Official HSU ULS-15 Thread - Page 16 - AVS Forum
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Old 05-19-2010, 05:29 PM
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Originally Posted by Pete_Hsu View Post

Hi Gordon,
It's hard to tell at first due to the y-axis scale, but there is indeed a very significant deep bass suckout. With mic 1ft away from the cone, the response @ 20Hz is 6db down (!) compared to 60Hz, and 3-4dB down compared to 40Hz. When measured outside and away from reflective surfaces, the ULS-15 is at most 1db down @ 20Hz vs 60Hz and 40Hz. This inflates the 2nd and 3rd order harmonic distortion products with 20Hz fundamental tone. Note that the harmonic distortion was measured with mic 1 ft away from the cone, not 1m or 2m, so that is the curve we need to look at.

Hi Pete,
Why people measure at 1 foot comparing to 1 m or 2 m? To minimize the influence of room modes, correct?
Room has it's own resonances on the same main frequencies of resonances, no matter how you move mic around it, but the final FR depends on the combination of modes at the point where MIC is located.

Such as reviewers used 1 foot distance and AP system, we can use this information: http://ap.com/kb/show/156
Quote:


With a distance of one meter between the mic and the speaker, and given that sound travels 1116.4 feet (340.29 meters) per second at sea level, the first reflection will arrive about 5 ms after the direct sound. This means that results over approximately 200 Hz will be reliable, and results below about 200 Hz will be uncertain (they may be OK, or may be tainted by reflections).

It means results for 1 foot distance are reliable over about 143 Hz, correct? We shouldn't count even first reflections, not talking about other modes. But at 20 Hz there is another story, so we have to be careful.

But - there is a solution (AP is awesome, of course). Such as for 1 foot the first reflected signal will arrive about 7 ms after the direct sound, in AP it is pretty easy to make a re-calculation:
Quote:


Automatically Recalculating the Measurements
By moving the time window cursor in either the ETC or the IR view to a position just before the first reflection, any reflections will be excluded from the measurements. Each measurement (frequency response, phase, distortion, etc.) will be automatically recalculated based on the new time window—without needing to rerun the test
... Note that although eliminating reflections will give the most accurate and repeatable results, there are times when their inclusion may be desirable to in order to better represent the real world conditions where the speaker will actually be used.

Do you think that reviewers didn't eliminate the reflections for their measurements using this method? If so, it is sad ...
If they did it - what kind of modes, reflections and accordingly, bass sickouts are we talking about even at 20 Hz?

Quote:


In our own demo room, with mic 1 ft away from the woofer cone, THD is 6% @ 20Hz @ 100dB.

Why don't you publish such graphs - right here, for example? Everyone will LOVE to see them.

Quote:


Note that the ULS-15 measurements in that review are not even directly comparable to F113 and some other subs that were measured by the same reviewer. If you compare the in-room frequency response curves side by side, notice the large differences in frequency response between ULS-15 and F113 in the 25-63Hz region, even though both of these subs are quite flat in this region when the frequency response is measured outside and away from reflective surfaces.

It looks that in your opinion such 1-foot AP in-room measurements are flawed. If they don't provide reliable - comparable - results, we should use only free field measurements, is it correct? Why do you use these flawed results on your own website? http://www.hsuresearch.com/products/uls15.html
http://www.hsuresearch.com/reviews/S...aterReview.pdf

It doesn't seem logical to me, Sir.

Can you (please) provide such free field measurements for ULS-15, so we all will be able to compare them with other sub woofer measurement results, performed by Ilkka, Slartibartfas, and other people in a free field?

Quote:


The ULS-15 has very high clean output capability in the 25-63Hz region, a solid 2-3db higher clean output in this region compared to VTF-3 MK3 in extended bass mode. If one is primarily interested in max clean output at 20Hz and below, the VTF-3 MK3 would be a better choice.
Sincerely,

Again, we would LOVE to see the graphs.

VTF-3 Mk3 (in extended bass mode, as you suggested) is not the best example to use for a clean bass at 20 Hz according to Ilkka's measurements, AFAIK
http://personal.inet.fi/private/zipm...20me%20thd.png
It is pretty odd that ULS-15 can be worse at this frequency ... even for a manufacturer.
With best regards

Truth, like gold, is to be obtained not by its growth, but by washing away from it all that is not gold. Lev Tolstoy
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Old 05-19-2010, 07:19 PM
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Hi Gordon,

To be quite frank, I am always a bit wary when comparing measurements taken in-room, but it is what it is. Sometimes it is neither convenient nor practical to measure outdoors. Also, a good review consists of much more than one low frequency measurement. A good review will include both subjective impressions and measurements taken at a variety of frequencies. Now, we may take issue with some measurements, but that doesn't mean that the review is not useful in the grand scheme of things.

