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post #181 of 661 Old 05-07-2009, 03:05 PM
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Could one actually use one of these subs as an end table?

They are simply stunning--would love to hear one.

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post #182 of 661 Old 05-07-2009, 03:58 PM - Thread Starter
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Quote:
Originally Posted by noah katz View Post

"I'm using 100Hz for the current tests."

Interesting.

Any idea how the Maelstrom-X compares?

Dual 15" advantages:

1. Dual opposing drivers = less vibration
2. Dual 15s = 19% more Vd
3. Dual drivers = 1.5dB higher sensitivity
4. Dual drivers = more power handling
5. Dual drivers = less excursion for same output = less non-linear distortion

Maelstrom-X advantages:

1. It costs less
2. It weighs less
3. 1 less hole to cut

All of the SQ advantage goes to the dual opposed Tumults.

Bosso
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post #183 of 661 Old 05-07-2009, 04:06 PM - Thread Starter
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Quote:
Originally Posted by mziegler View Post

Could one actually use one of these subs as an end table?

They are simply stunning--would love to hear one.

Absolutely. I get to watch the driver handle business and the wife gets to set a lamp on the glass. We're both happy.

I appreciate the compliment.

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Originally Posted by jxhopper View Post

Wow. Excuse me while I pick my jaw up off the floor and out of the puddle of slobber

Hah. I'm way past the jaw/slobber phase, but I sure never get tired of looking at them. Like most audio equipment, pictures don't do them justice.

Still testing. I'll get back to you the first of next week, if that's OK.

Bosso
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post #184 of 661 Old 05-08-2009, 03:14 PM - Thread Starter
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Posting some measurements results...

First, this verifies what I've been saying for years. The Raven vs the Bamboo subs: They both have identical drivers, the signal chain is identical, the sub and mic positions were identical the signal level was identical.

The only difference is that the Bamboo sub is in a 50% larger enclosure. As the measurements verify, there is a penalty of a couple of dB below the knee and a gain of around 1dB above the knee and the larger sub has a slightly lower anechoic system Q.

The difference in Air Spring Distortion difference is solved by a secret.

The point is that the differences can be easily equalized by the L/T. The question remains if there is any discernible SQ difference.

Here's both subs, anechoic:


Here's both subs, before and after final L/T:


Just for an example of how versatile the adjustable L/T is, here is the Raven in final L/T config with 6dB, 8dB, 10dB and 12dB boost settings, taking less than one second to set each boost setting and keeping in mind that the system Q can also be changed (not shown in this graph) just as quickly:


Bosso
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post #185 of 661 Old 05-08-2009, 05:28 PM
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"All of the SQ advantage goes to the dual opposed Tumults."

I forgot the Tumult's were 15's.

To rephrase the question, how do you think an equal number of Mael's would compare for midbass punch?

Noah
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post #186 of 661 Old 05-08-2009, 10:39 PM - Thread Starter
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Quote:
Originally Posted by noah katz View Post

"All of the SQ advantage goes to the dual opposed Tumults."

I forgot the Tumult's were 15's.

To rephrase the question, how do you think an equal number of Mael's would compare for midbass punch?

That's a good question. On paper, it should be pretty equal, but I haven't seen a single measurement of the M-X to venture anything but a guess.

Bosso
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post #187 of 661 Old 05-08-2009, 10:44 PM
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Ricci posted a close mic of a Mal-X, as well as a few other subs.

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post #188 of 661 Old 05-08-2009, 11:44 PM - Thread Starter
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Quote:
Originally Posted by michael hurd View Post

Ricci posted a close mic of a Mal-X, as well as a few other subs.

Where? It's news to me. I know there was a Mael-X at the wisconsin G2G, but I didn't see any measurements?

Heads up? Ricci, you out there?

