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post #61 of 149 Old 01-26-2014, 06:34 PM
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Quote:
Originally Posted by shadyJ View Post

Its true the VTF15h would have to work harder to keep up, but I don't think the XS30 would have fully twice the output across the board above 30 Hz. Probably from 45 to 55 Hz, I think it would, but not as much outside of that. Remember that sealed designs lose a little bit of efficiency even above the port's band. Also keep in mind the drivers in an XS30 do not have as much power as the XV15 does. We can't know for sure unless data-bass measures one, and I doubt that will ever happen. PSA can not be taken at their word for their sub's performance, they have already proven themselves to be unreliable.

The only one claiming that PSA is putting out false info on their subs is you really, Josh Ricci himself noted that the XV15 posted extremely close to the output numbers that PSA was claiming. I believe he even said that it was one of the closest subs he's tested to coming to the claimed manufactures numbers.

PSA claims that from 40-63hz a single XS30 can hit 122dB 2m ground plane. I see no reason to not believe them, especially with what Josh has said about PSA subs. In my room I have had a single XS30 hit 117dB from my LP and still not even pushing the sub hard.

LOL... how are they unreliable? I don't think Tom would have any issues getting Josh to test a XS30 if Josh wasn't as extremely busy as he is.
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post #62 of 149 Old 01-26-2014, 06:45 PM
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What's so funny Shady is that you say we can't trust PSA's numbers on any of their products and act like HSU is upfront about everything. Yet if you look at the data-bass numbers on the VTF15-H and compare them directly to the posted numbers from the HSU webpage and subtract 6dB from them because the HSU numbers are 1m ground plane numbers; The claims from HSU aren't even close to the actual measured numbers from Josh. HSU's numbers are 3dB higher then what Josh measured, yet some how PSA is the only company lying about their measurements according too you....LOL rolleyes.gif
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post #63 of 149 Old 01-26-2014, 06:50 PM
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This is directly from HSU's webpage.

VTF-15H CEA 2010 One Port Open Test Result:

Tone Burst Center Frequency (Hz) Maximum SPL CEA 2010 Rating
16 109.3
20 113.4 115.0
25 115.0
31.5 119.2
40 122.3 122.6
50 122.7
63 122.9
80 123.0

VTF-15H CEA 2010 Two Ports Open Test Result:

Tone Burst Center Frequency (Hz) Maximum SPL CEA 2010 Rating
16 106.9
20 113.7 118.2
25 118.9
31.5 121.9
40 124.5 124.2
50 124.4
63 123.8
80 123.8

Take off 6dB from those numbers because its all done at 1m ground plane and then tell me how those are accurate compared to Josh's numbers

1 port mode


2 port mode
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post #64 of 149 Old 01-26-2014, 06:54 PM
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Quote:
Originally Posted by jbrown15 View Post

Josh Ricci himself noted that the XV15 posted extremely close to the output numbers that PSA was claiming. I believe he even said that it was one of the closest subs he's tested to coming to the claimed manufactures numbers.

LOL... how are they unreliable? I don't think Tom would have any issues getting Josh to test a XS30 if Josh wasn't as extremely busy as he is.

Josh Ricci noted that the XV15 tests were close to PSA's own claims.. but then after that, PSA decided to add output on top of Ricci's measurements. That is why those numbers are false. As for unreliability, you have PSA playing with numbers like that, and also look at the differences in compression tests that I just pointed out a few posts above. What PSA claims and what third party data reveals are not the same thing. PSA can not be trusted. And they could easily arrange to have Josh measure their subs if they wanted. Go to Josh's forum and ask him what it takes for him to measure a subwoofer, it is not free and won't happen right away, but it can be done without much of a hassle from what I understand. No way PSA will have their sealed subs tested, their driver's weaknesses will be even more exposed than on their ported model.
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post #65 of 149 Old 01-26-2014, 06:59 PM
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Anyways..... we get it you don't trust PSA, big surprise.

