Honest Discussion: PSA XV15 vs HSU VTF-3 MK4 - Page 2 - AVS Forum | Home Theater Discussions And Reviews
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post #31 of 72 Old 04-13-2013, 09:26 AM
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Originally Posted by Saints View Post

So you are saying that Josh Ricci lied about port noise? Heh, I understand you are a PSA fanboy, but physics is physics. I had an Outlaw Plus and I often had port noise, the sub is a really nice sub, but it just couldn't do what I wanted it to do. In the end it cost me a bunch of money upgrading, but I have no regrets and still like the old Outlaw for a smaller room.

I do find it funny how obsessed people get with numbers on the subs though. For me it comes down to how much I have to spend at the time I want to buy a sub. If I had $800 I would get the PSA, if I had $1000 I would get the HSU, if I had $1500 I would get the Rythmik. All have proven to be great so just pick one, you won't be disappointed!

Very well said Saints, I find far to often because put way too much in the numbers of the subs. But that's just the nature of the business I guess. I can't say I completely agree with you on what subs I would buy in those price ranges but you're right about the numbers. The XV15 is a great sub whether it only has one port or not, hell it won Audioholics product of the year. And keep in mind that wasn't a "New product of the year" award either.
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post #32 of 72 Old 04-13-2013, 09:26 AM
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Originally Posted by matrixj3 View Post

Hmmm just like the HSU VTF 15H review....that i can understand. So they are low balling Psa and Hsu....now that makes PERFECT sense.

dont get me wrong i think HSU is a solid product! they were my next choice as they offered great customer service and were very helpful answering my questions!!

when I choose a company to purchase my subs from, these were my 3 credentials before pulling the trigger.

-Customer Service

-Price vs Performance

-Warranty

It just so happened PSA hit number 1 in all three categories from my research...HSU was slightly more expensive, customer service was great but not quite on par with Tom @PSA, and both have industry leading warranties. both SVS and Rythmik gave me the "my poop dont stink" impression when asking questions.
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post #33 of 72 Old 04-13-2013, 09:26 AM
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It is true, however, outiside a sub having a port and driver hitting the mic vs say just a driver(port is in the back) makes a difference. Inside you would get gain from both.

Based on the numbers I would say the PSA is the more powerful sub. I don't like multiple tuning either as I always want the deepest and loudest. When I had my SVS subs I always used the 16hz mode even though the 25hz was much louder.

BTW, I need to correct some posts here, 5-6 dBs is not twice as loud, 10 dBs is, whether bass or not. 3 dBs is twice as powerful, or needs twice the power. If one wants to increase only 3 dBs then they need twice the power. So say you are getting 105 dBs with your bass and it requires 250 watts, increasing 3 dBs or 108 dBs would need 500 watts! So 3 dBs is much more than one would think, especially when you get close to your amps limits. I can see playing at 80 dBs and raising it to 83 dBs may not seem like much but that is because you are still using little power.

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post #34 of 72 Old 04-13-2013, 09:33 AM
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Originally Posted by Saints View Post

So you are saying that Josh Ricci lied about port noise? Heh, I understand you are a PSA fanboy, but physics is physics. I had an Outlaw Plus and I often had port noise, the sub is a really nice sub, but it just couldn't do what I wanted it to do. In the end it cost me a bunch of money upgrading, but I have no regrets and still like the old Outlaw for a smaller room.

I do find it funny how obsessed people get with numbers on the subs though. For me it comes down to how much I have to spend at the time I want to buy a sub. If I had $800 I would get the PSA, if I had $1000 I would get the HSU, if I had $1500 I would get the Rythmik. All have proven to be great so just pick one, you won't be disappointed!

why dont you go get a psa xv15 and find and see for yourself(not being rude). but please dont come in this thread trying to call me a fanboy. i have owned these subs less than a week, im still trying to find flaws. I had my brother and another friend listen to see if my ears were bad. again I ran some bass cd's on these subs at reference levels and any possible port noise was in audible. now thats 3 people saying the same thing. You can call me fan boy, liar or whatever, however I am just trying to give a honest opinion. I even emailed Tom and asked about the port noise that was reported on audioholics website because I have yet to experience. Refer to his post for a better explanation on it.
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post #35 of 72 Old 04-13-2013, 09:39 AM
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Originally Posted by MKtheater View Post

It is true, however, outiside a sub having a port and driver hitting the mic vs say just a driver(port is in the back) makes a difference. Inside you would get gain from both.