The VTF-3 MK3 is no slouch in terms of maximum clean output @ 20Hz. The max peak clean output capability (using the CEA2010 stepped harmonic distortion limits) @ 20Hz @ 1m measured outside and away from reflective surfaces is ~112dB in the max output mode. Keep in mind that this was with driver and port centroid equidistant from mic, which was not the case in other reviews.

With respect to posting our own measurements on our website, that is a reasonable request. I hope to do a big measurement session later in the year to get as accurate a comparison between our subs as possible. I am pretty busy right now with the day-to-day grind, but it's on my to-do list.

Sincerely,

Pete - Hsu Research
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Old 05-19-2010, 08:43 PM
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Quote:
Originally Posted by Pete_Hsu View Post

Hi Gordon,
To be quite frank, I am always a bit wary when comparing measurements taken in-room, but it is what it is. Sometimes it is neither convenient nor practical to measure outdoors. Also, a good review consists of much more than one low frequency measurement. A good review will include both subjective impressions and measurements taken at a variety of frequencies. Now, we may take issue with some measurements, but that doesn't mean that the review is not useful in the grand scheme of things.

Other useful things can be valuable, though subjective listening impressions are useless for me - these impressions always different for different individuals depending on a room conditions, emotional and preference feelings - even with or without a glass of wine .
Unfortunately no one does DBT for sub woofers, and it is the only type of a listening test I can accept as a proof of audible difference, sorry.
If something can produce a perfect sound quality at all frequencies and at some frequency it produces a lot of audible distortions, it is still imperfect for me, because my sources normally have such frequencies and of course, I will notice the imperfection and will not be happy. May be I will listen at a different (lower) level and will be happy, but when you have something to compare, you always look for a better product - and of course, better price.

Quote:


The VTF-3 MK3 is no slouch in terms of maximum clean output @ 20Hz. The max peak clean output capability (using the CEA2010 stepped harmonic distortion limits) @ 20Hz @ 1m measured outside and away from reflective surfaces is ~112dB in the max output mode. Keep in mind that this was with driver and port centroid equidistant from mic, which was not the case in other reviews.

Please provide a source of such information, whatever I can see on the Ilkka's graphs and/or tables is at least 5 dB different (and significantly different regarding distortions):
http://www.hometheatershack.com/foru...mpilation.html - it is 101.3 dB normalized to 2 m, therefore it is 107.3 dB normalized to 1 m ... which is 5 dB lower comparing to your statement.

MAX output doesn't give me enough information without knowing level and components structure of THD, it can be very audible 50% of 3rd and 5th harmonic in one case and below 10% of second harmonic (inaudible) in another case (if a soft limiter is used).

What is the reason to have 107.3 dB @1m @20 Hz with over 50% THD - and it looks pretty close to that level at 107 dB (limited at about 107 dB @20 Hz, though at 48 Hz it is about 110 dB) in VTF-3 MK3 Maximum output mode at 20 Hz http://personal.inet.fi/private/zipm...0mo%20thd.png?
Who can handle such level of distortions? It is not a "maximum clean output", at least for me, sorry.

For example PB12-NSD can do 108 dB @1m @20 Hz with only 3% THD (102 dB @2 m@ 20Hz) http://www.hometheatershack.com/foru...mpilation.html ... It has 15% at 28 Hz, but VTF-3 Mk3 has it way over 30% at the same level and frequency!
http://personal.inet.fi/private/zipm...2nsd%20thd.png
http://personal.inet.fi/private/zipm...20mo%20thd.png

Quote:


With respect to posting our own measurements on our website, that is a reasonable request. I hope to do a big measurement session later in the year to get as accurate a comparison between our subs as possible. I am pretty busy right now with the day-to-day grind, but it's on my to-do list.
Sincerely,

Thanks, I'll be glad to review your tests as soon as they will be published. Best regards!