Maybe you care to explain why HSU's are so trust worthy compared to Josh's....lol
Which we wouldn't even have to go by if a few us hadn't thrown some cash together to ship one to Josh to test out.
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post #66 of 149 Old 01-26-2014, 07:24 PM
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What you have missed is Josh uses RMS testing, but CEA protocol is burst testing, and to go from Burst to RMS, you have to subtract a further 3 dB. Hsu posted their measurements in stricter adherence to CEA protocol, but that isn't to say what Josh does is not as valid, you just have to subtract 9 dB to get an equal to Josh's numbers. With that in mind Hsu's number are extremely close to Ricci's measurements, in fact Josh's tend to be slightly higher than Hsu's own measurements. Here are Hsu's number adjusted for 9 dB:

One port mode:
16: 100.3
20: 104.4
25: 106
31: 110.2
40: 113.3
50: 113.7
63: 113.9
80: 114

Two port mode:
16: 97.9
20: 104.7
25: 109.9
31: 112.9
40: 115.5
50: 115.4
63: 114.8
80: 114.8


If that is the case, you might ask why Hsu doesn't just use data-bass's number on the VTF15h's product page? Because then the internal benchmarks by which you can judge Hsu's own products against each other is ruined. CEA testing is good only for a rough output comparison between different data sets, not a precise one.

This is partly what makes PSA's own comparison charts bogus, they are using numbers gathered by other testers to a degree that CEA isn't suited for. Plus they can run a whole bunch of different CEA tests on their own subs and just pick the ones that are the best, and throw out the variations which would give their sub's measurements a huge and unfair advantage. There is no integrity in the way they are promoting their subs. PSA's CEA data gathered in-house could be looked on as valid only against their own data set.
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post #67 of 149 Old 01-27-2014, 08:25 AM
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Quote:
Originally Posted by shadyJ View Post

Quote:
Originally Posted by jbrown15 View Post

Josh Ricci himself noted that the XV15 posted extremely close to the output numbers that PSA was claiming. I believe he even said that it was one of the closest subs he's tested to coming to the claimed manufactures numbers.

LOL... how are they unreliable? I don't think Tom would have any issues getting Josh to test a XS30 if Josh wasn't as extremely busy as he is.

Josh Ricci noted that the XV15 tests were close to PSA's own claims.. but then after that, PSA decided to add output on top of Ricci's measurements. That is why those numbers are false. As for unreliability, you have PSA playing with numbers like that, and also look at the differences in compression tests that I just pointed out a few posts above. What PSA claims and what third party data reveals are not the same thing. PSA can not be trusted. And they could easily arrange to have Josh measure their subs if they wanted. Go to Josh's forum and ask him what it takes for him to measure a subwoofer, it is not free and won't happen right away, but it can be done without much of a hassle from what I understand. No way PSA will have their sealed subs tested, their driver's weaknesses will be even more exposed than on their ported model.
If I'm reading this right, you're saying that after Ricci tested the sub and noted the agreement in measurements he performed with those that PSA claimed, PSA then added or somehow changed the numbers. Can you provide some examples of this? You've mentioned the term 'extrapolation' before. Extrapolation is not inherently a bad thing providing that the model is well understood. That's not to say the results are guaranteed because the further out you forecast, the more uncertainty there is with numbers taking on a decidedly fuzzy nature. In this particular case, just what is it that makes the red flag in any extrapolation that PSA has performed so ominous?

Nice explanation on the differences between HSU and Ricci's methodologies and results.

"I've found that when you want to know the truth about someone that someone is probably the last person you should ask." - Gregory House
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post #68 of 149 Old 01-27-2014, 09:21 AM
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Originally Posted by Chu Gai View Post

If I'm reading this right, you're saying that after Ricci tested the sub and noted the agreement in measurements he performed with those that PSA claimed, PSA then added or somehow changed the numbers. Can you provide some examples of this? You've mentioned the term 'extrapolation' before. Extrapolation is not inherently a bad thing providing that the model is well understood. That's not to say the results are guaranteed because the further out you forecast, the more uncertainty there is with numbers taking on a decidedly fuzzy nature. In this particular case, just what is it that makes the red flag in any extrapolation that PSA has performed so ominous?

Nice explanation on the differences between HSU and Ricci's methodologies and results.

When downfiring subs are tested, sometimes their measured output can be affected by the driver and microphone not being in a direct line of sight. You can normally expect the difference to be .5 -1.5 db.

I don't see a problem with this, but I can see Shady's point too. I believe Shady's problem is that PSA turned "probably is" into "is", stirred it into the "formula", and published the chart.

What's almost tragic in this forever long battle, is that I believe even Shady's most ardent opposition wouldn't mind seeing that chart go away.
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post #69 of 149 Old 01-27-2014, 09:52 AM
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Originally Posted by shadyJ View Post


Josh Ricci noted that the XV15 tests were close to PSA's own claims.. but then after that, PSA decided to add output on top of Ricci's measurements. That is why those numbers are false.

