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I'm not getting my hopes up, I asked for the inductance plot a long time ago, still no sign of it. It seems to me they only release the stuff that looks good.
 

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Still doesn't look as impressive as the Polk MMs (which is technically not a "shallow mount"). But at 4 5/8" for a 12 it's definitely a contender.
FYI, I just modelled both the SL10 and MM1040DVC & both the SL12 and MM1240DVC...
You put both 10" in the same enclosure, sealed or vented, and they perform EXACTLY the same - the SL10 being 1 1/2" shallower, it's a better choice
You put both 12" in the same enclosure, sealed or vented, and they perform EXACTLY the same - the SL12 being 1 1/8" shallower, it's a better choice too...

Kelvin
 

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I would think the Alpine sounds the best and gets the loudest. Just look at the Polk for example, it claims 25mm one way xmax and they say they used the Klippel analyzer in the driver production. If so, where is the Klippel report? Alpine publishes it right on their website which imo adds a lot of credibility to their work. Looking at the curves it seems to have 12mm of one way xmax using the most stringent of definitions.
Again comparing both the SL12 and the MM1240DVC, I can't see it having reaching that much Xmax. Looking at both pics, the surround shape looks quite similar and sure doesn't look like a high-roll type of surround like seen on TC Sounds subwoofers...
Mounting diameter for both is the same @ 11" yet the SD of the Polk is much larger @ 520cm2 VS 470cm2 for the SL12

Maybe that's what the extra depth is for I guess :rolleyes: - sure doesn't help with the performance as seen in my previous post...

The only other piece of evidence is a suspension klippel report on the SI, which seems great up to 12mm but the graph is not complete nor do we get the motor plot which is more important.

Based on the available information the Alpine is the best. The rest is all marketing and boasting. Even the Alpine could use a lot more specifications, we still don't have the inductance curve and there isn't even a BL, or MMS specified in the white sheet. I'm not sure how you guys plotted this sub, I couldn't.

As far as box requirements go none of them are true small box subs, and like all speakers it's best to keep a lot of room behind the subwoofer for airflow. These types of low depth installations almost always give up sound quality for ease of install.
Would love to play with the Type R seeing all the rave reviews about them...

Kelvin
 

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FYI, I just modelled both the SL10 and MM1040DVC & both the SL12 and MM1240DVC...
You put both 10" in the same enclosure, sealed or vented, and they perform EXACTLY the same - the SL10 being 1 1/2" shallower, it's a better choice
You put both 12" in the same enclosure, sealed or vented, and they perform EXACTLY the same - the SL12 being 1 1/8" shallower, it's a better choice too...

Kelvin
Did you take into account that the Polk has more excursion and handles more power? They might have the same transfer function, but what about SPL?
 

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But we don't know how much xmax the Polk has. I seriously doubt it has 25mm of linear throw. I doubt it has 12mm of xmax. That's the point, with Alpine you are guaranteed to have 12mm of linear excursion. That's really good considering the low depth.
 

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All we have to go off is the specs at this point. So why not assume all the specs are false?

And at almost 5" mounting depth is it that hard to believe the Polk can't do 12mm?

Besides, my last two post were in reference to the polks vs. the RE SLs.
 

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Did you take into account that the Polk has more excursion and handles more power? They might have the same transfer function, but what about SPL?
EXACTLY THE SAME... Xmax figures, group delay, Amp apparent load, etc...

The SPL curve are within 0.5dB of each other from 10Hz to 60Hz with the SL playing higher better (above 60Hz) probably due to less inductance... but above 60Hz it shouldn't matter coz it's as much as 0.9dB @ 100Hz :p

True that the Polk has more excursion but that doesn't help in SPL figures (thread is "the loudest shallow mount subwoofer")
True that the Polk handles more RMS power but you should know that RE Audio are used to overbuild their subs to handle tons of power.
FYI please click here - I'd like to know if the Polk can handle as much :rolleyes:

Kelvin
 

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And as far as the post in your link goes; isn't that true of any decent sub's RMS rating?
To be honest, I think that it's not necessarily true... It all depends on how they managed to get their ratings.
Some manufacturers (Dyns for eg.) play for 100 hours and then increases by 6dB in order to rate their drivers.
Others' (JL Audio for eg.) power ratings are made for a speaker to play at their spec'd power for 8 hours continously - it used to be conservative but now are much closer to how others rate/find their RMS. Good read... and here and another

As you can see RMS ratings are just here to fool us into thinking one driver handles more when we are actually not comparing apples to apples ;)

Regarding power ratings, here's a good read
Some use AES, others use IEC and a lot use "I don't know what kind of method" :laugh:

Kelvin
 

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I'm not arguing, just learning. :D

What's the price on the SL?
Dunno... I got my SL10 for free :D My cousin was a dealer but closed down.
After plotting a few subs that was actually the one I wanted that was giving me the best performance for the small enclosure I was making...

