Mag review

[Electrodynamic 2]

I have been listening and listening and listening to the new Mag for a few weeks now in our '94 Civic hatchback with the woofer in 1.3 cubes sealed off two channels of a SAZ-100.4. I wrote the following first bit after I spent 4 or so hours with the driver. The more I keep listening the more I feel like I should update the review. So what I'm going to do is keep this thread open and keep adding to the original text. What you will see is not reply's, but the text will grow as time goes on. I'm not going to lie though, a lot of the material I use for testing subs isn't in a lot of people's CD libraries. Having said that, I will post the album title and artist of the material I am using so you can either download the song/album (legally of course...you don't want the RIAA on you (note the sarcasm)) or buy the CD.

I got the driver hooked up in 1.2 cubes in the Civic tonight!!! It

[bose301s 1]

You really need to listen to some Pink Floyd, my suggestion would be Comfortably Numb, Another Brick in the Wall, Mother, well hell, pretty much all of Pink Floyd's stuff. It has amazing SQ and very tight and controlled bass that hits pretty good. Whenever I demo my car or home stereo those are the songs I use.

[Electrodynamic 2]

I just updated the post with two songs. I'll see if I can get my hands on som Pink Floyd. I've heard Pink Floyd on other peoples systems (mainly home), but never in a car.

[bose301s 1]

I just updated the post with two songs. I'll see if I can get my hands on som Pink Floyd. I've heard Pink Floyd on other peoples systems (mainly home), but never in a car.

Yes, you added a Tool album!!! I love Tool!

Also Nick, YGPM.

Edited February 21, 2008 by bose301s

[Penguin4x4 1,761]

Ouch, that crossover is way too high

[bose301s 1]

Ouch, that crossover is way too high

No, it isn't. The new Mag can play up in those ranges without a problem.

[Electrodynamic 2]

I just updated again, the x-over is at ~100 Hz now. I started the test (before the first writeup) at 50 Hz and kept bumping it up and up and up so I just said screw it and lowered it back down to 150 Hz because it still didn't muddy anything up. But like I said, the x-over is at ~100 Hz now.

[1sashenka 0]

I just updated again, the x-over is at ~100 Hz now. I started the test (before the first writeup) at 50 Hz and kept bumping it up and up and up so I just said screw it and lowered it back down to 150 Hz because it still didn't muddy anything up. But like I said, the x-over is at ~100 Hz now.

It sounds excellent, that Mag is able to go that high. However, I always felt if I crossed the sub too high, I ran into sound localization issues - meaning I could hear the bass coming from the rear, which screwed up my soundstage. I don't like to be able to tell where the music is coming from. These days I never cross my sub over 80hz. I think it is even lower right now at around 70hz or so, and my subsonic is rather high at around 30hz. But man, do I get nice bass in those frequencies with my Arc Audio KS1000.1.

[Electrodynamic 2]

It sounds excellent, that Mag is able to go that high. However, I always felt if I crossed the sub too high, I ran into sound localization issues - meaning I could hear the bass coming from the rear, which screwed up my soundstage. I don't like to be able to tell where the music is coming from. These days I never cross my sub over 80hz. I think it is even lower right now at around 70hz or so, and my subsonic is rather high at around 30hz. But man, do I get nice bass in those frequencies with my Arc Audio KS1000.1.

The Mag can actually play clean up to 900 Hz before it starts breaking up. If you ignore the 3 dB dip it can play out beyond 1.2kHz.

You're right on the x-over settings though. I usually run around with mine at 80 Hz for fun and 65 Hz for more discerning listening. Higher points do localize the driver more because mids start coming through.

[omarmipi 0]

You really need to listen to some Pink Floyd, my suggestion would be Comfortably Numb, Another Brick in the Wall, Mother, well hell, pretty much all of Pink Floyd's stuff. It has amazing SQ and very tight and controlled bass that hits pretty good. Whenever I demo my car or home stereo those are the songs I use.

Don't forget "Welcome to the Machine"

It's awesome that the new Mag can play that high. Are you going to post distortion plots, frequency response, t/s parameters?

I just might go back to a simple 2-way (no 8" midbass) since my PPI PSC-221 will help with the lower frequency localization. How high is sensitivity? I am interested in using some pro audio midrange drivers (18sound) and the Peerless HDS, which are both around 92 dB @ 8ohms.

[Electrodynamic 2]

Sensitivity is rated lower than the previous Mag. The result is more output while using less power from 100 Hz on down. I'm going to post Fs, Qts, Le and Re graphs over excursion / power delivered. I'll also post up the same graphs with the previous Mag, which will be VERY interesting to a lot of you guys.

[Penguin4x4 1,761]

Ouch, that crossover is way too high

No, it isn't. The new Mag can play up in those ranges without a problem.

Most every subwoofer I know of can, doesn't mean they should

Edited February 22, 2008 by Penguin4x4

[Electrodynamic 2]

Most every subwoofer I know of can, doesn't mean they should

They might be able to play that high, but not without encountering breakup first.

Anyway, I was experimenting with such a high x-over to see how the driver sounded. It sounded so good with it being that high I just left it for a while. The x-over is now at 100 Hz, and will probably go down to 80'ish this weekend.

[1sashenka 0]

Sensitivity is rated lower than the previous Mag. The result is more output while using less power from 100 Hz on down. I'm going to post Fs, Qts, Le and Re graphs over excursion / power delivered. I'll also post up the same graphs with the previous Mag, which will be VERY interesting to a lot of you guys.

