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post #1 of 142 Old 11-14-2013, 11:25 AM - Thread Starter
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Hi all,

I've been poking around here for weeks (bad idea, budget has already almost doubled lol) looking into subs for my system. I've got Polk RTI A9's, CSi A6, and F/Xi A6's for surrounds and I'm looking at upgrading my receiver to a Denon X4000. I've attached a diagram of my living room layout, it's a little bigger than 24'x19'x8' or around 3600cuft with hardwood floors. There is a large opening w/ 2 french doors leading into the dining room and kitchen that is probably around 8-10ft. The purple squares are my speakers, the green boxes are possible sub locations with location B as an optional spot for the sub in location A during December when I put a Christmas tree in that spot. The Sub 1 spot has been wired in-wall already. I'm pretty much a novice when it comes to audio, outside of volume and crossover freq, I have no idea about the other knobs on the back of these higher end subs and what they do haha. I'm a technical guy, so I'm hoping once I have more time I can learn about this stuff.

My budget is now around $1000-$1500. I only spent around $1000 for my speakers so I don't want to go to much more than that for sub(s), and if I can get by with staying close to $1000, I'd like to. Right now I'm 90% movies/games and 10% music; but I do like soundtracks, so I'm not sure if listening to a movie OST during the movie falls under music or movies haha. Given the room size and listening habits I'm assuming I should go for ported subs over sealed. So far i've been looking at:

2 x Outlaw LFM1-EX
1 or 2 x PSA XV-15
1 x HSU VTF-15h
1 x Rythmik FV15HP

I can't say 100% but I'm 80% sure I will not be picking up a 2nd sub expensive sub for at least 4-5 years as I'm living in a foreclosure and most of my cash is going into the house itself. Additionally I may be in a different house with a different room at that time as well. I've looked at the build your own kits, and while I think I'd be fine putting them together, I'm worried about rattles and other issues that I may not know how to solve as a novice (they are also seem to be out of stock of almost everything for the next month or 2).


So would I be ok with 1 bigger sub or is the current room big and strange enough to warrant 2 medium subs now? Would 2 XV-15's be worth the extra $400 or so over 2 LFM1-EX's (I've read threads that they are pretty close in output)?

I appreciate any advise and insight!

LEAD Technologies Inc. V1.01
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post #2 of 142 Old 11-14-2013, 11:59 AM
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Based on the info on Data-Bass.com, I'd go with dual LFM-1 EXs, run them in one-port mode, and pocket the $400 difference.
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post #3 of 142 Old 11-14-2013, 12:31 PM - Thread Starter
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Thanks, that site is interesting. I'm assuming the numbers are output measured in DBs? I'm not sure I'd be able to identify what 1 extra DB would sound like.
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post #4 of 142 Old 11-14-2013, 12:50 PM
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Yes, it's output in decibels (dB), measured at 2m ground-plane (IIRC). The 4.2dB difference at 50Hz might be noticeable if you were A/B-ing the subs but, in practical terms:
- you won't notice it;
- it's the largest measured disparity between the two subs in the 16-125Hz range - at all other frequencies, the performance of the LFM-1 EX is closer to that of the XV15; and
- the LFM-1 EX can still output 112.4dB at that frequency, so it's not exactly a slouch. smile.gif
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post #5 of 142 Old 11-14-2013, 02:26 PM
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Tough call. I'd probably go with either the dual PSA XV15 or single Rythmik FV15HP.
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post #6 of 142 Old 11-14-2013, 02:27 PM
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Originally Posted by rnatalli View Post

Tough call. I'd probably go with either the dual PSA XV15 or single Rythmik FV15HP.