 

Personally, before I would make a baseless accusation and call PSA liars, I would make sure I had a solid understanding of CEA2010 test procedures.  Josh Ricci himself stated that rotating the cab, as they did for example with the outlaw lfm1-ex, so that the woofer faces the mic, unlike its natural downfiring position, levels the playing field to make for accurate comparisons of tested subs.  Without facing the mic, output will be reduced about 1.5 dB.  And no, I already know that your rebuttal is that you think this will also raise distortion, and this is also false.  Josh Ricci states that rotating the woofer to face the mic adds about 1.5 dB of CEA2010 output, which means with distortion below the allowable threshold.  So making up some idea that output wont be higher is just uninformed bunk.

 

Josh Ricci:

 

"The Data-Bass CEA-2010 results were within about a dB of PSA's own internal results and the other measurements corroborated each other well."

 

Josh is comparing his test numbers to PSA's numbers and says the above.  You say that PSA's numbers are false.  So Josh's numbers are false also?  You are not making any sense at all.  Either the numbers match or they don't. You can't just make stuff up like you CLAIM PSA is doing.  This is one of the big issues everyone has with the lies you spew.  You make these claims, but the facts don't match up to the claims you are making up.  How do you answer that?  Do the numbers match or not? Answer the question.  I have one other question for you.  What is the best home theater ID 15" sub for under $800 shipped?.............?

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post #70 of 149 Old 01-27-2014, 09:56 AM
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Originally Posted by Tack View Post


When downfiring subs are tested, sometimes their measured output can be affected by the driver and microphone not being in a direct line of sight. You can normally expect the difference to be .5 -1.5 db.

I don't see a problem with this, but I can see Shady's point too. I believe Shady's problem is that PSA turned "probably is" into "is", stirred it into the "formula", and published the chart.

What's almost tragic in this forever long battle, is that I believe even Shady's most ardent opposition wouldn't mind seeing that chart go away.


What is also involved in this is the fact that, when placing the mic 2m from the cab, you are 2m + almost another foot from the center of the woofer.  Obviously, distance from the woofer has a dramatic impact on the SPL, as evidence by the 9dB difference between 2m and 1m testing.

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post #71 of 149 Old 01-27-2014, 10:06 AM
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What is also involved in this is the fact that, when placing the mic 2m from the cab, you are 2m + almost another foot from the center of the woofer.  Obviously, distance from the woofer has a dramatic impact on the SPL, as evidence by the 9dB difference between 2m and 1m testing.

I could have sworn Josh's "two meters" was measured from the centerline of the driver. I don't know for sure though.

Illka and Slartibartfast used to flip the downfiring subs on their side when he tested them. But then we wouldn't get pages and pages of arguments. AVS page views would suffer. smile.gif
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post #72 of 149 Old 01-27-2014, 10:10 AM
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From databass "and the microphone is placed pointing at the subwoofer at a distance of 2 meters from the nearest enclosure edge or face".

So apparently not.
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post #73 of 149 Old 01-27-2014, 10:27 AM
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I don't quite understand the staunch opposition going on. Can we see your ID Police badge? Did an XS30 tip over onto the family pet and you must have revenge? If PSA makes a crappy product that no one wants, they won't last. If people are happy with their stuff, they will succeed. It's all quite simple. Maybe all the researching and bashing is just a hobby? It seems to be consuming a lot of your time. Perhaps take up knitting or watercolors. The world will survive without your PSA fixation. FWIW, I don't own a PSA sub, and don't plan on buying one any time soon. I have no skin in the game. But your regular interjections about PSA into any thread in which they're mentioned is sort of annoying.
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post #74 of 149 Old 01-27-2014, 10:27 AM
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Quote:
Originally Posted by Tack View Post

When downfiring subs are tested, sometimes their measured output can be affected by the driver and microphone not being in a direct line of sight. You can normally expect the difference to be .5 -1.5 db.

I don't see a problem with this, but I can see Shady's point too. I believe Shady's problem is that PSA turned "probably is" into "is", stirred it into the "formula", and published the chart.

What's almost tragic in this forever long battle, is that I believe even Shady's most ardent opposition wouldn't mind seeing that chart go away.