Please forgive me, but I don't understand how a driver could sound louder being less sensitive. I always thought if you have 500 watts, the 92db driver would get louder than say 89db driver. Can you please explain? Cause right now I am struggling with a 84db DIYMA sub, and it is the cleanest sub I heard, but output is so low, that it's unreasonable and very disappointing. It is in tiny 0.7 cubes, I know, but I am giving it 850 watts, and it still whispers to itself back there.

I can't help to think, that the sensitivity was lowered, because the sub was obviously made less rugged, and so it could still take some power without getting itself into distortion/break up and such problems, and also because the sub is designed to be in smaller enclosure.

Edited February 22, 2008 by 1sashenka

[sundownz 197]

Sensitivity is rated lower than the previous Mag. The result is more output while using less power from 100 Hz on down. I'm going to post Fs, Qts, Le and Re graphs over excursion / power delivered. I'll also post up the same graphs with the previous Mag, which will be VERY interesting to a lot of you guys.

Please forgive me, but I don't understand how a driver could sound louder being less sensitive. I always thought if you have 500 watts, the 92db driver would get louder than say 89db driver. Can you please explain? Cause right now I am struggling with a 84db DIYMA sub, and it is the cleanest sub I heard, but output is so low, that it's unreasonable and very disappointing. It is in tiny 0.7 cubes, I know, but I am giving it 850 watts, and it still whispers to itself back there.

I can't help to think, that the sensitivity was lowered, because the sub was obviously made less rugged, and so it could still take some power without getting itself into distortion/break up and such problems, and also because the sub is designed to be in smaller enclosure.

Generally a sub with a lower "sensitivity" plays lower than one with a higher sensitivity (at a given size). Comparing output at a frequency above the normal bandwidth of the subwoofer, say, 200 Hz or so the higher sensitivity sub will be louder. But, as you go down lower the reasons for the lowered sensitivity -- usually from higher mass or higher Qts on woofers -- will cause the sub to produce more low-end, which is the whole reason to have a SUB woofer. PA Drivers tend to have a low Qts and very low mass, hence high sensitivity ratings, but they also tend to have almost no SUB bass output compared to a true subwoofer driver. I'm simplifying it a bit, of course, but thats the basic idea you are looking at.

Also, with the Mag it has less BL loss vs. excursion than the older Mag, so it's not losing BL as it begins to move and is thus not becoming less efficient vs. excursion. You can't look at static parameters to determine this, but it is the nature of the dynamic properties of XBL^2 to be more efficient over excursion than a non-flat BL topology.

[Electrodynamic 2]

Generally a sub with a lower "sensitivity" plays lower than one with a higher sensitivity (at a given size). Comparing output at a frequency above the normal bandwidth of the subwoofer, say, 200 Hz or so the higher sensitivity sub will be louder. But, as you go down lower the reasons for the lowered sensitivity -- usually from higher mass or higher Qts on woofers -- will cause the sub to produce more low-end, which is the whole reason to have a SUB woofer. PA Drivers tend to have a low Qts and very low mass, hence high sensitivity ratings, but they also tend to have almost no SUB bass output compared to a true subwoofer driver. I'm simplifying it a bit, of course, but thats the basic idea you are looking at.

Also, with the Mag it has less BL loss vs. excursion than the older Mag, so it's not losing BL as it begins to move and is thus not becoming less efficient vs. excursion. You can't look at static parameters to determine this, but it is the nature of the dynamic properties of XBL^2 to be more efficient over excursion than a non-flat BL topology.

^ What he said.

Ok, instead of having you (or anyone) model something up to help explain what I was about to explain I'll model it up real quick and post a graph. I'm going to use a PA 12" driver in 1 cube sealed and the new Mag 12 in 1 cube sealed to show you what Jake and I are talking about. Like Jake said, above 200 Hz, sensitivity means a lot if you're talking about a midrange. When you're after output below 100 Hz, high sensitivity is a bad thing. Like Jake said, high sensitivity drivers have moving mass's that are too low, Xmax's too low, and usually Qts's that are too low to provide any real output in the subwoofer region.

Concerning the driver you are talking about (the DIY), take a look at the Great 12 Challenge results. The driver didn't fair well at all. It's a neat looking driver, but output wise it provided very little and proved to be a brittle driver (mainly the cone). The light moving mass approach is a good one...if, and only if, you have the other parameters in check so that you still have good output. Like Jake said above, and I've said before, if you have that kind of mass you need a high Qts in order to regain output down low. Low Q, high BL, low moving mass drivers are not good subwoofers.

Anyway, here is a graph of an Eminence 12" high-efficiency woofer (97 dB) against the new Mag 12" (86 dB). Both are in 1 cube sealed.

The green horizontal line is 0 dB, the red trace is the Mag and the blue trace is the Eminence.

The Mag's F3 is 40 Hz compared to the Eminence's F3 of 79 Hz.

The thing to keep in mind is that there is a clear difference between efficiency and output. Two completely different things. What the new Mag was designed for was output in 1 cube sealed or 1.5 cubes vented. It wasn't designed to hit a great 1W/1M number because if it was designed for that, it wouldn't produce any real sub bass.

[danssoslow 0]

If you could take a request, could you take a listen at D'Angelo's "Brown Sugar"? I haven't heard many car audio systems that didn't sound muddy playing the first 20 seconds of that song.

[Electrodynamic 2]

I'll listen to anything you guys send me. I don't have anything by D'Angelo.