Bosso
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post #189 of 661 Old 05-09-2009, 01:08 PM
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Page 11 on the GTG thread here: http://www.avsforum.com/avs-vb/showt...111483&page=11

"You take the blue pill - the story ends, you wake up in your bed and believe whatever you want to believe. You take the red pill - you stay in Wonderland and I show you how deep the rabbit-hole goes."
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post #190 of 661 Old 05-09-2009, 01:57 PM - Thread Starter
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Quote:
Originally Posted by michael hurd View Post

Page 11 on the GTG thread here: http://www.avsforum.com/avs-vb/showt...111483&page=11

Thanks, but those are seriously tainted measurements. The sealed M-X doesn't have an F3 of 18Hz. Judging by the LP roll off, it looks like the Tumult MKII has a 5-6dB advantage in the mid bass, but I wouldn't go by that measurement.

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post #191 of 661 Old 05-09-2009, 02:21 PM
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Quote:
Originally Posted by bossobass View Post

Thanks, but those are seriously tainted measurements. The sealed M-X doesn't have an F3 of 18Hz. Judging by the LP roll off, it looks like the Tumult MKII has a 5-6dB advantage in the mid bass, but I wouldn't go by that measurement.

Bosso

Keep in mind this was in a larger room, around 3000 cu ft or so, and I don't believe any of the subs had the benefit of corner loading, you can ask Ricci and Warpdrv about it.

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post #192 of 661 Old 05-09-2009, 03:51 PM
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Room size was mispoken, and is only 2300^3 or so, and here's a link to the position of the sub in the room.... http://www.avsforum.com/avs-vb/showt...9#post15942219

the mal-x is at the bottom of the stack
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post #193 of 661 Old 05-09-2009, 06:38 PM - Thread Starter
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Quote:
Originally Posted by michael hurd View Post

Keep in mind this was in a larger room, around 3000 cu ft or so, and I don't believe any of the subs had the benefit of corner loading, you can ask Ricci and Warpdrv about it.

No need to ask if the sub benefitted by room gain. There's simply no way the M-X has a 13dB advantage at 20Hz. Even with the 12dB L/T boost the M-X still shows a 7dB advantage at 20Hz and an F3 of 18Hz with no L/T.

The M-X F3 should be close to the Tumult, it should be down 8-10dB at 20Hz and 20-22dB down at 10Hz.

To address Noah's question, the M-X measurement shows it's down 12dB at 100Hz with a 100Hz 4th order LP. That would indicate that the M-X is down 4-6dB at 100Hz with no LP.


Bottom line is that Ricci's measurement shows a huge amount of room influence, completely masking the actual anechoic response.

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post #194 of 661 Old 05-09-2009, 06:52 PM
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Quote:
Originally Posted by bossobass View Post

No need to ask if the sub benefitted by room gain. There's simply no way the M-X has a 13dB advantage at 20Hz. Even with the 12dB L/T boost the M-X still shows a 7dB advantage at 20Hz and an F3 of 18Hz with no L/T.

The M-X F3 should be close to the Tumult, it should be down 8-10dB at 20Hz and 20-22dB down at 10Hz.



Bottom line is that Ricci's measurement shows a huge amount of room influence, completely masking the actual anechoic response.

Bosso


I agree 100% Bosso, most def room gain involved with all measurements taken there and no added EQ either.... I would love to see ground plane measures on them myself.

As stated many times before, in even close mic samples in room don't reflect the true output of a driver... to much room interaction.

Here is another close mic of the Mal-X and the F112, corner loaded (no EQ) when Nuance and I were doing a comparo of the two, just for measurements sake, not to poison your thread here buddy... didn't know if you saw this one.

http://www.avsforum.com/avs-vb/showp...&postcount=110
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post #195 of 661 Old 05-09-2009, 07:16 PM
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Bosso, is there somewhere around you to measure the driver in an anechoic chamber? You do realize that unless you have a *very* large anechoic chamber results under 100hz are largely influenced by the room, even if you have many feet of absorbtion.

Or is that measurement labeled anechoic an outdoor measurement GP?

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post #196 of 661 Old 05-09-2009, 07:38 PM - Thread Starter
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Quote:
Originally Posted by Warpdrv View Post

I agree 100% Bosso, most def room gain involved with all measurements taken there and no added EQ either.... I would love to see ground plane measures on them myself.

As stated many times before, in even close mic samples in room don't reflect the true output of a driver... to much room interaction.

