Turbo Revolution?

[PeterB]

Greetings

Can someone please explain how the HO turbo works and why it should be considered revolutionary? Seems to me it just lowers the Fb and possibly reduces the port air velocity. If this performance 'free lunch' is so readily available why aren't all subwoofers simply designed with huge slot ports? Am I missing something?

:confused:

[RatFarm]

"Turbocharger doubles the port cross-sectional area in extended bass mode vs. plugging one port with a port plug. This means that the air now has double the amount of space to move through, which reduces air velocity and leads to much less port turbulence-related noise and much less output compression near port tuning.
__________________
Peter Marcks
Hsu Research "

[PeterB]

Peter

OK. I am aware of the relation between port length/box volume/port cross-sectional area. It's just a Helmholtz resonator - this is all very old physics. So the turbo is nothing more than a big port? Hardly a new concept: bigger port = lower air velocity = less chuffing. So why not just design it with the big port in the first place?? It certainly would look better. ;>)

PS Rat Farm???

[craigsub]

Peter

OK. I am aware of the relation between port length/box volume/port cross-sectional area. It's just a Helmholtz resonator - this is all very old physics. So the turbo is nothing more than a big port? Hardly a new concept: bigger port = lower air velocity = less chuffing. So why not just design it with the big port in the first place?? It certainly would look better. ;>)

PS Rat Farm???


It would require a much larger enclosure to have the ports installed internally, as you suggest. Of course, as you are an expert in old Physics, you already knew this ... :D

The turbo concept allows for the consumer to make a choice, in regards to performance, while keeping production costs lower.

[SeattleDucks]

Greetings

Can someone please explain how the HO turbo works and why it should be considered revolutionary? Seems to me it just lowers the Fb and possibly reduces the port air velocity. If this performance 'free lunch' is so readily available why aren't all subwoofers simply designed with huge slot ports? Am I missing something?

:confused:


Peter

OK. I am aware of the relation between port length/box volume/port cross-sectional area. It's just a Helmholtz resonator - this is all very old physics. So the turbo is nothing more than a big port? Hardly a new concept: bigger port = lower air velocity = less chuffing. So why not just design it with the big port in the first place?? It certainly would look better. ;>)

PS Rat Farm???


With your obvious subwoofer design/physics knowledge, you certainly already knew the answer to your own question, so why even post it?

It's interesting how HSU is becoming a bigger forum target now with the recent successes of their new lineup...it is my suspicion that several recent postings (such as the "made in China" thread) are planted here by certain entities for a purpose - to place a seed of doubt in the minds of potential new HSU customers :eek:

But the proof is in the actual listening, where myself and many others are preferring the extremely musical sound and high performance of our new HSU subs over competitors in the same price range :D

[lradden]

With your obvious subwoofer design/physics knowledge, you certainly already knew the answer to your own question, so why even post it?

It's interesting how HSU is becoming a bigger forum target now with their recent successes...it is my suspicion that several recent threads (such as the "made in China" crap) are planted here for a purpose :eek:Well stated Seattle. We're going to see more and more individuals with 1 or 2 post now that Hsu is just plain kicking butt in sales due to the new lineup. Let's face it sales are up for Hsu and down for the competition so yes it is my opinion that the competition has individuals coming here to post these kind of questions and try to put doubt in the minds of true potential customers. Why else do you think all these sub experts are suddenly showing up on Hsu and AVS with 1 post. Do you really think that Hsu put out a new lineup that is putting a big dent in the competitions sales and all of a sudden the sub experts suddenly discovered the AVS and Hsu forums. These guys have been around a long time under different names and are now posting under new Ids to try and raise doubt in Hsu. Nice try guys, but the superior product is finally getting it's just rewards. Too bad the Dr. has patents now isn't it.

[Pete_Hsu]

Ease up, guys. PeterB's questions are perfectly valid, if a bit blunt and direct :)

Peter, I would consider the turbocharger to be evolutionary design. I don't believe we've ever stated it as being revolutionary. It is an evolution of our variable tuning technology that debuted with the VTF-2.