+1. These would be the options I would look at.
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post #7 of 142 Old 11-14-2013, 03:12 PM
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The Outlaw subs would not be $400 cheaper than the XV15 subs. They are about the same price when you factor in shipping, but you might ask Outlaw on cutting you a deal for a pair. They might be around $600 shipped each on Black Friday if there is a particularly good sale, Outlaw is known for its great sales. You might consider dual Hsu VTF3s. They are a basically improved Outlaw EXs. Better ports, slightly improved driver, and an additional Q control feature, and at nearly the same price as a pair of EXs. Hsu designed the Outlaw subs and the VTF3 mk4s are a generation ahead. If the Outlaw is actually $1200 a pair on Black Friday, that is a worthwhile deal, but at the same price, the VTF3 is easily the better choice. If you don't need a sub right away. Personally, I would wait for the Dayton Titanic 4 15" kit, it won't quite match any of them at 20 Hz, but it will kill them all above 30 Hz.
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post #8 of 142 Old 11-14-2013, 10:25 PM
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Originally Posted by eljaycanuck View Post

Based on the info on Data-Bass.com, I'd go with dual LFM-1 EXs, run them in one-port mode, and pocket the $400 difference.

Where did you drum up this blasphemy? Or did you mean 40.00 difference??

Dual LFM-1EX's are 1477.71 shipped

Dual PSA XV15's are 1518.10 shipped
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post #9 of 142 Old 11-14-2013, 10:31 PM
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Originally Posted by Warder45 View Post

Hi all,

I've been poking around here for weeks (bad idea, budget has already almost doubled lol) looking into subs for my system. I've got Polk RTI A9's, CSi A6, and F/Xi A6's for surrounds and I'm looking at upgrading my receiver to a Denon X4000. I've attached a diagram of my living room layout, it's a little bigger than 24'x19'x8' or around 3600cuft with hardwood floors. There is a large opening w/ 2 french doors leading into the dining room and kitchen that is probably around 8-10ft. The purple squares are my speakers, the green boxes are possible sub locations with location B as an optional spot for the sub in location A during December when I put a Christmas tree in that spot. The Sub 1 spot has been wired in-wall already. I'm pretty much a novice when it comes to audio, outside of volume and crossover freq, I have no idea about the other knobs on the back of these higher end subs and what they do haha. I'm a technical guy, so I'm hoping once I have more time I can learn about this stuff.

My budget is now around $1000-$1500. I only spent around $1000 for my speakers so I don't want to go to much more than that for sub(s), and if I can get by with staying close to $1000, I'd like to. Right now I'm 90% movies/games and 10% music; but I do like soundtracks, so I'm not sure if listening to a movie OST during the movie falls under music or movies haha. Given the room size and listening habits I'm assuming I should go for ported subs over sealed. So far i've been looking at:

2 x Outlaw LFM1-EX
1 or 2 x PSA XV-15
1 x HSU VTF-15h
1 x Rythmik FV15HP

I can't say 100% but I'm 80% sure I will not be picking up a 2nd sub expensive sub for at least 4-5 years as I'm living in a foreclosure and most of my cash is going into the house itself. Additionally I may be in a different house with a different room at that time as well. I've looked at the build your own kits, and while I think I'd be fine putting them together, I'm worried about rattles and other issues that I may not know how to solve as a novice (they are also seem to be out of stock of almost everything for the next month or 2).


So would I be ok with 1 bigger sub or is the current room big and strange enough to warrant 2 medium subs now? Would 2 XV-15's be worth the extra $400 or so over 2 LFM1-EX's (I've read threads that they are pretty close in output)?

I appreciate any advise and insight!

LEAD Technologies Inc. V1.01
I'm looking to sell my XV15, if you go that route. PM me and we can talk.
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post #10 of 142 Old 11-14-2013, 10:42 PM
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Originally Posted by eljaycanuck View Post

Yes, it's output in decibels (dB), measured at 2m ground-plane (IIRC). The 4.2dB difference at 50Hz might be noticeable if you were A/B-ing the subs but, in practical terms:
- you won't notice it;
- it's the largest measured disparity between the two subs in the 16-125Hz range - at all other frequencies, the performance of the LFM-1 EX is closer to that of the XV15; and
- the LFM-1 EX can still output 112.4dB at that frequency, so it's not exactly a slouch. smile.gif

The XV15 has a greater advantage then that when you factor in the correction for the mic placement in relation to the driver when the XV15 was tested. The LFM-1 was laid on its side with the driver facing the mic. The XV15 had the base plate blocking the driver from the mic. In room where the bass can reflect would negate the placement difference, but in a 2m open ground plane enviroment there is a difference. Not taking away anything from the LFM-1 as its a great sub, but the data-bass XV15 numbers can not be fairly compared to other subs.