Here is another close mic of the Mal-X and the F112, corner loaded (no EQ) when Nuance and I were doing a comparo of the two, just for measurements sake, not to poison your thread here buddy... didn't know if you saw this one.

http://www.avsforum.com/avs-vb/showp...&postcount=110

No problem, I appreciate the input.

Actually, your measurements offer better insight. Since we know the JL is dead flat anechoic from 50-100Hz, the comparison indicates the M-X is down around 3dB at 100Hz, anechoic, which is virtually the same as the Tumult MKII.

They should be very hard to tell apart in the mid bass, is my guess.

The listening tests of the various drivers in varying sizes of box, all L/Td to very close to the same anechoic response and placed in the identical spot in the room will be interesting,

The only difference besides the drivers is that the new Bamboo sub is 4" taller, placing the top driver higher in the room. My son has already said that he hears a definite difference.

I plan to compare peak hold graphs of the subs to see if there are any differences there while the listening/subjective comments are happening.

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post #197 of 661 Old 05-09-2009, 07:49 PM - Thread Starter
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Quote:
Originally Posted by michael hurd View Post

Bosso, is there somewhere around you to measure the driver in an anechoic chamber? You do realize that unless you have a *very* large anechoic chamber results under 100hz are largely influenced by the room, even if you have many feet of absorbtion.

Or is that measurement labeled anechoic an outdoor measurement GP?

It doesn't have to done outdoors to be accurate. Here's an indoor of the Tumult MKI (and other drivers) I did a couple of years before Ilkka measured the same box size/driver at 2M GP. Other than the 2 anomalies, the responses are virtually identical.

Since I took this measurement, I've honed the technique a bit more (virtually none of the anomalies caused by the rooms boundaries). I believe the results lie more in the measurement rig and technique and not so much in the environment.



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post #198 of 661 Old 05-10-2009, 12:12 PM
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Quote:
Originally Posted by bossobass View Post

No problem, I appreciate the input.

Actually, your measurements offer better insight. Since we know the JL is dead flat anechoic from 50-100Hz, the comparison indicates the M-X is down around 3dB at 100Hz, anechoic, which is virtually the same as the Tumult MKII.

They should be very hard to tell apart in the mid bass, is my guess.




Bosso


Also please note that I believe that those measurements are likely crossed over at 80hz, I think we should have raised the xover to get more realistic measurements, so that likely had some input on why its lower on the top end.

Def. not a regular practice of mine, so I haven't gotten to the point of being able to provide proper measurements here...

FWIW From a listening standpoint, the F112 and Mal-X are almost identical in sonic qualities.... both extremely excellent drivers IMO
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post #199 of 661 Old 05-10-2009, 05:10 PM
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Quote:
Originally Posted by bossobass View Post

Where? It's news to me. I know there was a Mael-X at the wisconsin G2G, but I didn't see any measurements?

Heads up? Ricci, you out there?

Bosso

Quote:
Originally Posted by michael hurd View Post

Page 11 on the GTG thread here: http://www.avsforum.com/avs-vb/showt...111483&page=11

Quote:
Originally Posted by bossobass View Post

Thanks, but those are seriously tainted measurements. The sealed M-X doesn't have an F3 of 18Hz. Judging by the LP roll off, it looks like the Tumult MKII has a 5-6dB advantage in the mid bass, but I wouldn't go by that measurement.

Bosso

Sorry, I been out of town gigging for a few days. Bosso is right. I wouldn't really compare those graphs to anything else. They are in room, there is an xover engaged and they were really quick. I didn't have enough dedicated time with the Mal-x's to offer any informed opinion. I wish I did. You know, it is a bit amazing that with all of those drivers that have been bought there isn't very much that has been posted for them from a measurement perspective. Has there been a solid un filtered close mic posted by anyone?
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post #200 of 661 Old 05-11-2009, 12:06 AM
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But do people think midbass punch is predictable just w/measurements?

I hate to venture into "fast bass" territory, but if it were that simple you'd just need to EQ up any rolloff, assuming enough output capability.