So, what's the point of all this? The point is being able to offer a different approach towards variable tuning, one that does not sacrifice precious port cross-sectional area, one that does not compromise floorspace or base enclosure size, and one that is modular (meaning that it can be added at any time in the future). Note that the enclosure size needed to house dual 4" ports tuned to 16Hz would be quite huge in comparison to the VTF-3 Mk3/HO base enclosure.

I hope this clarifies things a bit...

[lradden]

Peter, I apologize for being so blunt, but things like this have been going on lately. There have even been post over on AVS from someone who calls himself sjmarcy who has been questioning Craigsubs testing only because his testing is showing Hsu subs to be better performers. Now that individual has been exposed
as having along time relationship with another company and has been warned by the moderator to watch it. www.avsforum.com/avs-vb/showthread.php?p=9542985&&#post9542985 It's becoming more and more obvious that a competitor of yours is trying to raise doubt about your products by means other than advertising.

[PeterB]

Guys, I'm not a company shill for SVS or anybody else! In fact I am a HSU customer. So lets try to keep the paranoia in check, ditch the personal attacks and just stick to the subject.

SeattleDucks/Iradden: I really didn't know the answer to my post - I thought maybe the turbo did have some additional integration with sub I was unaware of. And by the way... why shouldn't anyone be allowed to post contrary views? You certainly are free to post your partisan opinions - why not just address the facts and use knowledge and persuasion to make your case?

[JonnyOzero3]

We're all friends here, no worries. You are allowed to post contrary views - things are just getting touchy as there have been some pretty rude and harsh words lately. So, let's all ease up....

It's a valid question - I mean...of course the answer is "build a bigger box." But then you think...ugh, "build a bigger box?"

This is an elegant solution to a common tradeoff in sub design, me thinks. It puts the power of decision in the hands of the consumer. As a consumer, I love having options.

[Stan]

Peter, I apologize for being so blunt, but things like this have been going on lately. There have even been post over on AVS from someone who calls himself sjmarcy who has been questioning Craigsubs testing only because his testing is showing Hsu subs to be better performers. Now that individual has been exposed
as having along time relationship with another company and has been warned by the moderator to watch it. www.avsforum.com/avs-vb/showthread.php?p=9542985&&#post9542985 It's becoming more and more obvious that a competitor of yours is trying to raise doubt about your products by means other than advertising.

This is a shoot the messenger sort of situation I think. Me being the messenger. I am sjmarcy@aol.com. You are misinforming people about me, please cease this activity. It does not need to be handled in a character assasination / cover up type of manner. I know many people in the industry, it happens over time. I'm sure you know a few too. I post on my own, my own words and opinions, etc. I do not speak for SVS. So what?

My concerns about Craigsub's tests have nothing AT ALL to do with brands. Good test procedures help avoid situations such as this one and are in everyone's best interest. Including subwoofer companies.

Craig sub stated that a particular sub had 14.5 to 18.5 dB lesser output @45 Hz than a close competitor which happened to be a Hsu unit. The *extremely* low output sub was an SVS. I have no control over what sub performs like that, H or S. But if you know subs, you'll agree that a monumental output difference such as that one merits further investigation. It is a huge and inadequately explained difference. Craigsub NOW states that this was due to the limiter which "collapsed" the output when the sub was overdriven. With the amount of output drop Craig confirms, nearly ANY brand of sub will have more output in this situation. It has nothing to do with other subs, it has to do with that sub and the test/rating process.

The thing is...if you question Craigsub....it seems to lead to attacks and not answers. Lets try to get to the latter. There seems to be a love / hate thing at AVS regarding these two companies. I did not realize this as I have not been active on the various forums in years. I have been an AVS member since the late 90s. My screen name (probably Stan or close) dropped off for inactivity so I needed to re-register. I have asked that they research the matter and one of the moderators for that time period vouches for me.