There is no "probably" in this context. When the measurement mic is moved further from the driver....you lose pressure(volume). In this case we have about a 12-13" difference. Or, going from what would have been about 78-79 inches to about 90-91 inches. That is a 15% increase. This means a 1.2(ish) drops in pressure/volume.

Josh Ricci has stated this is correct.

There is one person who pretends he doesn't understand any of this. This way he has an excuse to continually hurl personal attacks at me and attacks at Power Sound Audio in general.

If you take into account this distance discrepancy our website measurements are within a FRACTION of a dB of Josh Ricci *AND* Brent Butterworth. But still, our data is deemed "unreliable" by some who's agenda should be obvious to just about everyone by now.

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post #75 of 149 Old 01-27-2014, 10:27 AM
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What's almost tragic in this forever long battle, is that I believe even Shady's most ardent opposition wouldn't mind seeing that chart go away.

 

I agree with this whole sentence. And I really agree with you on the part that it's a forever long battle. It's funny, if you look back over the last few months you will see multiple threads just like this one. We should just make a sticky thread titled "Pros and Cons of the PSA Chart". That way this argument could be contained and quarantined in a single location. Kind of like the Leper Colonies of old.  

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post #76 of 149 Old 01-27-2014, 10:36 AM
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What is also involved in this is the fact that, when placing the mic 2m from the cab, you are 2m + almost another foot from the center of the woofer.  Obviously, distance from the woofer has a dramatic impact on the SPL, as evidence by the 9dB difference between 2m and 1m testing.


Exactly. You are going from about 79 inches to about 91 inches. That is a 15% increase and will change volume about 1.21dB. I added 1.0dB not the full 1.21dB to our numbers.

ALSO----per 2010 CEA guidelines we convert all output to pascal, average, then back to decibel. If you are NOT doing this conversion, you will *not* get the same data as we post for ANY product. This doesn't make us "liars" or "unreliable"....it simple means you are not PROPERLY (per CEA-2010 guidelines) averaging the data.

Follow the guide lines for 2010-CEA and scale the data to a true 2m(79 inches) and you will get exactly what the XV15 chart indicates. Well, technically you will get about 0.21dB MORE for the XV15..smile.gif


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post #77 of 149 Old 01-27-2014, 10:37 AM
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Quote:
Originally Posted by Tom Vodhanel View Post

There is no "probably" in this context. When the measurement mic is moved further from the driver....you lose pressure(volume). In this case we have about a 12-13" difference. Or, going from what would have been about 78-79 inches to about 90-91 inches. That is a 15% increase. This means a 1.2(ish) drops in pressure/volume.

Josh Ricci has stated this is correct.

There is one person who pretends he doesn't understand any of this. This way he has an excuse to continually hurl personal attacks at me and attacks at Power Sound Audio in general.

If you take into account this distance discrepancy our website measurements are within a FRACTION of a dB of Josh Ricci *AND* Brent Butterworth. But still, our data is deemed "unreliable" by some who's agenda should be obvious to just about everyone by now.

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I don't necessarily disagree with any of that. However, as long as the numbers are extrapolated instead of actual, I don't think this is ever going to stop. I definitely don't have the answer.
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post #78 of 149 Old 01-27-2014, 10:42 AM
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I don't necessarily disagree with any of that. However, as long as the numbers are extrapolated instead of actual, I don't think this is ever going to stop. I definitely don't have the answer.

This type of extrapolation will always prove correct. There is no variable to consider. We(dozens, hundreds of forum members) have been doing "1m to 2m" and 2m to 1m" extrapolations this way across many forums for decades.....no one ever cried foul because anyone with the slightest bit of experience with acoustical measures knows this is true. This is simply a desperate strawman by one person to attempt to discredit Power Sound Audio. No more, no less.

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post #79 of 149 Old 01-27-2014, 10:43 AM
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I agree with this whole sentence. And I really agree with you on the part that it's a forever long battle. It's funny, if you look back over the last few months you will see multiple threads just like this one. We should just make a sticky thread titled "Pros and Cons of the PSA Chart". That way this argument could be contained and quarantined in a single location. Kind of like the Leper Colonies of old.  

Believe it or not Hop, this is fairly mild compared to the SVS vs. HSU or Axiom vs. SVS battles of old. It's the same tone, but back then you had so many antagonists on both sides that the pages would fill up in minutes. There's just something about subs I guess.
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post #80 of 149 Old 01-27-2014, 10:53 AM
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Believe it or not Hop, this is fairly mild compared to the SVS vs. HSU or Axiom vs. SVS battles of old. It's the same tone, but back then you had so many antagonists on both sides that the pages would fill up in minutes. There's just something about subs I guess.