This is a prime example why. Look at HSU VTF-3 cea2010 numbers and then look up the XV15 cea2010 numbers.

VTF-3 20-31hz = 115db, 40-63hz = 121db

XV15 20-31hz = 117db, 40-63hz = 125db

The VTF-3 is slightly more powerful then the LFM-1. Also small updates have been done to the XV15 since it was tested that improved performance slightly.

All that being said of you can go with a Rythmik FV15HP now and add another down the road, thats the route I would go!!
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post #11 of 142 Old 11-15-2013, 12:20 AM
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Originally Posted by basshead81 View Post

The XV15 has a greater advantage then that when you factor in the correction for the mic placement in relation to the driver when the XV15 was tested. The LFM-1 was laid on its side with the driver facing the mic. The XV15 had the base plate blocking the driver from the mic. In room where the bass can reflect would negate the placement difference, but in a 2m open ground plane enviroment there is a difference. Not taking away anything from the LFM-1 as its a great sub, but the data-bass XV15 numbers can not be fairly compared to other subs.

This is a prime example why. Look at HSU VTF-3 cea2010 numbers and then look up the XV15 cea2010 numbers.

VTF-3 20-31hz = 115db, 40-63hz = 121db

XV15 20-31hz = 117db, 40-63hz = 125db

The VTF-3 is slightly more powerful then the LFM-1. Also small updates have been done to the XV15 since it was tested that improved performance slightly.

All that being said of you can go with a Rythmik FV15HP now and add another down the road, thats the route I would go!!

On the XV15, if you have the woofer facing the mic, then you have the port facing away from the mic, so by that reasoning you have to subtract port contribution to output by as much as you add woofer contribution. You also have to consider the additional distortion which is masked by having the woofer facing away from the mic. That factor might actually have lowered some measurements for the XV15 were the tests done with the woofer facing the mic. Contrary to your above statement, you could not ask for a fairer comparison of subs than data-bass's testing. But you can only fairly use data-bass's measurements against other data-bass measurements, and they haven't measured the VTF3. Hsu may have adhered to the CEA2010 standard in their measurements, but it has been shown repeatedly that CEA2010 is not a rigorous enough standard to make a decibel-to-decibel comparison, so you can use the Outlaw's numbers with more confidence given they are from the same data set, but comparing the VTF3 to the XV15 involves a greater degree of speculation. Besides that, CEA2010 only tells part of the story about subwoofer performance and CEA averages tells even less.
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post #12 of 142 Old 11-15-2013, 12:49 AM
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Most likely for home theater use they will be practically even.

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post #13 of 142 Old 11-15-2013, 06:05 AM
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Where did you drum up this blasphemy?
The "blasphemy"... rolleyes.gif ...was based on this line from the OP's first post:
Quote:
Would 2 XV-15's be worth the extra $400 or so over 2 LFM1-EX's ... ?
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post #14 of 142 Old 11-15-2013, 06:33 AM
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Originally Posted by shadyJ View Post

On the XV15, if you have the woofer facing the mic, then you have the port facing away from the mic, so by that reasoning you have to subtract port contribution to output by as much as you add woofer contribution.
Having the port or cone facing away from the mic, or the listener, is moot, since the output of a port, and from the cone, within the sub woofer pass band is omni-directional. That's assuming that proper measuring protocol was followed, which means measuring from no less than 2 meters away, or if measured nearfield that the two results were properly combined. Where THD is concerned that will be lower if the mic is not facing the cone, as the above bandwidth harmonics that are components of the THD figure aren't omni-directional.