The amount of output drop in question is highly suspect. Limiters don't normally do this. Usually the sub just stops getting louder at some point, sometimes output eases off very slightly like a dB or so. Suppose a sub is nearly at it's limit when hitting 100 dB SPL @ 45 Hz. Add 3 more dB input and suddenly the sub now puts out somewhere in the 80s dB? That is awful if true. Subjectively that is like turning the sub off. Yeah. That is what Craigsub claims for a sub whose brand seems to be one he has had long term problems with and was apparently associated with him getting banned from one or more forums. Craigsub's response to my pointed question glosses over this new issue. The issue remains open.

Either the sub in question is broken, an awful design, or there were measurement / test issues = likely scenarios. I'd like to see the matter looked into in a credible manner. Again that is in everyone's interest including Hsu Subs. Else next week some other weird thing will come up in such tests and who knows what the brands will be at that time. The tests should be more credibily performed and there should be more openness towards discussing such matters is my view. Some in the thread feel that Craigsub's tests/ratings are really more or less subjective opinions (fine) but with shakey objective testing (not fine). If the objective tests are not up to snuff right now, fine, tune them up or drop them.

So...let's find out what happened and not get emotional and attack me.

[Ddavidson]

This is a shoot the messenger sort of situation I think. Me being the messenger. I am sjmarcy@aol.com. You are misinforming people about me, please cease this activity. It does not need to be handled in a character assasination / cover up type of manner. I know many people in the industry, it happens over time. I'm sure you know a few too. I post on my own, my own words and opinions, etc. I do not speak for SVS. So what?



Mr Marcy I think I speak for the vast majority of Hsu owners that use this forum ..... this is Hsu Research's private product support forum ... so such political bum fights are not appropriate to be posted here. That BS is best left to public forums which discuss a large variety of brands and issues.

As a long time friend and supporter of TV's you are better to discuss that via PMs with both lradden and Craigsub (or even on AVS or the SVS forum (HTF). Perhaps even email your concerns to Mr Ed Mullins the SVS product spokesperson (reviewer for Secrets) as he is well versed over the past few years in presenting graphs and numbers for his SVS reviews.

I doubt anyone here would want to pollute this forum with the politics of people who have conflicting interests or other brand biases.

You could say as Hsu owners we reserve the right to be very biased on this forum because we choose Hsu over any of the other options on the market. But go right ahead and "say what you want" on the public a/v forums.

Ddavidson

[AudiblConoiseur]

Stan,

I am not a long time forum go'er but I can tell you that I have never seen this on this forum before. I do not speak for any particular person on this forum although I will most likley have many that agree with me. If not, then please disregard (respect, HSU-crew :) ).

True, it is a HSU forum but then we all find a way to agree or disagree but we can agree to disagree none-the-less. While we as people can appreciate your opinions and respect the fact that you are trying to 'uncover' facts and protect your entity, this is not the place for it. If you are right, you are right. If you are wrong, it will come out in the wash. All that is b/t you and the persons involved. No one at this forum seems to be involved in this issue until now. With respect, please cease from posting further information about this issue at the HSU forum and take it back to AVS or wherever it originated and if needed, get it moderated by someone at the AVS forum to help bring it to a close. Doing this the way you are is making yourself out to be the bad guy if you are not and a spy/troll if you are. Good luck with the issue but please don't continue your personal or protective agenda here, it is inappropriate!

[mystro]

AudiblConoiseur, just my opinion, I find those with 1 thousand postings and above in this forum fishy, except for Peter Marcks, the others might have an agenda. :eek: This being a new forum you know, the rest is up to you to figure out. :rolleyes:

[Ddavidson]

AudiblConoiseur, just my opinion, I find those with 1 thousand postings and above in this forum fishy, except for Peter Marcks, the others might have an agenda. :eek: This being a new forum you know, the rest is up to you to figure out. :rolleyes:
Remember this forum is a support forum and it is "not new". In fact it is nearly 4 years old (for post counts).
I always had hoped for a dedicated forum for Hsu owners as my first Hsu sub was purchased way back in 1995. At one time or another I have had every Hsu model since then .... so Hsu designs are definitely not a new part of my system.

http://forum.hsuresearch.com/showthread.php?t=1

Ddavidson

[wid]

I bet there are a lot of folks on here now that don't know who Sasha is. I've been around a while and Mr. Ddavidson was here when I showed up. He is also a very knowledgeable and well respected member of the Hsu forum.