LOL. True, subs seem to hit a special place in men's hearts. 

 

I wonder if this comes out of the fact that HSU has been around the longest and some people are so loyal that they can't stand to see anyone new come to market? The battles of old must have been pretty intense with more people on both sides of the fray.

 

Shady I have to hand it to you, you have pit bull like tenaciousness. I respect that even though I don't agree with your arguments. 

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post #81 of 149 Old 01-27-2014, 10:58 AM
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BTW,

the "distance versus pressure" extrapolation can be reduced to mathematics...so there really isn't any variable here.

I found an easy to use site for anyone who doesn't want to do the math..smile.gif

http://www.sengpielaudio.com/calculator-distance.htm

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post #82 of 149 Old 01-27-2014, 11:54 AM
 
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What to do? Everybody knows the rules: "Do Not Feed The Trolls."

My understanding, this is law, not a recommendation.

...tongue.gif
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post #83 of 149 Old 01-27-2014, 01:00 PM
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What is also involved in this is the fact that, when placing the mic 2m from the cab, you are 2m + almost another foot from the center of the woofer.  Obviously, distance from the woofer has a dramatic impact on the SPL, as evidence by the 9dB difference between 2m and 1m testing.
This comes to the heart of why CEA specifies a measurement distance of 2 meters. Measuring closer than that introduces a number of variables that affect the result. Those variables all sort themselves out as you move further away from the speaker. Move far enough away and it doesn't matter which way the driver or the port are facing, you can rotate the cab 360 degrees on any plane and the result will always be the same. Even two meters is a closer than preferred, but CEA had to bow to the reality that not everyone has the facilities to measure at more than 2 meters. Danley Labs probably has the best protocol, measuring at 10 meters, where even the largest sub will be a pure point source well beyond the influence of the nearfield condition, and at 100 watts, to see what happens with a real world power input. Guys like Tom and myself who understand how all this works don't lose sleep over it. Those who don't are the ones who waste everyone's time by incessantly picking at nits.
BTW, the difference between 1m and 2m is nominally 6dB. But it might be seen as 9dB based on some of those pesky variables, and if you do see a 9dB difference it's because the 1m reading has been corrupted by one or more of those variables.
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post #84 of 149 Old 01-27-2014, 05:07 PM
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The position Tom is trying to argue against and wants me to have isn't the one I actually hold. I explained in a post yesterday the problems with his extroploation, which is something he well knows about but will never address or concede:
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Originally Posted by shadyJ View Post

It isn't quite that simple, despite what PSA would want you to believe. If the woofer is closer to the mic, you would likely measure a bit more output from the woofer's band, but then you lose output from the port's band since it gets further away. You can see this principle demonstrated in one of the tests done of the Premeir Acoustics PA-150, under the tab 'extended measurements', look at the chart labeled 'orientation comparison', it compares the driver with port facing the mic, woofer facing the mic, and I assume a diagonal measurement of the box where both port and woofer are angled 90 degrees from the mic. Furthermore, if the XV15 were tested with woofer facing the mic, it would also get an increase in the THD measurements because a good chunk of those are masked when the driver is in a down-firing configuration. Since the driver is the primary generator of THD, and since CEA is limited by a THD threshold, measuring the XV15 in a down-firing configuration is doing it a big favor for those tests.

Those other variables are why it is improper to just add a dB to make up for the greater distance of mic from the woofer. Normally I wouldn't really care, I mean I don't think it is a hundred percent honest, but the matter of a decibel or two isn't really much. As I have said before, even a modest change in the weather has been shown to change measurements as much. However, Tom then goes on to use his dishonestly inflated numbers in a comparison where every decibel counts. What's more, that is not the only layer of deception in his shifty comparison charts. He uses other techniques to boost his sub's apparent performance to achieve their so-called 'value rating' against competitors.
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post #85 of 149 Old 01-27-2014, 05:14 PM
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Originally Posted by shadyJ View Post

The position Tom is trying to argue against and wants me to have isn't the one I actually hold. I explained in a post yesterday the problems with his extroploation, which is something he well knows about but will never address or concede:
Those other variables are why it is improper to just add a dB to make up for the greater distance of mic from the woofer. Normally I wouldn't really care, I mean I don't think it is a hundred percent honest, but the matter of a decibel or two isn't really much. As I have said before, even a modest change in the weather has been shown to change measurements as much. However, Tom then goes on to use his dishonestly inflated numbers in a comparison where every decibel counts. What's more, that is not the only layer of deception in his shifty comparison charts. He uses other techniques to boost his sub's apparent performance to achieve their so-called 'value rating' against competitors.

