The Official HSU VTF-15H Thread - Page 6 - AVS Forum
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post #151 of 5188 Old 11-11-2010, 08:54 AM
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Quote:
Originally Posted by penngray View Post

Sorry but what did I miss about the numbers?? All the data points to the measurements being inaccurate.

Or could it be that Dr Hsu knows a little more about subwoofer design then you do?

Once Audioholics does their testing we will see if it is inaccurate or you could buy one and try and do some reverse engineering.

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post #152 of 5188 Old 11-11-2010, 08:56 AM
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Originally Posted by penngray View Post

Okay maybe but no one can find a 350Watt amp that has 1200 peaks but lets still move on.

Can't tell if you meant you can't find commercially or you can't find a baseline, but this might help the former...

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Originally Posted by Hsu Research Forums View Post

This product has been in development for more than 2 years. Almost everything was designed from the ground up. The driver design, amplifier design, enclosure design, port design, grille design, and feet design were all done in-house from the ground up by Hsu Research. Up until today, all listening tests (and measurements) were done internally at Hsu Research.

It's rare to find numbers actually being boasted so clearly on these forums. A little apprehension is warrented, but given the source and designer of the VTF-15H i'd suspend any doubts until proven otherwise. Not like we're talking AV123 here.
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post #153 of 5188 Old 11-11-2010, 11:43 AM
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Well done Dr Hsu and staff. Looks like another class leading design from one of the truly great subwoofer designers.

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post #154 of 5188 Old 11-11-2010, 12:58 PM
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Quote:
Originally Posted by hometheatergeek View Post

Or could it be that Dr Hsu knows a little more about subwoofer design then you do?

Once Audioholics does their testing we will see if it is inaccurate or you could buy one and try and do some reverse engineering.

I see the thread at Audioholics is 31 pages long already! When does the actual testing take place?
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post #155 of 5188 Old 11-11-2010, 12:59 PM
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Quote:
Originally Posted by penngray View Post

Sorry but what did I miss about the numbers?? All the data points to the measurements being inaccurate.

Penn...Mark Seaton modeled it and made a post in the DIY section:
http://www.avsforum.com/avs-vb/showt...1#post19472561

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post #156 of 5188 Old 11-11-2010, 01:09 PM
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Quote:
Originally Posted by Quaxtros View Post

I see the thread at Audioholics is 31 pages long already! When does the actual testing take place?

They have done some testing already and are testing now but the published results from the shootout is late Dec per Gene's post here.

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post #157 of 5188 Old 11-11-2010, 01:13 PM
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Quote:
Originally Posted by hometheatergeek View Post

They have done some testing already and are testing now but the published results from the shootout is late Dec per Gene's post here.

Thanks for that info.
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post #158 of 5188 Old 11-11-2010, 02:21 PM
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Quote:
Originally Posted by hometheatergeek View Post

They have done some testing already and are testing now but the published results from the shootout is late Dec per Gene's post here.

It would be cool if they could just do a review with the measured specs asap and do the results of the shootout in late December. I know a lot of people would love to see someone get a review out on this sub now.
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post #159 of 5188 Old 11-11-2010, 03:29 PM
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Quote:
Originally Posted by hometheatergeek View Post

Or could it be that Dr Hsu knows a little more about subwoofer design then you do?

Once Audioholics does their testing we will see if it is inaccurate or you could buy one and try and do some reverse engineering.

Obviously he knows more about sub design but Dr. Hsu didnt bypass Science 101 and this sub has NO rocket science in it (no more then any other ported design)....The numbers will show themselves at some point.

Wanna bet $$$ on who is right?? Or is this going to be another "Flat to 10Hz" type of spin

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post #160 of 5188 Old 11-11-2010, 03:32 PM
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Quote:
Originally Posted by cschang View Post

Penn...Mark Seaton modeled it and made a post in the DIY section:
http://www.avsforum.com/avs-vb/showt...1#post19472561

Yep, I know he did, really read his post though

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post #161 of 5188 Old 11-11-2010, 03:37 PM
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Quote:
Originally Posted by JackOften View Post

Can't tell if you meant you can't find commercially or you can't find a baseline, but this might help the former...

I ignore marketing spin so that quote is meaningless. Im already giving them the amp capabilities...its the driver and low end output that does not match up.

Quote:


It's rare to find numbers actually being boasted so clearly on these forums. A little apprehension is warrented, but given the source and designer of the VTF-15H i'd suspend any doubts until proven otherwise. Not like we're talking AV123 here.

CEA2010 is a real standard so Im hoping the did the test properly. There is a great list of subs that have went through that measurement standard so we should expect the same for this sub.

No one is posting anything about AV123.

Its our job to cut through marketing spin and get the real data or atleast some people have to do it because no company is going to do it.

No matter who company or person is (Yes, Dr. Hsu has HUGE respect) there are still consumers with knowledge that should openly question something that is not clear. Im okay if I missed something, Im happy to be corrected but there are some extremely smart guys that have thoughts on it in another thread

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post #162 of 5188 Old 11-11-2010, 03:42 PM
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Quote:
Originally Posted by Rob Tomlin View Post

It would be cool if they could just do a review with the measured specs asap and do the results of the shootout in late December. I know a lot of people would love to see someone get a review out on this sub now.