Truth, like gold, is to be obtained not by its growth, but by washing away from it all that is not gold. Lev Tolstoy
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Old 05-19-2010, 10:15 PM
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Hi Gordon,

While subjective impressions may be meaningless to you, most of our customers find some value in subjective impressions. To each his own I suppose.

The source of my data is of course Hsu Research (I was not involved in the measurement). The differences in the data are easy to explain: ~6dB difference between 2m and 1m measurement distance, ~3dB difference between RMS and peak value, and the remainder due to differences in mic position (our mic was equidistant from driver and port centroid) and other misc variables.

One can spin total harmonic distortion however one wishes. We could have easily kept THD low by making a simple mod to the amplifier. Even so, from the review, the VTF-3 MK3 has ~106 dB [RMS] @1m @20 Hz with less than 20% THD. It is not correct to say that the competitor sub has 108 dB [RMS] @1m @20 Hz with only 3% THD. The THD at that SPL is much higher than that (albeit still lower THD than the -3), but it is not possible from the available review data to determine the actual THD % at that [108dB] sound pressure level due to the severe output compression at the high sweep levels.

That said, it is really irrelevant to look at total harmonic distortion when looking at CEA2010 max clean output. The whole purpose of the CEA2010 standard is to provide stepped distortion limits based on audibility of harmonic distortion (which is based on harmonic distortion order and %). I'd say that overall, the VTF-3 MK3 compares very favorably with respect to max clean CEA2010 output and frequency response linearity. If anything, the max clean output in that review is 1-2dB lower than it should be due to mic not being equidistant from driver and port centroid. So that would actually result in the VTF-3 MK3 having MORE max clean CEA2010 output @ 20Hz than the competitive model. And the VTF-3 MK3 has been improved since that review first came out.

We are getting way way off-topic here considering the thread title. Feel free to PM or email me if you have more questions/comments. Thanks

Sincerely,

Pete - Hsu Research
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Old 05-20-2010, 10:00 AM
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Quote:
Originally Posted by Pete_Hsu View Post

Hi Gordon,
While subjective impressions may be meaningless to you, most of our customers find some value in subjective impressions. To each his own I suppose.

Hi Pete,
I didn't say they are meaningless, I said they are useless a a proof of difference in sounding of discussed devices. As an example - lets say we are talking about ULS-15 and discuss it's deeper bass comparing to F113. I can't accept it as a proof unless somebody claiming the difference performed a DBT - or provided the results of measurements.

Quote:


The source of my data is of course Hsu Research (I was not involved in the measurement). The differences in the data are easy to explain: ~6dB difference between 2m and 1m measurement distance, ~3dB difference between RMS and peak value, and the remainder due to differences in mic position (our mic was equidistant from driver and port centroid) and other misc variables.

Thanks for the explanation.

Quote:


One can spin total harmonic distortion however one wishes. We could have easily kept THD low by making a simple mod to the amplifier. Even so, from the review, the VTF-3 MK3 has ~106 dB [RMS] @1m @20 Hz with less than 20% THD.

There is no reason to spin anything, we are just discussing the graphs. You are absolutely correct, according to the graphs it can do it. What is also good, at this level and frequency about 16% is 2nd harmonic and 9% is 3rd.

Quote:


It is not correct to say that the competitor sub has 108 dB [RMS] @1m @20 Hz with only 3% THD. The THD at that SPL is much higher than that (albeit still lower THD than the -3), but it is not possible from the available review data to determine the actual THD % at that [108dB] sound pressure level due to the severe output compression at the high sweep levels.

We all know that in a free field recalculation of 2 m distance to 1 m gives us additional 6 dB, correct? I got 102 dB from this table http://www.hometheatershack.com/foru...mpilation.html for PB-12ISD (new) and added 6 dB - it looks like 108 dB.

But - looking at the graphs we can definitely see only 100 dB due to compression, therefore you are right, it should be 106 dB RMS @1 m, not 108 dB. As we have decided to compare 106 dB levels @1m @20Hz, lets take a look on the graphs of distortions:
http://personal.inet.fi/private/zipm...2nsd%20thd.png
http://personal.inet.fi/private/zipm...thd%20comp.png
It looks for me as 3% (may be 3.2%, not more) @20 Hz, which is presented by 2.5% of 2nd and 1.8% of 3rd harmonic.
You are right, we should talk about 106 dB RMS @1m @20 Hz @3% THD for PB-12ISD, or alternatively 100 dB @2m @20 Hz @3% THD comparing to 106 dB RMS @1m @20 Hz @20% THD for VTF-3 MK3 (max output mode) or, alternatively 100 dB@2m @20 Hz @20% THD. Thanks for your correction on 2 dB difference - basically in both cases.