Based on the numbers I would say the PSA is the more powerful sub. I don't like multiple tuning either as I always want the deepest and loudest. When I had my SVS subs I always used the 16hz mode even though the 25hz was much louder.

BTW, I need to correct some posts here, 5-6 dBs is not twice as loud, 10 dBs is, whether bass or not. 3 dBs is twice as powerful, or needs twice the power. If one wants to increase only 3 dBs then they need twice the power. So say you are getting 105 dBs with your bass and it requires 250 watts, increasing 3 dBs or 108 dBs would need 500 watts! So 3 dBs is much more than one would think, especially when you get close to your amps limits. I can see playing at 80 dBs and raising it to 83 dBs may not seem like much but that is because you are still using little power.

yes i agree, i posted that incorrectly...thanks for the correction!
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post #36 of 72 Old 04-13-2013, 09:42 AM
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Originally Posted by jbrown15 View Post

If this is true why does Josh even bother facing all of the subs at the mic when taking the measurements? My not just turn them 90degrees to the mic and have them fire away from it?


It's not true.

When you flip a down firing sub on its side outside at 2m you are moving the acoustic center of the cone MUCH closer to the mic.

Per CEA the mic will be 2 meters from the subwoofer(not the cone). So a down firing driver's (cone)center will likely be 2 meters + say ten inches or so in the case of our XV15. Flip the sub on its side and you move the center of the cone 10" closer to the mic. Anyone who has spent a little time measuring speakers/subwoofers knows this will increase the recorded levels.

the CEA-2010 directive doesn't delve into all of the possible subwoofer designs or how to orient them during testing. Josh has spent a great deal of time on just two of the variations(dual opposed and triple opposed) with interesting results(found on his website).

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post #37 of 72 Old 04-13-2013, 09:52 AM
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Originally Posted by matrixj3 View Post

Hmmm just like the HSU VTF 15H review....that i can understand. So they are low balling Psa and Hsu....now that makes PERFECT sense.

I'm not sure what is sarcasm or not but just to "nip it in the bud" so to speak----we(Jim or myself) in NO WAY feel that Audioholics was "low balling" our product. On the contrary, we feel that Josh Ricci(reviewer for Audioholics) is one of the most knowledgeable professionals in the field.

Also, I'm not sure if its public knowledge but if any manufacturer doesn't feel test data is accurate they can contact Audioholics for a retest at no charge what-so-ever(or, if the retest is desired well after the review is published.....a *very* reasonable fee).

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post #38 of 72 Old 04-13-2013, 09:53 AM
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Originally Posted by Tom Vodhanel View Post

It's not true.

When you flip a down firing sub on its side outside at 2m you are moving the acoustic center of the cone MUCH closer to the mic.

Per CEA the mic will be 2 meters from the subwoofer(not the cone). So a down firing driver's (cone)center will likely be 2 meters + say ten inches or so in the case of our XV15. Flip the sub on its side and you move the center of the cone 10" closer to the mic. Anyone who has spent a little time measuring speakers/subwoofers knows this will increase the recorded levels.

the CEA-2010 directive doesn't delve into all of the possible subwoofer designs or how to orient them during testing. Josh has spent a great deal of time on just two of the variations(dual opposed and triple opposed) with interesting results(found on his website).

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Tom, I was not insisting Josh is a liar, My apologies if my post about the port chuffing was "made up" being offensive. I made a assumption based on our emails back and forth. I dont recall that you mentioned anything about there actually being port noise during a certain film track, I thought you said the "port noise" was basically put in the review because of the lack of cons when testing the xv15. Oh btw I sent ya a email!
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post #39 of 72 Old 04-13-2013, 09:57 AM
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I would just stick to Josh's advice and add another 1-1.5db to the output. It seems to me like the XV-15 has the edge, but that sale on the Outlaw is nothing to be sneezed at. For that price difference you can get a nice USB mic and REW and measure your own room to tweak and still have almost $100 in your pocket.
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post #40 of 72 Old 04-13-2013, 10:00 AM
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I think Josh does excellent work and wish there was a lot more subs tested by him. I personally would love to see some detailed measurements for a lot more from Rythmik, PSA, Funk Audio, JTR and Seaton products. What he does is a great service to the general public that takes these measurements into consideration when buying a sub. Thanks again Josh!
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post #41 of 72 Old 04-13-2013, 10:20 AM
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Yes, Josh's tests are the best! His website is awesome as well. The PSA sub chuffing during Pulse is not a big deal, it has made subs cry uncle. It is a high level 15-19hz scene that lasts a long time. Ported subs tuned in that region will have troubles. Try that scene and I bet you will hear some noises at reference! Now, add enough subs and problem solved.