Do they even have the sub in house yet?
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post #163 of 5188 Old 11-11-2010, 03:52 PM
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Quote:
Originally Posted by penngray View Post

Yep, I know he did, really read his post though

Remember, the test was done with both ports open, so the native tune of the box, which correlates well to what Mark found.

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post #164 of 5188 Old 11-11-2010, 03:58 PM
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I believe it's possible that the HSU could meet the CEA numbers mentioned. Why? Because when adjusted 6db down to allow for the 2m distance, they are essentially the same numbers that the PB13 have already been tested for. Nobody disputes the PB13's numbers. Assuming equal efficiency as the PB13 (who knows, it may be higher because of the bigger woofer), if the HSU amp can manage as much short-term power as the SVS, then it should make about the same numbers.
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post #165 of 5188 Old 11-11-2010, 04:09 PM
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Maybe I'm missing a point or two here, but what's purpose of measuring a second or two burst? wouldn't measuring continuous levels make the most practical sense?
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post #166 of 5188 Old 11-11-2010, 04:16 PM
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Maybe I'm missing a point or two here, but what's purpose of measuring a second or two burst? wouldn't measuring continuous levels make the most practical sense?

They are both equally important in my opinion.
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post #167 of 5188 Old 11-11-2010, 04:31 PM
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Quote:
Originally Posted by JoshKo View Post

Maybe I'm missing a point or two here, but what's purpose of measuring a second or two burst? wouldn't measuring continuous levels make the most practical sense?

Continuous is definitely more of a torture test, not necessarily real world. But the point is not what kind of test is better, but to be able to standardize so that tests are comparable.

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post #168 of 5188 Old 11-11-2010, 04:36 PM
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Quote:
Originally Posted by mojomike View Post

I believe it's possible that the HSU could meet the CEA numbers mentioned. Why? Because when adjusted 6db down to allow for the 2m distance, they are essentially the same numbers that the PB13 have already been tested for. Nobody disputes the PB13's numbers. Assuming equal efficiency as the PB13 (who knows, it may be higher because of the bigger woofer), if the HSU amp can manage as much short-term power as the SVS, then it should make about the same numbers.

Well, I think people have decided to challenge the VTF-15H's capabilities because of its price point, and when people feel threatened, they are not usually logical.

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post #169 of 5188 Old 11-11-2010, 04:45 PM
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Feeling threatened by subwoofer output claims is not logical to begin with.
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post #170 of 5188 Old 11-11-2010, 04:49 PM
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Quote:
Originally Posted by mojomike View Post

Feeling threatened by subwoofer output claims is not logical to begin with.

Agreed.

But if you look at a certain company's forum, you can see that someone is threatened by something.

Maybe it's the VTF-15H's real nice finish while their's is just a painted box.

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post #171 of 5188 Old 11-11-2010, 05:27 PM
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Quote:
Originally Posted by cschang View Post

Agreed.

But if you look at a certain company's forum, you can see that someone is threatened by something.

Maybe it's the VTF-15H's real nice finish while their's is just a painted box.

Ohhhhhhhhhhhhhhh.....
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post #172 of 5188 Old 11-11-2010, 05:30 PM
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Quote:
Originally Posted by penngray View Post

Obviously he knows more about sub design but Dr. Hsu didnt bypass Science 101 and this sub has NO rocket science in it (no more then any other ported design)....The numbers will show themselves at some point.

Wanna bet $$$ on who is right?? Or is this going to be another "Flat to 10Hz" type of spin

But I actually get 10 Hz out of my subs. I have witnesses.

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post #173 of 5188 Old 11-11-2010, 06:00 PM
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Quote:
Originally Posted by penngray View Post

I ignore marketing spin so that quote is meaningless. Im already giving them the amp capabilities...its the driver and low end output that does not match up.



CEA2010 is a real standard so Im hoping the did the test properly. There is a great list of subs that have went through that measurement standard so we should expect the same for this sub.

No one is posting anything about AV123.

Its our job to cut through marketing spin and get the real data or atleast some people have to do it because no company is going to do it.

No matter who company or person is (Yes, Dr. Hsu has HUGE respect) there are still consumers with knowledge that should openly question something that is not clear. Im okay if I missed something, Im happy to be corrected but there are some extremely smart guys that have thoughts on it in another thread

So I just want to get this straight. You're speculating with about... say half the total picture(i haven't seen any data from you on how cabinet design can impact SPL's, that's a start...) that the VTF-15h won't hit the numbers they are boasting. You're so sure they can't be accurate (again, with about only half the picture...) that you're openly stating they can't be accurate

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Originally Posted by pennygray View Post

Sorry but what did I miss about the numbers?? All the data points to the measurements being inaccurate.

Meanwhile a ID speaker company is so confident of the same sub that they've sent the VTF-15h to Audioholics for a Shootout . That's putting your money where your mouth is.

