made a few months back.

I'd like to hear an explanation about how SI did this to make the new mag more efficient... Can't wait to see the new MONSTER!!!!!

This is something I should perhaps clarify. There are many inter-related aspects of efficiency.

Despite the small coil, XBL^2 is more flux efficient than your standard underhung driver (although still not as flux efficient as an overhung driver). This is gained through the rebate in the top plate and/or the rebate in the pole piece. But this also means two things:

1) The steel in the heart of the stroke is further away from coil.

2) There is less steel in the top plate and/or pole piece to carry the flux.

The potential impacts were made much too simple by myself in the original thread, so I will expand on this a bit.

In situation 1, this is only a really big deal if the flux paths are already totally saturated; if they aren't, the impact is minimal as the flux is "steered" elsewhere and jumps the gap anyways. Also, a small sacrifice in efficiency at the heart of the stroke is likely worth it to an engineer to gain efficiency with stroke...where other drivers have a BL that drops drastically as the coil begins to move (thus hurting the average efficiency over stroke), XBL^2 has a flat plateau till the coil starts to leave the gap (with even more travel after that as a fair bit of flux rests in what is called the "fringe field")...that's quite a bit of throw that is substantially more efficient than it's underhung or overhung counterparts....it's the beauty of flat, linear BL.

In situation 2, again, saturation is the key. If the steel is at or approaching saturation (which is tough to do with the large top plates required for XBL^2 or underhung drivers), then yes, taking steel out of the motor is not necessarily a good idea if maximum efficiency is your goal (although it should be noted that a lot of companies do pole vents with the sole purpose of lowering BL by taking steel out of the motor). If the steel is not saturated, then the rebate will have a very small effect.

And, as Nick pointed out, the coil is smaller and weighs less...since mass (Mms in thiele/small parameters) is a component of efficiency, lowering mass will increase efficiency.

So there are a lot of things to consider there. In maximum theoretically possible efficiency, XBL^2 is typically lower than some other topologies (as does nearly every other low BL based distortion topology). However, in practice, it has efficiency that falls on par or exceeds many drivers.

I said this on caraudio.com as well: remember that it is always the implementation of technology that matters, not the technology itself. For reasons such as this, I do need to update that particular thread a bit.

And simply put, this is nothing but a great move on Stereo Integrity's part....don't let anyone else tell you otherwise, either.

[subwoofery 0]

Lucky we have DevilDriver on this forum to share his knowledge

[Aaron Clinton 2,372]

Lucky we have DevilDriver on this forum to share his knowledge

There is a good reason he is on the SSA Tech Team and writes for Audiojunkies.

[jntar 15]

Will there be a preorder this round like last? I know its a little soon to ask at this stage, but Id love to be the first non rep/competitor to get one and test it out like last time.

Id also be willing to buy the proto as soon as you start production to write up a review for you.

[JimJ 11]

Shallow mounting depth does nothing for me, but lowered inductance does

Might be time to put the Shiva in the 2nd system and run stereo subs with the BIB's...