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post #15 of 142 Old 11-15-2013, 07:08 AM
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Originally Posted by shadyJ View Post

On the XV15, if you have the woofer facing the mic, then you have the port facing away from the mic, so by that reasoning you have to subtract port contribution to output by as much as you add woofer contribution. You also have to consider the additional distortion which is masked by having the woofer facing away from the mic. That factor might actually have lowered some measurements for the XV15 were the tests done with the woofer facing the mic. Contrary to your above statement, you could not ask for a fairer comparison of subs than data-bass's testing. But you can only fairly use data-bass's measurements against other data-bass measurements, and they haven't measured the VTF3. Hsu may have adhered to the CEA2010 standard in their measurements, but it has been shown repeatedly that CEA2010 is not a rigorous enough standard to make a decibel-to-decibel comparison, so you can use the Outlaw's numbers with more confidence given they are from the same data set, but comparing the VTF3 to the XV15 involves a greater degree of speculation. Besides that, CEA2010 only tells part of the story about subwoofer performance and CEA averages tells even less.

Ricci even said there is a difference...its not alot but there is. I know its tough for you to swallow as we have had this conversation multiple times but it is what it is. You say CEA2010 is not good enough but the HSU VTF-15 numbers match up well with data-bass...S&V numbers are close with Data-Bass on both the PC12 and XV15. My point with all that is you can see there is around a 1-1.5db difference with XV15.

Aside from all that I would go with a FV15HP anyhow.
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post #16 of 142 Old 11-15-2013, 07:09 AM
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Originally Posted by eljaycanuck View Post

The "blasphemy"... rolleyes.gif ...was based on this line from the OP's first post:

Thats still Blasphemy as 2 XV15's are worth every penny over the Outlaw.
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post #17 of 142 Old 11-15-2013, 07:21 AM
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Thats still Blasphemy as 2 XV15's are worth every penny over the Outlaw.
If you say so.
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post #18 of 142 Old 11-15-2013, 07:25 AM - Thread Starter
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Thanks for all the info! I should have probably said, as a deal hunter I'd probably only go with the LFM-1 EX if they have another sale like last year with it dropping to $600 and Free Shipping. That puts it about $300 cheaper than dual XV15's, otherwise I'd probably just step up to the XV15's. Another option I didn't consider would be 2 Rythmik LV12R's which would come out to around $1200 as well. I'd only be worried about the rear port, since they would only have 6" at most of clearance from the wall.

I'd love to do dual FV15HP's but even if I had the money down the road, I'd have a hard time spending $2500 on subs when i only spent $1200 on speakers and $1500 on a receiver. Of course I didn't think I'd buy my car after leasing it or buy a house either lol.

Sounds like 2 x XV15 or 1 FV15HP is the way to go, any reason the FV15HP is recommended more that the HSU VTF-15h? Also, this might be a strange question but are there any power/electrical issues I should be aware of as I'd have my AVR, TV, game systems, and subs all on the same circuit?
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post #19 of 142 Old 11-15-2013, 07:27 AM
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Another thing I would like to touch up on. I like how some you love to compare a variable tuning subs and only look at its max output mode for compression and THD. Look at the LFM-1 EX in 1 port mode. Ricci could not perform a 115db sweep, it has more compression @ 110db, and its THD is greater. When you look at the XV15 110db(NOT the 115db) sweep it maintains great composure and relatively low THD. Yes the XV15 has higher Second Order THD, but Ricci even states its the most benign of harmonics and preferred by some subjectively.


Again that being said, The FV15HP would be my choice.
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post #20 of 142 Old 11-15-2013, 07:47 AM
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Originally Posted by Warder45 View Post

Thanks for all the info! I should have probably said, as a deal hunter I'd probably only go with the LFM-1 EX if they have another sale like last year with it dropping to $600 and Free Shipping. That puts it about $300 cheaper than dual XV15's, otherwise I'd probably just step up to the XV15's. Another option I didn't consider would be 2 Rythmik LV12R's which would come out to around $1200 as well. I'd only be worried about the rear port, since they would only have 6" at most of clearance from the wall.

I'd love to do dual FV15HP's but even if I had the money down the road, I'd have a hard time spending $2500 on subs when i only spent $1200 on speakers and $1500 on a receiver. Of course I didn't think I'd buy my car after leasing it or buy a house either lol.

Sounds like 2 x XV15 or 1 FV15HP is the way to go, any reason the FV15HP is recommended more that the HSU VTF-15h? Also, this might be a strange question but are there any power/electrical issues I should be aware of as I'd have my AVR, TV, game systems, and subs all on the same circuit?