OP, the PSA will have a slight advantage in spl without changing any tunes. Very convenient however it costs a little more. Both subs would be great I am sure. If you think you will be running the sub loud then Every spl matters to keep sounding good. If you listen a bit lower than save some money.

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post #42 of 72 Old 04-13-2013, 10:47 AM
 
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Originally Posted by Tom Vodhanel View Post

The increase in output is from the entire cone area being closer to the measurement microphone.
I didn't go back and look at the testing protocol, I just assumed that it was done correctly. Not that one has to take measurements at 10m like Tom Danley does, but if the mic is close enough that rotating the cab would make a significant difference, it's too close.
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If this is true why does Josh even bother facing all of the subs at the mic when taking the measurements? Why not just turn them 90degrees to the mic and have them fire away from it?
I don't know how Josh does his measurements. I do mine at 4 meters. At that distance the polar response would be a very uniform 360 degrees with no more than 1/2 dB variation. There would be a difference in the response based on the aiming of the cab above where radiation pattern is omni-directional, but that would not occur within the subwoofer pass band unless said sub had a baffle dimension in excess of roughly 3 feet.
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post #43 of 72 Old 04-13-2013, 11:06 AM - Thread Starter
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Thanks everyone for chiming in. This thread will help lots of users in my situation. And thanks to Tom for dropping in and sharing some insightful information. This really adds greatly to the info on this thread.

Btw, I am also one of those that have received stellar pre-sales support from Tom.

Just to keep the situation updated and on point to my post, we are discussing:

As of today, April 13,2013.

PSA XV15 - $799 (shipped excluding taxes where applicable)
Vs
HSU VTF-3 MK4 - &768 (shipped excluding taxes where applicable)
Vs
Outlaw EX-1 - $629 (shipped excluding taxes where applicable)

I think what I am seeing here as far as product performance goes is that a ported 15 inch sub (XV15) can indeed be good for music and can deliver low and loud for movies as well. Yes, you can get lower and louder but will need to add at least a few hundred dollars to get there. Sound accurate?

Also, thanks to MKTheater for confirming my point that 10dB is twice as loud. I was dead sure that was right:)
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post #44 of 72 Old 04-13-2013, 11:12 AM
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Originally Posted by bowmah View Post

Thanks everyone for chiming in. This thread will help lots of users in my situation. And thanks to Tom for dropping in and sharing some insightful information. This really adds greatly to the info on this thread.

Btw, I am also one of those that have received stellar pre-sales support from Tom.

Just to keep the situation updated and on point to my post, we are discussing:

As of today, April 13,2013.

PSA XV15 - $799 (shipped excluding taxes where applicable)
Vs
HSU VTF-3 MK4 - &768 (shipped excluding taxes where applicable)
Vs
Outlaw EX-1 - $629 (shipped excluding taxes where applicable)

I think what I am seeing here as far as product performance goes is that a ported 15 inch sub (XV15) can indeed be good for music and can deliver low and loud for movies as well. Yes, you can get lower and louder but will need to add at least a few hundred dollars to get there. Sound accurate?

Also, thanks to MKTheater for confirming my point that 10dB is twice as loud. I was dead sure that was right:)
yes you were right bowmah my apologies. I was thinking 3db takes twice the power and had it mixed up with being twice as loud. however the actual point to my post was 3db is far from insignificant. again aside from the measurements imo no 12 will do what a 15 will with similar power and enclosure design, its just simple physics.
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post #45 of 72 Old 04-13-2013, 11:14 AM
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Originally Posted by jbrown15 View Post

Has anyone heard of the new PASCAL converted numbers that CEA now mandates?