I'm referring to LTD, or LHD, or somebody w/3 initials starting w/L, saying the Mal's couldn't quite match good pro drivers.

And another other fly in the ointment of complexity - I thought it was supposed to be helped by clean upper bass from low flux modulation by virtue of shorting rings.

But most pro woofers don't have them, right?

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post #201 of 661 Old 05-11-2009, 12:20 AM
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Having high motor strength definately helps out in the midbass region, look for a raw driver that has high electromagnetic damping. ( as most pro drivers do ) You can have decent midbass with a heavy cone, provided the motor has a lot of power to exude control over the cone.

I am not sure as to which pro drivers have inductance countermeasures ( shorting rings/ sleeves ) but many have much shorter coils and less inductance than your typical overhung subwoofer driver.

High qes ( low electrical damping ) can sort of act like a car with worn out shocks driven over washboard.

A simple frequency response curve won't tell you if a certain driver has good midbass or not, they are usually a slow swept sine wave with many samples.

Inductance is not the be all and end all of midbass. Assuming the inductance varies little with cone displacement and amperage through the coil, you can have decent midbass. Inductance is simply a low pass filter in the simplist sense.

If you have major fluctuations in the inductance, you will have other issues arise.

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post #202 of 661 Old 05-11-2009, 02:30 AM
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Quote:
Originally Posted by noah katz View Post

But do people think midbass punch is predictable just w/measurements?

I hate to venture into "fast bass" territory, but if it were that simple you'd just need to EQ up any rolloff, assuming enough output capability.

I'm referring to LTD, or LHD, or somebody w/3 initials starting w/L, saying the Mal's couldn't quite match good pro drivers.

lol, don't shoot the messenger man. ;-)

pete hsu arrived at the same conclusion in his work, hence the hsu mbm.

i suspect it is an efficiency and damping matter. subjective reports seem to correlate with high efficiency (97db+) as well as low qes (<0.31 or so).

Quote:


And another other fly in the ointment of complexity - I thought it was supposed to be helped by clean upper bass from low flux modulation by virtue of shorting rings.

But most pro woofers don't have them, right?

the higher end pro guys all seem to incorporate shorting rings in their designs. i have seen them used in b&c (as in the ones geddes uses), jbl (2226h, the one parham uses, and others), rcf, 18sound, and bms off the top of my head.

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post #203 of 661 Old 05-11-2009, 02:34 AM
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Quote:
Originally Posted by michael hurd View Post

Having high motor strength definately helps out in the midbass region, look for a raw driver that has high electromagnetic damping. ( as most pro drivers do ) You can have decent midbass with a heavy cone, provided the motor has a lot of power to exude control over the cone.

I am not sure as to which pro drivers have inductance countermeasures ( shorting rings/ sleeves ) but many have much shorter coils and less inductance than your typical overhung subwoofer driver.

High qes ( low electrical damping ) can sort of act like a car with worn out shocks driven over washboard.

A simple frequency response curve won't tell you if a certain driver has good midbass or not, they are usually a slow swept sine wave with many samples.

Inductance is not the be all and end all of midbass. Assuming the inductance varies little with cone displacement and amperage through the coil, you can have decent midbass. Inductance is simply a low pass filter in the simplist sense.

If you have major fluctuations in the inductance, you will have other issues arise.

+1! holy crap. somebody who agrees with me! go mike!

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post #204 of 661 Old 05-11-2009, 02:38 AM
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another point is the impedance locus. in most home subs, it is in the thirties, which is perfect for producing bass from 20-50hz or so. however, it drops quickly in the upper bass, so big current is required to pound out the upper bass (50-150hz).

most pro audio woofs have an inbox impedance locus in the 50-100hz region, hence minimal amp current is required to punch out maximal spl in that region.

this is validated in the frequency sweeps provided by ilkka. you can see compression hitting the home style subs in the upper bass before the lower bass.

just another nugget to throw into the mix.