The Outlaw would be a great deal @ 600.00 shipped. Subwoofers is where most of your budget should be allocated towards...trust me. Dual FV15HP's would probably be the last subs you buy. The VTF-15 is not nearly as big of an upgrade from the Outlaw or PSA sub as the FV15HP. Thats why its not recomended much...still a great sub. I would start emailing these companies and get familiar with them. Warranty and Customer Service should be factored as well aside from comparing sheer output. SVS has some very attractive perks, with a 5yr warranty and 45 day free trial period. I really like the pc12nsd @ 699.00 shipped.
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post #21 of 142 Old 11-15-2013, 09:17 AM
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Definitely go with dual XV-15's. Nothing can beat them for the price.

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post #22 of 142 Old 11-15-2013, 09:21 AM - Thread Starter
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Since I'm a novice when it comes to audio, the 2 subs thing may just be me reading this forum too much haha. Maybe the better way to go is get the best 1 sub I can get and if absolutely needed get a 2nd one 4-5 years down the road when I have a more dedicated HT space. In my head I was thinking 2 would be the better way to go since I have a large room and 2 couches (one sub near each couch).
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post #23 of 142 Old 11-15-2013, 09:40 AM
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Originally Posted by basshead81 View Post

Ricci even said there is a difference...its not alot but there is. I know its tough for you to swallow as we have had this conversation multiple times but it is what it is. You say CEA2010 is not good enough but the HSU VTF-15 numbers match up well with data-bass...S&V numbers are close with Data-Bass on both the PC12 and XV15. My point with all that is you can see there is around a 1-1.5db difference with XV15.

Aside from all that I would go with a FV15HP anyhow.

CEA isn't good enough for the degree of accuracy you want to compare them at. You are quibbling over a decibel's difference in a measurement method when other factors such as a ten degree difference in temperature or a commensurately slight change in barometric pressure could make a greater difference. Besides you have ignored the matter of greater THD were the driver facing the mic. The numbers you present for the XV15 are inflated, and what's more they use averages to hide a peakish frequency response. The only way you can show that the XV15 is a higher performer than the LFM-1 EX is if you average out the CEA numbers and ignore compression and distortion measurements.
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post #24 of 142 Old 11-15-2013, 09:44 AM
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Originally Posted by Bill Fitzmaurice View Post

Having the port or cone facing away from the mic, or the listener, is moot, since the output of a port, and from the cone, within the sub woofer pass band is omni-directional. That's assuming that proper measuring protocol was followed, which means measuring from no less than 2 meters away, or if measured nearfield that the two results were properly combined. Where THD is concerned that will be lower if the mic is not facing the cone, as the above bandwidth harmonics that are components of the THD figure aren't omni-directional.

I agree, and I am actually making a point against the notion that the subwoofer's orientation makes a serious difference in subwoofer measurements. I don't believe it does, and to those who do you would have to factor in the distance not only from the woofer but also the port to be consistent in that view.
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post #25 of 142 Old 11-15-2013, 10:10 AM
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Originally Posted by basshead81 View Post

Another thing I would like to touch up on. I like how some you love to compare a variable tuning subs and only look at its max output mode for compression and THD. Look at the LFM-1 EX in 1 port mode. Ricci could not perform a 115db sweep, it has more compression @ 110db, and its THD is greater. When you look at the XV15 110db(NOT the 115db) sweep it maintains great composure and relatively low THD. Yes the XV15 has higher Second Order THD, but Ricci even states its the most benign of harmonics and preferred by some subjectively.

That's a fair point about compression on 1 port mode, although with respect to distortion they are about equal (if you ignore the XV15's higher THD at upper bass frequencies). However, if we bring the Outlaw back to two port mode, it manages to warrant a 113 dB distortion sweep which is not something the XV15 can achieve. As far as 'maintaining composure' at 110 dB, that is just not true. Past 105 dB, equalization can no longer rescue the driver, and the response turns peakish. The Outlaw driver does not need to crutch of equalization to hold linearity at any level, it is simply a higher bandwidth driver and retains a greater degree of accuracy at louder SPLs in either mode. PSA uses averaged CEA numbers for its products to disguise this fact.
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post #26 of 142 Old 11-15-2013, 10:40 AM
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Originally Posted by shadyJ View Post