Quote:


That said, it is really irrelevant to look at total harmonic distortion when looking at CEA2010 max clean output. The whole purpose of the CEA2010 standard is to provide stepped distortion limits based on audibility of harmonic distortion (which is based on harmonic distortion order and %). I'd say that overall, the VTF-3 MK3 compares very favorably with respect to max clean CEA2010 output and frequency response linearity.

If we just compare the results from Ilkka's table, it is 101.3 dB for VTF-3 MK3 and 102 dB for PB-12ISD, correct? It is almost the same level, but of course the definition of "max clean output" with 2nd a@ -10 dB limit, 3rd @ -15 dB limit, etc. doesn't sound good to me - though such as it is definition of the CEA2010 standard, you are absolutely correct regarding this point. Thank you.

Quote:


If anything, the max clean output in that review is 1-2dB lower than it should be due to mic not being equidistant from driver and port centroid. So that would actually result in the VTF-3 MK3 having MORE max clean CEA2010 output @ 20Hz than the competitive model. And the VTF-3 MK3 has been improved since that review first came out.

Again, no data - comparing to pure Ilkka's results, mic was in the same position for all measured - and compared - devices, so it is not the issue, Sir.

Quote:


We are getting way way off-topic here considering the thread title. Feel free to PM or email me if you have more questions/comments. Thanks
Sincerely,

You are absolutely right. You have raised the point about VTF-3 MK3, it is definitely off-topic in this thread. Thanks.

Truth, like gold, is to be obtained not by its growth, but by washing away from it all that is not gold. Lev Tolstoy
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Old 05-20-2010, 11:31 AM
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Hi, Gordon:

Don't you find it strange that even when measurements are that important to people, HSU does not publish their graphs, and yet HSU is the oldest (since 1991- 20years) and one of the most respected sub ID companies?

Maybe you can send an email directly to Dr. Poh Ser Hsu and discuss the graphs with him. I am sure he knows the answer to all of your questions.

At the end, what counts is that HSU is a company of great cs and great products. They have not copied any design, product, name, etc from any company. Nor have had any amp/driver problem in 20 years that they didn't took care of.

They are not copycats, and Dr.Hsu knows how to mod/manipulate an amp(electronically) and/or driver/box to make a very flat FR, without outsourcing. That is a fact. It is not a company of getting a box with a 1,000 watt amp, and throwing a driver on the mix to see how it sounds.

Sincerely,

Cacimar Hernandez
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Old 05-20-2010, 12:02 PM
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Originally Posted by cacihome View Post

Hi, Gordon:

Don't you find it strange that even when measurements are that important to people, HSU does not publish their graphs, and yet HSU is the oldest (since 1991- 20years) and one of the most respected sub ID companies?

Maybe you can send an email directly to Dr. Poh Ser Hsu and discuss the graphs with him. I am sure we knows the answer to all of your questions.
Sincerely,

Hi Cacihome,

You know, manufacturers don't normally publish their measurements, sometimes only FR graphs. I assume it is a liability issue - if they publish something officially, they have to be responsible for it. It is difficult to control everything.

Our audiophile community is really lucky to have such people as Illka (hometheatershack) - unfortunately, he is gone to work for Genelec, though most probably we will see some awesome stuff made by Genelec for consumer market in the nearest future .

We still have Slartibartfast (avtalk), some other nice people. Without them we would still continue to read paid reviews with subjective listening impressions of reviewers and exchange opinions in different forums about our subjective listening impressions in our own rooms

Now we have an opportunity to find out "who is who" and at least make our own conclusions objectively For me as a consumer it is not really important who did what in the past as soon as I have and can use a good product. There are plenty of lawyers around to argue about such stuff.