It would be business suicide to put up a false set of measurements that land no where near what's being touted.

I'm starting to speculate that you don't know nearly as much as act like you do in the forums, but we'll know the truth come December when the shootouts results are published, won't we?
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post #174 of 5188 Old 11-11-2010, 06:32 PM
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Quote:
Originally Posted by penngray View Post

All the data points to the measurements being inaccurate.

Dr. Hsu recently pulled out a random new production unit and got even a tad higher output than what I had quoted. In Ported Max Output Mode he measured 124-125dB from 40-80Hz, 122dB @ 31.5Hz, 119dB @ 25Hz, 114dB @ 20Hz maximum clean peak output using the CEA2010 stepped harmonic distortion limits.

The CEA2010 software is pretty straightforward. One plays tone bursts at 1/3-octave spaced frequencies (80Hz/63Hz/50Hz/40Hz/31.5Hz/25Hz/20Hz/etc.), and tries to achieve as high a sound pressure level as possible while still passing within the CEA2010 stepped harmonic distortion limits. If one exceeds any of the stepped harmonic distortion limits, then the software shows "Fail" at that particular harmonic. It is very easy to tell the difference between "Pass" and "Fail"!!!

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post #175 of 5188 Old 11-11-2010, 06:47 PM
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Quote:
Originally Posted by penngray View Post

Obviously he knows more about sub design but Dr. Hsu didnt bypass Science 101 and this sub has NO rocket science in it (no more then any other ported design)....The numbers will show themselves at some point.

Wanna bet $$$ on who is right??

Is it too late to take you up on that bet?

Quote:
Originally Posted by Pete_Hsu View Post

Dr. Hsu recently pulled out a random new production unit and got even a tad higher output than what I had quoted. In Ported Max Output Mode he measured 124-125dB from 40-80Hz, 122dB @ 31.5Hz, 119dB @ 25Hz, 114dB @ 20Hz maximum clean peak output using the CEA2010 stepped harmonic distortion limits.

The CEA2010 software is pretty straightforward. One plays tone bursts at 1/3-octave spaced frequencies (80Hz/63Hz/50Hz/40Hz/31.5Hz/25Hz/20Hz/etc.), and tries to achieve as high a sound pressure level as possible while still passing within the CEA2010 stepped harmonic distortion limits. If one exceeds any of the stepped harmonic distortion limits, then the software shows "Fail" at that particular harmonic. It is very easy to tell the difference between "Pass" and "Fail"!!!

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post #176 of 5188 Old 11-11-2010, 06:48 PM
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Quote:
Originally Posted by cschang View Post

Penn...Mark Seaton modeled it and made a post in the DIY section:
http://www.avsforum.com/avs-vb/showt...1#post19472561

I just posted a response there: http://www.avsforum.com/avs-vb/showt...8#post19474448

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post #177 of 5188 Old 11-11-2010, 06:55 PM
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By the way, Dr. Hsu was kind enough to provide a picture of VTF-15H Satin Black with grille on. Do note that it will look much more black and not gray in person!
LL

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post #178 of 5188 Old 11-11-2010, 06:55 PM
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The CEA has specific software for testing?

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post #179 of 5188 Old 11-11-2010, 07:14 PM
 
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Quote:
Originally Posted by mojomike View Post

I believe it's possible that the HSU could meet the CEA numbers mentioned. Why? Because when adjusted 6db down to allow for the 2m distance, they are essentially the same numbers that the PB13 have already been tested for. Nobody disputes the PB13's numbers. Assuming equal efficiency as the PB13 (who knows, it may be higher because of the bigger woofer), if the HSU amp can manage as much short-term power as the SVS, then it should make about the same numbers.

I posted the same thing in the DIY section regarding this sub.
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post #180 of 5188 Old 11-11-2010, 07:18 PM
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Quote:
Originally Posted by penngray View Post

I ignore marketing spin so that quote is meaningless. Im already giving them the amp capabilities...its the driver and low end output that does not match up.

Quote:
Originally Posted by Mark Seaton View Post

A quick model I did of an approximation of what I would guess is close to their 15" driver in a box approximately that size tuned to 22Hz with 1400W correlates pretty well with the CEA peak output numbers listed. I doubt that output could be sustained for more than a few seconds, but it is certainly within the realm of possibility. It also looks as though the 19-35Hz range will take a noticeable hit in the same output measurements when the 16Hz (one port plugged) mode is engaged. The triangular ports are an interesting choice. The flaring on the outlet side looks like ~3/4" radius which seems a bit conservative, so it should be interesting to see what is observed in terms of port airflow noise at those higher levels. The triangle profile holds both benefits and detriments as compared to a round or rectangular ports, so the observations from users will be interesting to see. This is again a case where measurements really need associated tester observations to insure the testing doesn't overlook relevant details of a differing design.

For someone who said it doesn't add up, someone who actually knows something about subwoofers (without a vested interest) says it can.

Thanks for adding 0 to this thread penngray. You took the science right out of it with your hunches and speculation.
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