Bill, I know you are a very knowledgeable resource. Would you care to weigh in on this?
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post #46 of 72 Old 04-13-2013, 11:32 AM - Thread Starter
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Originally Posted by basshead81 View Post

again aside from the measurements imo no 12 will do what a 15 will with similar power and enclosure design, its just simple physics.

Hey no worries. You know, I think this thread is just a good reminder of this. Thanks for all your thoughts too and I agree, 3dB can be significant in HT.
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post #47 of 72 Old 04-13-2013, 11:45 AM
 
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Originally Posted by jbrown15 View Post

Bill, I know you are a very knowledgeable resource. Would you care to weigh in on this?
I'm not aware of any controversy regarding Pascal units.
As for the CEA procedure in general, there's nothing earthshaking there. The main points it makes is measuring from no less than two meters, and using distortion to qualify maximum SPL. In the pro-sound world we've been doing that for years. As I mentioned, Tom Danley measures his subs at 10m with 100w input, so it gives a far better real world result than even CEA as far as sensitivity is concerned. After all, who listens to a sub at one watt? Where distortion enters the picture, that gives a real world maximum SPL result, which is far more accurate than calculated maximum SPL figures, which ignore such things as thermal and mechanical power compression, and that all important driver spec, xmax.
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post #48 of 72 Old 04-13-2013, 11:53 AM
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Originally Posted by basshead81 View Post

Tom, I was not insisting Josh is a liar, My apologies if my post about the port chuffing was "made up" being offensive. I made a assumption based on our emails back and forth. I dont recall that you mentioned anything about there actually being port noise during a certain film track, I thought you said the "port noise" was basically put in the review because of the lack of cons when testing the xv15. Oh btw I sent ya a email!


No,no...not at all basshead. I've just seen innocent comments taken *completely* out of context so many times over the years I wanted to try to clarify things now. The "vibe" I got when speaking with Audioholics/Josh was that the port noise "con" was listed simply because they couldn't think of much else to list. As I mentioned, I understand how it could be a concern for potential buyers and I'd suggest everyone look over the threads(which have PLENTY of XV15 owners posting) and decide for themselves if this is going to be a problem. There's a lot of good options to consider in the $800 range.

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post #49 of 72 Old 04-13-2013, 11:59 AM
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Quote:
Originally Posted by bowmah View Post

Thanks everyone for chiming in. This thread will help lots of users in my situation. And thanks to Tom for dropping in and sharing some insightful information. This really adds greatly to the info on this thread.

Btw, I am also one of those that have received stellar pre-sales support from Tom.

Just to keep the situation updated and on point to my post, we are discussing:

As of today, April 13,2013.

PSA XV15 - $799 (shipped excluding taxes where applicable)
Vs
HSU VTF-3 MK4 - &768 (shipped excluding taxes where applicable)
Vs
Outlaw EX-1 - $629 (shipped excluding taxes where applicable)

I think what I am seeing here as far as product performance goes is that a ported 15 inch sub (XV15) can indeed be good for music and can deliver low and loud for movies as well. Yes, you can get lower and louder but will need to add at least a few hundred dollars to get there. Sound accurate?

Also, thanks to MKTheater for confirming my point that 10dB is twice as loud. I was dead sure that was right:)

I think you are spot on. Unless you go DIY, you will need to step up to the $1000-1500 shipped range (Hsu VTF-15H, PSA XS30/XV30, Rythmik 15HP, etc).

If you are open to DIY you can easily beat anything listed here.
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post #50 of 72 Old 04-13-2013, 12:06 PM
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Quote:
Originally Posted by Bill Fitzmaurice View Post

I'm not aware of any controversy regarding Pascal units.
As for the CEA procedure in general, there's nothing earthshaking there. The main points it makes is measuring from no less than two meters, and using distortion to qualify maximum SPL. In the pro-sound world we've been doing that for years. As I mentioned, Tom Danley measures his subs at 10m with 100w input, so it gives a far better real world result than even CEA as far as sensitivity is concerned. After all, who listens to a sub at one watt? Where distortion enters the picture, that gives a real world maximum SPL result, which is far more accurate than calculated maximum SPL figures, which ignore such things as thermal and mechanical power compression, and that all important driver spec, xmax.

So is that method better? why isn't that method of measuring used more then?
Please don't think I have any alternative motives with my questions, there are strictly for me trying to learn more.