Basically I am quite satisfied with responses of Mr. Pete Hsu and see no reason to contact Dr. Poh Ser Hsu directly. There is enough information for me to make some conclusions regarding ULS-15. I am currently very interested in a linear motor concept and collect all information about THD results of equipment with LMS drivers.
Thanks for your advice though, I appreciate it!
Best regards

Truth, like gold, is to be obtained not by its growth, but by washing away from it all that is not gold. Lev Tolstoy
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Old 05-20-2010, 12:10 PM
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Originally Posted by Gordon McGregor View Post

Hi Cacihome,

You know, manufacturers don't normally publish their measurements, sometimes only FR graphs. I assume, it is a liability issue - if they publish something officially, they have to be responsible for it. It is difficult to control everything.

Our audiophile community is really lucky to have such people as Illka (hometheatershack) - unfortunately, he is gone to work for Genelec, though most probably we will see some awesome stuff made by Genelec in the nearest future for consumer market .

We still have Slartibartfast (avtalk), some other nice people. Without them we would still continue to read paid reviews with subjective listening impressions of reviewers and exchange opinions in different forums about our subjective listening impressions in our own rooms
Now we have an opportunity to find out "who is who" and at least make our own conclusions objectively

Basically I am quite satisfied with responses of Mr. Pete Hsu and see no reason to contact Dr. Poh Ser Hsu directly. There is enough information for me to make some conclusions about ULS-15. Thanks for your advice though, I appreciate it!
Best regards

Hi, Gordon:

I agree with some things you said. But...

1. Not all reviews are paid.
2. The reviewer, whether professional or not, will always be biased to some brand, depending on his perception of things...It is just human nature.

Take care man,

Cacimar Hernandez
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Old 05-20-2010, 12:31 PM
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Originally Posted by cacihome View Post

Hi, Gordon:

I agree with some things you said. But...

1. Not all reviews are paid.
2. The reviewer, whether professional or not, will always be biased to some brand, depending on his perception of things...It is just human nature.

Take care man,

Cacihome,

I agree with everything you said. Of course, not all reviews are paid - I was talking about those fancy ones in glossy magazines, which had no useful data but only subjective impressions and attractive pictures
Even some paid reviews are extremely valuable in my opinion - for example, performed by D. B. Keele. He usually provides extremely valuable measurements, and I don't really care if he is biased or not if those measurements are correct and can be repeated by anyone.

And every reviewer is somehow biased to some brand (or brands), based on his personal knowledge and experience - which is based (accordingly) on objective measurements and / or subjective opinions, this is also true.

You take care too, Sir Aren't we going off-topic even further?

Truth, like gold, is to be obtained not by its growth, but by washing away from it all that is not gold. Lev Tolstoy
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Old 05-20-2010, 01:26 PM
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Hi Gordon,

Quote:
Originally Posted by Gordon McGregor View Post

but of course the definition of "max clean output" with 2nd a@ -10 dB limit, 3rd @ -15 dB limit, etc. doesn't sound good to me - though such as it is definition of the CEA2010 standard, you are absolutely correct regarding this point. Thank you.

I suppose that the distortion limits set by the CEA2010 standard are debateable, but it is my understanding that there was a large amount of research that went into determining these stepped distortion limits, and one can certainly make the case that this is a more thoughtful approach than simply looking at total harmonic distortion percentage with no regard to weighting of higher order vs lower order harmonic distortion products. But again, unquestionably a debateable and complex subject.

Anyway, back to regularly scheduled programming...

Pete - Hsu Research
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Old 05-20-2010, 02:16 PM
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Quote:
Originally Posted by Gordon McGregor View Post

Basically I am quite satisfied with responses of Mr. Pete Hsu and see no reason to contact Dr. Poh Ser Hsu directly.

Gordon/Alex...you should visit the new Hsu offices. It is much nicer than the offices you visited a while back, and still close to Irvine.

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Old 05-20-2010, 02:19 PM
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Originally Posted by Pete_Hsu View Post

Hi Gordon,
I suppose that the distortion limits set by the CEA2010 standard are debateable, but it is my understanding that there was a large amount of research that went into determining these stepped distortion limits, and one can certainly make the case that this is a more thoughtful approach than simply looking at total harmonic distortion percentage with no regard to weighting of higher order vs lower order harmonic distortion products. But again, unquestionably a debateable and complex subject.

Anyway, back to regularly scheduled programming...

Hi Pete,

They are definitely debatable taking in consideration the following:
http://www.audioholics.com/education...ibility-part-3
http://www.aes.org/e-lib/browse.cfm?elib=12996
http://www.aes.org/e-lib/browse.cfm?elib=14232
http://www.poonshead.com/articles.html and specifically this graph:
http://www.poonshead.com/harmonics2.gif - perception of 2nd harmonic at 2% and 3rd at 0.1% ... 20 times or 26 dB difference!!! comparing to only 5 dB difference in CEA2010!