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post #205 of 661 Old 05-11-2009, 02:46 AM
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Also, to add, a pro style driver has typically very tight gaps, and can shed heat quickly, this is also why they have less thermal compression in the mid bass area, leading to good transients. ( as well as the higher sensitivity from the get-go )

Compare that to the monster wide gap on an LMS 5400 or RE XXX, and you will see that to excel on one area means some comprimise in another. Obviously you wouldn't use a RE XXX for 50-150 hz, nor would you select a JBL 2226 for subwoofer duty. It's just not the right tool for the job.

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post #206 of 661 Old 05-11-2009, 02:51 AM
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Quote:
Originally Posted by michael hurd View Post

Also, to add, a pro style driver has typically very tight gaps, and can shed heat quickly, this is also why they have less thermal compression in the mid bass area, leading to good transients. ( as well as the higher sensitivity from the get-go )

Compare that to the monster wide gap on an LMS 5400 or RE XXX, and you will see that to excel on one area means some comprimise in another. Obviously you wouldn't use a RE XXX for 50-150 hz, nor would you select a JBL 2226 for subwoofer duty. It's just not the right tool for the job.

ok, i want to agree with this with another giant "+1", but let's see some data first.

what are the gaps on the lms, re, and jbl for comparison?

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post #207 of 661 Old 05-11-2009, 03:17 AM
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Found on the lansing herirage site: "The 2226 uses the Vented Gap Cooling Motor with the 0.069" gap." It uses an edgewound ribbon VC.

The LMS has a 4" linear coil, with round wire which has more windings near the outer ends ( think hourglass shaped ) and the winding length is just about 3" or so. ( I don't have one apart at the moment ) The gap is pretty large. Maybe Kyle can chime in on how large it is.

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post #208 of 661 Old 05-11-2009, 03:43 AM
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Ricci's XXX 18 apart: http://www.hometheatershack.com/foru...-xxx-18-a.html

Take a look how wide the gap is in the motor and how thick the coil is. Then multiply that by the fact that it's capable of 54 mm throw, and a bit more before it comes up short on the back of the motor.

Massive! Obviously it's not running on a 6 thou gap, as the amount of power it will handle will cause the coil to change in diameter a lot. Probably 30+ thou on the outside of the coil to the inside of the gap plate.

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post #209 of 661 Old 05-11-2009, 03:47 AM
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LMS 5400 gap:

LMS 5400 coil:
LL
LL

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post #210 of 661 Old 05-11-2009, 04:12 AM - Thread Starter
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Quote:
Originally Posted by noah katz View Post

But do people think midbass punch is predictable just w/measurements?

I hate to venture into "fast bass" territory, but if it were that simple you'd just need to EQ up any rolloff, assuming enough output capability.

Yes, midbass punch is predictable with just measurements. Of course, this assumes a minimum of performance requirements are met, but take any subwoofer that's flat through the crossover and A/B it with and without a 40Hz HP filter.

Looking at the Tumult MKI graphs above, you see a 10dB drop from 40Hz to 100Hz. That's 7dB/octave. If you use a typical 4th order LP and cross at the typical 80Hz point, you're LP side is better than 5th order vs the typical 2nd order HP, which is made shallower by room gain going down.

That's not likely to be fixed by EQ. The 'fix' was to lower the crossover to a point where the driver was designed to be operated in. This left the midbass to the mains. Whether or not mains are capable, their placement restrictions almost always results in a wanting response in the 100-200Hz BW.

This lower crossover point requirement was reinforced by the audiophiles who insisted that any sub crossed higher than 40Hz would be localized.

The latest generation of XBl^2 HT subs (Tumult MKII, Mael-X, Shiva-X) employ shorting rings to lower inductance which allows for a higher crossover point.

But, any sub with an octave or 2 more extension will sound different from a pro sound driver. Efficiency has nothing to do with it.

Ilkka's sweeps of the Tumult MKI show a 10% THD limited output at 80Hz of around 92dB with less that 1dB of compression, but the CEA test result is 111dB at 80Hz. That's at 2M. At 1M, where all pro sound drivers list their 'specs' it would be 117dB.

That's plenty of clean output to judge midbass in a home. It just isn't realized when you lower the crossover point and try to match a Tumult with not-so-good mains.

Bosso
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