That's a fair point about compression on 1 port mode, although with respect to distortion they are about equal.
There is a fundamental flaw in the sealing of ports to lower the tuning frequency, that being port chuffing. The lower tuning increases the airflow in the ports, while the reduced area results in more chuffing noise. The better way to reduce cab tuning is to add external extensions to the ports, the downside there being how that looks.
Another issue with lowering the tuning frequency is that also increases driver excursion within the primary power bandwidth. If some cabs measure with higher THD with porst sealed that would be the reason why.
In short, there are a few bad ways to have variable tuning, no good ways, so its value is dubious.

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post #27 of 142 Old 11-15-2013, 11:00 AM
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Originally Posted by shadyJ View Post

That's a fair point about compression on 1 port mode, although with respect to distortion they are about equal (if you ignore the XV15's higher THD at upper bass frequencies). However, if we bring the Outlaw back to two port mode, it manages to warrant a 113 dB distortion sweep which is not something the XV15 can achieve. As far as 'maintaining composure' at 110 dB, that is just not true. Past 105 dB, equalization can no longer rescue the driver, and the response turns peakish. The Outlaw driver does not need to crutch of equalization to hold linearity at any level, it is simply a higher bandwidth driver and retains a greater degree of accuracy at louder SPLs in either mode. PSA uses averaged CEA numbers for its products to disguise this fact.

The higher THD in the upper frequencies is still 2nd order. The XV15 has substantially less 3rd and 4th order harmonics comparing to 1 port @ 110db sweep the XV15 is very so slightly starting to compress below 25hz, the EX-1 exhibits this behavior even worse in 1 port mode and about slightly better in 2 port. The XV15 managed a 115db sweep. Also Ricci mentions the XV to offer reasonable output in room down to 12.5hz. I take it you only look at the graphs without referencing the notations below?
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post #28 of 142 Old 11-15-2013, 11:02 AM
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Originally Posted by shadyJ View Post

CEA isn't good enough for the degree of accuracy you want to compare them at. You are quibbling over a decibel's difference in a measurement method when other factors such as a ten degree difference in temperature or a commensurately slight change in barometric pressure could make a greater difference. Besides you have ignored the matter of greater THD were the driver facing the mic. The numbers you present for the XV15 are inflated, and what's more they use averages to hide a peakish frequency response. The only way you can show that the XV15 is a higher performer than the LFM-1 EX is if you average out the CEA numbers and ignore compression and distortion measurements.

I am not ignoring anything...I just feel no need to argue your moot points.
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post #29 of 142 Old 11-15-2013, 11:33 AM
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Originally Posted by Bill Fitzmaurice View Post

There is a fundamental flaw in the sealing of ports to lower the tuning frequency, that being port chuffing. The lower tuning increases the airflow in the ports, while the reduced area results in more chuffing noise. The better way to reduce cab tuning is to add external extensions to the ports, the downside there being how that looks.
Another issue with lowering the tuning frequency is that also increases driver excursion within the primary power bandwidth. If some cabs measure with higher THD with porst sealed that would be the reason why.
In short, there are a few bad ways to have variable tuning, no good ways, so its value is dubious.

As long as the subwoofer isn't driven hard enough to chuff, variable tuning can be an easy way to achieve a bit more extension. It's true that variable tuned subs tend to have worse performance as more ports are sealed, but again, as long as the subwoofer isn't driven as hard, there shouldn't be any audible difference with the exception of more deep bass output. If you were to argue that variable tuning isn't a completely optimal design to get the most out of a driver, I might agree, however I disagree when you say there are no good ways to have variable tuning. On the contrary, some of the best performing (for the price) commercial subs are variable tuned subs.
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post #30 of 142 Old 11-15-2013, 12:05 PM
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Originally Posted by eljaycanuck View Post

Based on the info on Data-Bass.com, I'd go with dual LFM-1 EXs, run them in one-port mode, and pocket the $400 difference.
I am going to differ here because I had both subs and the XV-15's are much cleaner as in no rattles or port noise. Better bass and two of the finest guys in the buisness to deal with. (Jim and Tom)
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