Used to be around $200 if I remember correctly... It has been discontinued though for whatever reason :(

Kelvin
 

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All we have to go off is the specs at this point. So why not assume all the specs are false?

And at almost 5" mounting depth is it that hard to believe the Polk can't do 12mm?

Besides, my last two post were in reference to the polks vs. the RE SLs.
Only a small fraction of the subs we tested hit 12mm at a true 10% distortion threshold. Think that the mighty JBL differential drives only managed 8mm or so. How deep are those, a foot? I do assume all specs are false. I even bought and sent speakers to Erin to get them Klippel tested before using them. There is too much smoke in this industry to make useful decisions. Alpine posted that Klippel result on their website because they know there is no slim sub with that kind of performance out there. There also isn't a slim sub with that kind of mechanical throw.

That brings me to another point. When you simulate subs in WinISD you have to know the true xmax performance of each driver to know how much you can push them. There are other things as well like motor noise (the reason I won't buy RE products anymore) and voice coil performance that won't be reflected in T/S specs.
 

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By voice coil performance you mean thermal capabilities?
Yep, and with it the effects of compression on T/S parameters, just like how the T/S parameters move about under excursion due to motor, suspension and inductance nonlinearities. Simulations only hold given the parameters don't change at all. In fact they do,starting with the first watt, so if you start modeling hundreds of watts the results could be quite different from real life.

I used a set of Polk Momos, they were my first subs. All in all I think Polk is quite mediocre. There was a bit of motor noise and the cones seemed to maybe flex a bit under high excursion. It was painfully obvious they were not very linear, the rise in Q with excursion was very audible. It was as if under more power they sounded boomy or lost steam (Q goes up and motor force drops). So when they claim 25mm of xmax with these new subs I just don't buy it. They seem to use the Klippel moniker in the same way car manufacturers use the Nurburgring to build company image. Few of the cars actually get revisions with a pro car driver at the Ring, they merely roll on the track once or twice. I did that too, doesn't mean I perfected the vehicle dynamics.
 

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Yep, and with it the effects of compression on T/S parameters, just like how the T/S parameters move about under excursion due to motor, suspension and inductance nonlinearities. Simulations only hold given the parameters don't change at all. In fact they do,starting with the first watt, so if you start modeling hundreds of watts the results could be quite different from real life.

I used a set of Polk Momos, they were my first subs. All in all I think Polk is quite mediocre. There was a bit of motor noise and the cones seemed to maybe flex a bit under high excursion. It was painfully obvious they were not very linear, the rise in Q with excursion was very audible. It was as if under more power they sounded boomy or lost steam (Q goes up and motor force drops). So when they claim 25mm of xmax with these new subs I just don't buy it. They seem to use the Klippel moniker in the same way car manufacturers use the Nurburgring to build company image. Few of the cars actually get revisions with a pro car driver at the Ring, they merely roll on the track once or twice. I did that too, doesn't mean I perfected the vehicle dynamics.
That makes sense, I read a great quote once (I wish a could remember who said it, it was someone credible) it went, "if a speaker moves, it distorts, point blank".

For the record I never thought the Polks were top of the line speakers. I just think they are probably very capable for the price. I got my 2 12s for $240 shipped, I haven't seen anything else comparible for that much money. If I could afford it I'd definitely go with JL's 13TW5, Alpine's type R, or some BM MKIIIs.
 

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But, the evidence still doesn't show that the polks can't get as loud as any of the other speakers mentioned.

The specs may not be entirely accurate and the polks may not be the best SQ sub, but they are still a contender as far as the thread topic is concerned.
 

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What BL and MMS did you use to model the Alpine? I can't find them anywhere.
For the SWR-T10, WinISD calculates the MMS to be 203.6 and BL to be 16.61377
For the SWR-T12, the MMS is 255.3 and the BL is 16.2329

Hope that helps,
Kelvin
 

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I just received my alpine swr-t10 a couple days ago to test out..so far im loving it...gets down pretty low and the output is enough for me...I installed it in a .3 cu ft box too =) with fiberglass insulation and a little polyfill of course.

I have owned numerous shallow subs...and the alpine are one my top list. Blended real well with my front stage.
 
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