Fine fine fine...Mag v4 T/S's. ;)

[Electrodynamic]

Xmax was "reduced" over the Brahma because the Mag is 2" shallower than the Brahma.


There's a thread in the technical section of this forum that answers your question.

[splxtreme]

Doesn't the low end come from excursion, or at least some of it? If I remember right, doesn't a sub require about 4 times the excursion when you drop an octave, to keep the FR flat? The ED 13av2 that I did have, the linear xmax on the driver was 28mm, and the fs was 24hz. The xsus was around 54 one way, and I thought, even though it isn't linear, it is still usable. Will the lowend be close? I understand I will not get the output like this driver, but the lowend would play flat below 20hz easy and with great output at that. This was in a .9 cubic foot enclosure, with about 1200rms. So close in recommended enclosure size. I guess in my mind, 22mm isn't enough. But, I could be wrong, and I hope that I am, because the Mag sounds like an incredible driver. I'm looking for something with some excellent sq, but I do like to turn it up when a good song comes on

[Electrodynamic]

Unless you had around 2000+ watts on your eD, you weren't getting any more travel than ~39mm total in that 0.9 ft^3 enclosure. The previous thread I posted up here explains why you don't need 45mm of one way travel for a small sealed subwoofer. Subwoofer cone excursion is very dependent on the size and type of enclosure you put the woofer in.

When you drop an octave, the driver needs to move twice as far in order to keep SPL constant. This is, of course, power dependent also. The new Mag is able to move over 40mm total, with over 32mm of that being extremely linear. Within 27mm of cone travel there is less than a 5% BL variance, and with 22mm of cone travel there is less than 1% of BL variance. The eD doesn't manage that kind of linearity...at all.

And as with all non-linear BL drivers (like the eD), when BL changes, your parameters shift and distortion creeps up. Within 27mm of total cone travel the new Mag manages to keep BL more constant than the 13Av2 does. And that's where it counts, because you're not going to be moving that far under normal circumstances anyway.

In the recommended enclosure, the new Mag will play very flat down to 20 Hz without any problem at all. Playing low isn't always about high power. It just takes high power to play low if your subwoofer can't do it to begin with and you have to shove more power to it in order to regain where the subwoofer left off. Which brings me to my next point - that is what the new Mag is all about: regaining efficiency! Why lob around a 55+ lb monster that just plays low, loud, and nothing more if it sounds like poo and requires an electrical-system re-vamp just to do so?

[splxtreme]

Originally Posted by Electrodynamic

Unless you had around 2000+ watts on your eD, you weren't getting any more travel than ~39mm total in that 0.9 ft^3 enclosure. The previous thread I posted up here explains why you don't need 45mm of one way travel for a small sealed subwoofer. Subwoofer cone excursion is very dependent on the size and type of enclosure you put the woofer in.

When you drop an octave, the driver needs to move twice as far in order to keep SPL constant. This is, of course, power dependent also. The new Mag is able to move over 40mm total, with over 32mm of that being extremely linear. Within 27mm of cone travel there is less than a 5% BL variance, and with 22mm of cone travel there is less than 1% of BL variance. The eD doesn't manage that kind of linearity...at all.

And as with all non-linear BL drivers (like the eD), when BL changes, your parameters shift and distortion creeps up. Within 27mm of total cone travel the new Mag manages to keep BL more constant than the 13Av2 does. And that's where it counts, because you're not going to be moving that far under normal circumstances anyway.

In the recommended enclosure, the new Mag will play very flat down to 20 Hz without any problem at all. Playing low isn't always about high power. It just takes high power to play low if your subwoofer can't do it to begin with and you have to shove more power to it in order to regain where the subwoofer left off. Which brings me to my next point - that is what the new Mag is all about: regaining efficiency! Why lob around a 55+ lb monster that just plays low, loud, and nothing more if it sounds like poo and requires an electrical-system re-vamp just to do so?

You obviously know more than I do, but visually, in the enclosure I had it in, and maybe it is just the way the driver was designed, but the sub was moving way more than 39mm. 1 inch is about 25mm, and the driver was easily around 3in at full volume, even 2in is 50mm. Was it non-linear, probably, but it was able to do it. i think software gives you a general idea, but isn't always right. Maybe there is something else about the driver, that allowed it to be more efficient in the low end, I'm not sure. But, when I get my truck back I will order a Mag and see for myself what it will sound like.

Also, I don't want to start any battles here. I'm just trying to make a point that the driver was able to move quite a bit in that enclosure, and this is with bass music. I can understand the driver not moving much at like 50hz, but getting close to the fs it should move, much more. I haven't plugged the t/s of the av2 in winisd yet, so I'll see what it says.

[splxtreme]

Now, here is what I have from Winisd. Let me know what you think about the excursion plot? Way more excursion below 40hz.

Capture2.jpg

[Electrodynamic]

Yep, way more cone excursion. I had not modeled the 13A at the time (or, for that matter, even now). The W7 is close to the Mag in terms of cone excursion so I didn't look any further at other drivers (and for what it's worth, the Klippel data wasn't out on the eD at the time I did the small model).

[splxtreme]

Plus, I just wanted to make sure you were aware that there is a driver that is capable of such excursion in such a small box. I was trying to get it to play something above 60hz, but because of inductance, it was a no go. I will still try the Mag and see how it sounds. Hopefully, for my picky taste, it will work great.

I like the fact that it is so shallow. I may or may not need 2 to equal the output of the av2, but we will see. I'm sure it will sound better, because the group delay was apparent in the av2. Also, it took 600 more watts to get up to the av2's excursion, but because of the suspension, it looks like you are limited to a very max of 1400 at 20hz, in the 1ft^3 box. Anyways, getting too into this topic. I look forward to testing the Mag out.

[sundownz]

If you are really after a high level of output - you'll want two of the Mags, IMO.

One blends great with the front stage - but if you have a touch of bass-head in you I would suggest two

[Tirefryr]

Who's idea was it to use Xmax as a marketing tool? I want to smack them.

I wonder how all those wonderful drivers in the late 80s and 90s had any low end with the piddly 5mm Xmax. . .

[bose301s]

Originally Posted by Tirefryr

Who's idea was it to use Xmax as a marketing tool? I want to smack them.

I wonder how all those wonderful drivers in the late 80s and 90s had any low end with the piddly 5mm Xmax. . .

Because Xmax looks cool on a spec sheet and it is very visible in videos and demos.