The Official HSU VTF-15H Thread - Page 6

Originally Posted by penngray

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

Originally Posted by penngray

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

Originally Posted by Hsu Research Forums

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.

Originally Posted by hometheatergeek

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.

Originally Posted by penngray

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

Originally Posted by Quaxtros

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

Originally Posted by hometheatergeek

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.

Originally Posted by hometheatergeek

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.

Originally Posted by hometheatergeek

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.

Originally Posted by cschang

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

Originally Posted by JackOften

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

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.

Originally Posted by Rob Tomlin

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.

Originally Posted by penngray

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

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?

Originally Posted by JoshKo

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?

Originally Posted by mojomike

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.

Originally Posted by mojomike

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

Originally Posted by cschang

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.

Originally Posted by penngray

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

Originally Posted by penngray

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

Originally Posted by pennygray

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

Originally Posted by penngray

All the data points to the measurements being inaccurate.

Originally Posted by penngray

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??

Originally Posted by Pete_Hsu

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"!!!

Originally Posted by cschang

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

Originally Posted by mojomike

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.

Originally Posted by penngray

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.

Originally Posted by Mark Seaton

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.