Such I personally had been able to DBT the difference in harmonic distortions just replacing 3 OP AMPS per channel http://members.cox.net/alex_lat/Tests/DBT.JPG in my receiver measuring the difference in THD (taking the level of each harmonic) http://members.cox.net/alexhardware/...harmonics2.gif and then plenty of people confirmed my positive results by their subjective opinions (hundreds of people), I personally believe that Rupert Neve's graph is reasonable, at least for distortions in electronics. This is why I believe that levels of limits in CEA2010 needs to be corrected.

Best regards and good luck with programming

Truth, like gold, is to be obtained not by its growth, but by washing away from it all that is not gold. Lev Tolstoy
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Old 05-23-2010, 12:52 AM
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Finally got my baby up and as usual underwhelmed by it to start. I am not worried though since I have done nothing to it but plugged it in so tomorrow when I send the pics I will you guys know how sweet it sounds.
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Old 05-23-2010, 10:32 AM
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ok so i was wrong......AGAIN. finally set up everything and ran MCACC and it still is underwhelming. why do i always have problems dealing with this sub? i placed the sub in the exact same place as i had my energy sub and the ULS sounds either similar or less impactful as the energy sub. why is this happening? i dont care if ppl say i like boomy bass or whatever but i am thinking if i placed this sub in the exact same position as my other small budget sub it should be louder,tighter and better.

P.S Al, i gave you a call and didnt get you.
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Old 05-23-2010, 11:55 AM
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Originally Posted by Kimwyn View Post

ok so i was wrong......AGAIN. finally set up everything and ran MCACC and it still is underwhelming. why do i always have problems dealing with this sub? i placed the sub in the exact same place as i had my energy sub and the ULS sounds either similar or less impactful as the energy sub. why is this happening? i dont care if ppl say i like boomy bass or whatever but i am thinking if i placed this sub in the exact same position as my other small budget sub it should be louder,tighter and better.

P.S Al, i gave you a call and didnt get you.

You might explain your process in setting up your sub, as well as the dimensions of your room and areas that it opens up to. A sketch would be a great start, if possibly.

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Old 05-23-2010, 01:48 PM
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MCACC has always set the sub at fairly low levels for my tastes, much like Audyssey. maybe it's just the microphone I am using though. Can you manually boost the sub level with in your receiver? That is what I always do after running either MCACC or Audyssey, but I like to run it a little hot anyway. Check in your receiver where it set the sub level at with respect to the other channel levels. Make sure to have any kind of normalization processing disabled too. Also try to run some test tones, here is a pack of test tones free for download, but be careful with the very low tones, if you play them back at loud levels they will bottom your sub out- read the readme that comes with it. Run some of those bass tones to see how it sounds, from 20 hertz and up. If those tones sounds decent, than your receiver is messing up the bass when it is playing back regular material. Let us know how it goes.
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Old 05-23-2010, 03:58 PM
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Kimwyn, please send an email to saleshsuresearchcom with some info on your room layout, and I will help you out there.

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Old 05-23-2010, 05:05 PM
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ok so i was wrong......AGAIN. finally set up everything and ran MCACC and it still is underwhelming. why do i always have problems dealing with this sub? i placed the sub in the exact same place as i had my energy sub and the ULS sounds either similar or less impactful as the energy sub. why is this happening? i dont care if ppl say i like boomy bass or whatever but i am thinking if i placed this sub in the exact same position as my other small budget sub it should be louder,tighter and better.

P.S Al, i gave you a call and didnt get you.

Sorry Kimwyn. I was trying to catch up on house chores since I just got back from my two week job in St Louis late Friday. However I am concerned with the cost of you calling me. I do not know about international calls on my cell. Any insight gentlemen of this thread? You have many an owner on this thread and we are all here to help. Let's take it step by step and we all will be able to help dial in the ULS-15 for you.