How would measuring a sub that's 10m's away from the mic give you a more real world result? Most subs in peoples rooms would probably be less then 3m's away from their listening position.

Thanks
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post #51 of 72 Old 04-13-2013, 12:06 PM
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Originally Posted by Bill Fitzmaurice View Post

I didn't go back and look at the testing protocol, I just assumed that it was done correctly. Not that one has to take measurements at 10m like Tom Danley does, but if the mic is close enough that rotating the cab would make a significant difference, it's too close.
I don't know how Josh does his measurements. I do mine at 4 meters. At that distance the polar response would be a very uniform 360 degrees with no more than 1/2 dB variation. There would be a difference in the response based on the aiming of the cab above where radiation pattern is omni-directional, but that would not occur within the subwoofer pass band unless said sub had a baffle dimension in excess of roughly 3 feet.


You can purchase the CEA directives for a very reasonable price. Or, just google them and I'm sure you'll find the basics. Might be a good idea to know what the testing protocol *is* before questioning the qualifications of those who are following them? 2m is the industry standard for subwoofer GP work,. If you want to learn why I suggest starting with Don Keele's works. He was largely responsible for the CEA procedures.


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post #52 of 72 Old 04-13-2013, 12:15 PM
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Quote:
Originally Posted by Bill Fitzmaurice View Post

I'm not aware of any controversy regarding Pascal units.
As for the CEA procedure in general, there's nothing earthshaking there. The main points it makes is measuring from no less than two meters, and using distortion to qualify maximum SPL. In the pro-sound world we've been doing that for years. As I mentioned, Tom Danley measures his subs at 10m with 100w input, so it gives a far better real world result than even CEA as far as sensitivity is concerned. After all, who listens to a sub at one watt? Where distortion enters the picture, that gives a real world maximum SPL result, which is far more accurate than calculated maximum SPL figures, which ignore such things as thermal and mechanical power compression, and that all important driver spec, xmax.


Why on earth would you think that CEA testing somehow limits the DUT(device under test) to 1 watt? The CEA-2010 testing has the device producing maximum output capabilities within a distortion limited context. In every commercial example I known of(measuring myself, or seeing the data recorded) the amplification of the subwoofer was pushed to its absolute limits at some point in the testing. The linear throw of the driver is also a key component in the performance recorded with CEA-2010. With regards to thermal or mechanical power compression Josh Ricci actually does additional tests in that regard.(above and beyond the CEA directives).

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post #53 of 72 Old 04-13-2013, 12:40 PM
 
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Originally Posted by MKtheater View Post

It is true, however, outiside a sub having a port and driver hitting the mic vs say just a driver(port is in the back) makes a difference. Inside you would get gain from both.

Based on the numbers I would say the PSA is the more powerful sub. I don't like multiple tuning either as I always want the deepest and loudest. When I had my SVS subs I always used the 16hz mode even though the 25hz was much louder.

BTW, I need to correct some posts here, 5-6 dBs is not twice as loud, 10 dBs is, whether bass or not. 3 dBs is twice as powerful, or needs twice the power. If one wants to increase only 3 dBs then they need twice the power. So say you are getting 105 dBs with your bass and it requires 250 watts, increasing 3 dBs or 108 dBs would need 500 watts! So 3 dBs is much more than one would think, especially when you get close to your amps limits. I can see playing at 80 dBs and raising it to 83 dBs may not seem like much but that is because you are still using little power.

10 dB is subjectively twice as loud, which is only true for some people. If I turn my systems up by 10 dB, personally I would say it is more than merely doubled in loudness. A 3 dB difference could arguably be called a twice as loud too, at least physically, if not perceptually. 6 dB is a doubling of sound pressure level, and what most people normally call 'sound'. Anyway, here is a page to explain the differences.
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post #54 of 72 Old 04-13-2013, 01:10 PM
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Originally Posted by ack_bk View Post

I would just stick to Josh's advice and add another 1-1.5db to the output. It seems to me like the XV-15 has the edge, but that sale on the Outlaw is nothing to be sneezed at. For that price difference you can get a nice USB mic and REW and measure your own room to tweak and still have almost $100 in your pocket.
+ 1 on the on sale EX Outlaw and mic/REW combo.
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post #55 of 72 Old 04-13-2013, 01:36 PM
 