LOL..... how did we all know you had to get your last word in right on cue.... LOL
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post #86 of 149 Old 01-27-2014, 05:20 PM
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But is he wrong about what he said?

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post #87 of 149 Old 01-27-2014, 05:22 PM
 
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Well, actually, yes. Because as of this post, I'm getting the last word in. tongue.gif
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post #88 of 149 Old 01-27-2014, 05:27 PM
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Originally Posted by Hopinater View Post

I wonder if this comes out of the fact that HSU has been around the longest and some people are so loyal that they can't stand to see anyone new come to market? The battles of old must have been pretty intense with more people on both sides of the fray.

I like Hsu's products and appreciate the good service the company has given me in the past, but I am not really beholden to them nor am I defending or advocating them specifically in these arguments. They are good subs but they aren't perfect, and there are competitors who would appear to have a better product for the same price. For example, the VTF1 is the same price as the PB1000, but the PB1000 looks to be a better choice for performance for the most part. If you asked me whether you should get a SVS PC12-Plus or a VTF15h, I would tell you to get a PC12-Plus. However, regarding the subject of this thread, Power Sound Audio is using gamed numbers to put down Hsu's and SVS's subs. If you want me off their case, get them to present their data in a honest and fair manner. Like I said before, I don't just start ripping on PSA out of the blue in these threads, I only get involved when someone refers about PSA's comparison chart specifically, or someone starts ripping on other subs using PSA's slanted take on the data.
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post #89 of 149 Old 01-27-2014, 05:37 PM
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Quote:
Originally Posted by shadyJ View Post

I like Hsu's products and appreciate the good service the company has given me in the past, but I am not really beholden to them nor am I defending or advocating them specifically in these arguments. They are good subs but they aren't perfect, and there are competitors who would appear to have a better product for the same price. For example, the VTF1 is the same price as the PB1000, but the PB1000 looks to be a better choice for performance for the most part. If you asked me whether you should get a SVS PC12-Plus or a VTF15h, I would tell you to get a PC12-Plus. However, regarding the subject of this thread, Power Sound Audio is using gamed numbers to put down Hsu's and SVS's subs. If you want me off their case, get them to present their data in a honest and fair manner. Like I said before, I don't just start ripping on PSA out of the blue in these threads, I only get involved when someone refers about PSA's comparison chart specifically, or someone starts ripping on other subs using PSA's slanted take on the data.

I would say that the only thing I don't really think PSA should have on the chart is the value factor. Everything else on they're chart as far as the competitors is info they've gathered that anyone else would have access too. They haven't fabricated the info for the competitors subs and if they had I'm sure some of those competitors would have something to say about it. And the fact that those same competitors post on these very forums we would have probably read about it by now.
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post #90 of 149 Old 01-27-2014, 06:31 PM
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Quote:
Originally Posted by jbrown15 View Post

I would say that the only thing I don't really think PSA should have on the chart is the value factor. Everything else on they're chart as far as the competitors is info they've gathered that anyone else would have access too. They haven't fabricated the info for the competitors subs and if they had I'm sure some of those competitors would have something to say about it. And the fact that those same competitors post on these very forums we would have probably read about it by now.

Their competitors probably have too much professional tact to outwardly criticize PSA on this. I doubt very much they feel that PSA is presenting an accurate comparison of their subs respective performance, even without the 'value factor'. They will understand that:
A) Averaged CEA measurements give PSA an advantage because of the low quality of their drivers.
B) PSA is using questionable in-house measurements to compare to other data gathered by third parties.
C) CEA 2010 is just one aspect of a sub's performance. It would be like judging cars based on their 0-60 alone.

But hey, there is an easy way to find out how their competitors feel about the way PSA presents their data: you can just ask them. Just shoot an email to any of the companies PSA uses in their comparison guide and ask them if they feel their subwoofer's performance is fairly represented in PSA's comparison guide. It's easy and would only take a couple minutes.
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