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Old 05-23-2010, 05:56 PM
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Ok below i have attached a sketch of my room and everything in it. The subwoofer is in the top left hand corner. The big rectangle in the middle is my bed. To the left of it is the DVD rack and to the right of it is a set of chester drawers and to the right of that is a built in wardrobe.On the wall by the DVD rack is a window with full curtains and the wall by the bed also has a window with curtains. The door to the bedroom is at the top right hand corner. I only have 2 other placement options and that is next to the DVD rack or to the right of the right channel speaker. I would really appreciate all the help i can get. The room is 15'x10'x8' which is very small for this subwoofer which means it should be overkill in this situation. As i have said before i have set up one of these in a room twice as large as mine and it was definitely louder and much more impact could have been felt. If it is any help i have mine on the metal feet that were provided and the other one i set up was not on any feet, it was sitting directly on the floor. Any help is appreciated.
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Old 05-23-2010, 06:07 PM
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Thanks Kimwyn. May I ask where is the doorway opening located?

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Old 05-23-2010, 06:11 PM
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Please see below
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Old 05-23-2010, 06:20 PM
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Try placing the subwoofer in the lower left corner of the picture (with woofer firing directly towards the bed), and leave the door open up front. Make sure to set distance settings for speakers/subwoofer appropriately on the receiver, and set all speakers to 'Small' with 80Hz crossover all around to start. On the sub amp, set ULF trim to 50Hz, crossover switch to 'Out' to start, and experiment with the phase switch.

I suggest adding an MBM-12 MK2 at some point if possible. This will help to give you a flatter in-room response, and punchier mid/upper bass too.

Sincerely,

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Old 05-23-2010, 08:16 PM
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Originally Posted by Kimwyn View Post

i placed the sub in the exact same place as i had my energy sub and the ULS sounds either similar or less impactful as the energy sub.....i am thinking if i placed this sub in the exact same position as my other small budget sub it should be louder,tighter and better.

Bad assumption.
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Old 05-23-2010, 09:25 PM
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Why is that a bad assumption? Regardless of all the technalities placing the new sub in the same position should result in the same room and placement effects shouldn't it? And if so why not?


Thanks Pete but as I said I can't place it there. Is that my best or only option?
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Old 05-23-2010, 10:05 PM
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So you can place the sub on the right hand side of the DVD rack, but not the left hand side, is that correct?

You may as well try the other 2 placement positions that you have available, but I'm not sure if they will be any better than the first position.

In a room such as this with relatively small dimensions all around, it is difficult to get a smooth overall bass response with a single true subwoofer.

Are you mainly looking for more mid/upper bass punch? If so, then you can always add an MBM-12 MK2. Place it on it's side with woofer firing forward running in 'Sealed' mode, and place the ULS directly on top of the MBM (so that both drivers are firing forward).

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Old 05-23-2010, 10:29 PM
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Why is that a bad assumption?

Different subs have different acoustic characteristics, and will interact with your room acoustics in different ways. The only way to achieve the best performance for your new sub is to experiment with different placements to find the one that best integrates it into your room.

And, of course, a lot depends on how you define "impactful". Volume alone is not a measure of whether one sub is better than another. A higher quality sub, when placed in the proper position, should result in smoother bass response with lower distortion. That does not necessarily mean louder.
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Old 05-24-2010, 07:31 AM
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So I was thinking and I really don't want to move the sub to the corner that Pete has recommended because a lot of dust gathers in that corner. If I want to can I up the volume on the sub itself to 12 o'clock or raise the volume in the receiver 3 dB? Would it be ok if I run it this hot? Pete I mean no disrespect by disregarding your suggestion but it is nbecause I rather preserve my sub than destroy it. I am thinking I should add another ULS for the kind of bass I want. Pete I am really looking to get an extreme slam on the mid bass section and a good rumble low down. Nothing extreme like a paradigm sub25 but good enough. I hAve the ULS paired with some Paradigm Signature S4 and they are pretty decent speakers.
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Old 05-24-2010, 07:47 AM
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If you have an SPL meter, pick up a couple cables and get REW (free), run some measurements to see if you have some bad nulls or peaks causing issues.
Or download a bunch of tones (say from 15hz to 100 in 5 hz increments, and measure the response using a spreadsheet and your digital SPL meter (there are correction values to be applied to the Radio Shack Meter if that is what you are using).

 

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Old 05-24-2010, 07:58 AM
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does it make a difference if the sub is on the metal feet or on the ground?
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Old 05-24-2010, 09:55 AM
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does it make a difference if the sub is on the metal feet or on the ground?

It really doesn't make much of a difference.

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