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Originally Posted by jbrown15 View Post

So is that method better? why isn't that method of measuring used more then?
It used to be that to obtain a standard 1w/1w result you might stick a mic 1m from the speaker and measure with one watt. The problem is that when you put the mic 1m from the speaker you don't get an accurate result, for a variety of reasons. Not everyone actually did it that way, they usually measured from a longer distance and extrapolated the result to a 1m/1w result, but as there was no real standard many would measure at 1m and get spurious results.
But the main advantage to CEA is with respect to maximum output, which actually measures how loud the sub will go before exceeding 10% THD, making it a useful and accurate figure. The previous 'calculated maximum SPL' method added the linear dB increase associated with the speakers maximum thermal power rating to the base sensitivity. The problem there is that the increase in dB output isn't linear with respect to power applied, and that a driver could well run out of excursion capability long before the thermal rating was reached. Actual measured maximum SPL could be as much as 6dB lower than the calculated figure.
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How would measuring a sub that's 10m's away from the mic give you a more real world result?
It takes the cabinet out of the equation. At close distances the cabinet influences the result. You have to get well away from it for it to behave as a point source.
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post #56 of 72 Old 04-13-2013, 01:51 PM
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Originally Posted by Bill Fitzmaurice View Post

It takes the cabinet out of the equation. At close distances the cabinet influences the result. You have to get well away from it for it to behave as a point source.

Sorry it takes the cabinet of the sub out of the equation? why would you want to do that? isn't the enclosure part of the reason the sub performs the way it does and effects the overall performance and measurements numbers?
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post #57 of 72 Old 04-13-2013, 02:05 PM
 
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Originally Posted by jbrown15 View Post

Isn't the enclosure part of the reason the sub performs the way it does and effects the overall performance and measurements numbers?
It is, but the issue here is that how the enclosure affects performance changes with the distance at which it's measured. If one wanted to really fool with the results they'd measure from six inches away. Danley takes the extreme opposite approach; by measuring at 10 meters no one can impeach his results. He used to measure at 20 meters, he mentions that in a post on the matter dated 1998. I guess the parking lot at Danley Labs isn't big enough to allow that any more. I measure at 4 meters because I have neighbors, and it would bother them if I measured from further away at a level sufficient to eliminate any environmental contamination of the result. Tom and I both believe that when you measure you want to give as honest a result as possible, and that means being conservative. I'd rather my results come in 2dB less than the average user will get than 2dB more. No one ever complains about getting more than they expected.
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post #58 of 72 Old 04-13-2013, 04:23 PM
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Originally Posted by Bill Fitzmaurice View Post

It is, but the issue here is that how the enclosure affects performance changes with the distance at which it's measured. If one wanted to really fool with the results they'd measure from six inches away. Danley takes the extreme opposite approach; by measuring at 10 meters no one can impeach his results. He used to measure at 20 meters, he mentions that in a post on the matter dated 1998. I guess the parking lot at Danley Labs isn't big enough to allow that any more. I measure at 4 meters because I have neighbors, and it would bother them if I measured from further away at a level sufficient to eliminate any environmental contamination of the result. Tom and I both believe that when you measure you want to give as honest a result as possible, and that means being conservative. I'd rather my results come in 2dB less than the average user will get than 2dB more. No one ever complains about getting more than they expected.

This doesn't really make sense too me, why would you only try to measure the driver and take the cabinet out of the equation? I understand different quality drivers can have significant performance advantages but the cabinet is half of the equation of the performance of the total package. Seems strange too me, but like I said I'm still learning. If this is a better way to measure the true performance of a sub why hasn't it been adopted as the standard to measure and gauge the performance of subs?
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post #59 of 72 Old 04-13-2013, 04:31 PM
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Originally Posted by basshead81 View Post

just curious have you ever compared 3db going off of a spl meter?


Yes I have. The subs were are talking about all have enough umph to achieve similar spl in a room with great results. IMHO not a deciding factor.
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post #60 of 72 Old 04-13-2013, 04:36 PM
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It only matters if you are pushing the subs hard enough where one might compress but the other will have 2 dBs headroom and not compress and preserve dynamics. So it depends on how hard you push it, again it is like the difference of 200 watts or 400 watts, so I matters but only if you approach those limits.

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