[BradJudy]

This is sad - paranoid shill-tagging responses are making this forum go downhill and I visit this place much less these days.

I'm glad that the forum owners have been more open in the past year or two regarding discussion that includes competitors (back in the day, it was explicitly prohibited), but the forum members have largely degraded the interesting discussions.

As a long standing member of numerous audio forums who has been tagged as a shill (for a variety of vendors on a variety of forums), I'm sorry to see this happen.

[mystro]

I bet there are a lot of folks on here now that don't know who Sasha is. I've been around a while and Mr. Ddavidson was here when I showed up. He is also a very knowledgeable and well respected member of the Hsu forum.

eh.., with 1 thousand posting who won't respect? :D :D

Sasha, I read a couples of his past posting, while searching for some information on Hsu's sub. Before Peter Marcks right :confused:

Any way, Mr. Ddavidson thanks for clarifications. :p

[Ddavidson]

Before Peter Marcks right
Yes Sasha used to run Blue Whale Audio and joined Hsu before going back to do more studies. A good "genuine guy" who created the web site/forum (old and new).

I'm glad that the forum owners have been more open in the past year or two regarding discussion that includes competitors (back in the day, it was explicitly prohibited),
Brad nothing wrong with discussion and direct comparisons to Hsu's competition. I am sure everyone here welcomes such genuine discussions. However as can be seen by people with obvious agendas (like mountsalami, sjmacey) these are not genuine "potential" Hsu buyers, they are here to engage in political muck racking which is best left on forums that are designed for such subjects. YMMV but IMHO Hsu should not have to give bandwidth to people with such obvious agendas.

Genuine discussion on our hobby should always be welcome.

Ddavidson

[SeattleDucks]

Mr Marcy I think I speak for the vast majority of Hsu owners that use this forum ..... this is Hsu Research's private product support forum ... so such political bum fights are not appropriate to be posted here. That BS is best left to public forums which discuss a large variety of brands and issues.

As a long time friend and supporter of TV's you are better to discuss that via PMs with both lradden and Craigsub (or even on AVS or the SVS forum (HTF). Perhaps even email your concerns to Mr Ed Mullins the SVS product spokesperson (reviewer for Secrets) as he is well versed over the past few years in presenting graphs and numbers for his SVS reviews.

I doubt anyone here would want to pollute this forum with the politics of people who have conflicting interests or other brand biases.

You could say as Hsu owners we reserve the right to be very biased on this forum because we choose Hsu over any of the other options on the market. But go right ahead and "say what you want" on the public a/v forums.

Ddavidson

FULLY AGREE!!!

[craigsub]

This is a shoot the messenger sort of situation I think. Me being the messenger. I am sjmarcy@aol.com. You are misinforming people about me, please cease this activity. It does not need to be handled in a character assasination / cover up type of manner. I know many people in the industry, it happens over time. I'm sure you know a few too. I post on my own, my own words and opinions, etc. I do not speak for SVS. So what?

My concerns about Craigsub's tests have nothing AT ALL to do with brands. Good test procedures help avoid situations such as this one and are in everyone's best interest. Including subwoofer companies.

Craig sub stated that a particular sub had 14.5 to 18.5 dB lesser output @45 Hz than a close competitor which happened to be a Hsu unit. The *extremely* low output sub was an SVS. I have no control over what sub performs like that, H or S. But if you know subs, you'll agree that a monumental output difference such as that one merits further investigation. It is a huge and inadequately explained difference. Craigsub NOW states that this was due to the limiter which "collapsed" the output when the sub was overdriven. With the amount of output drop Craig confirms, nearly ANY brand of sub will have more output in this situation. It has nothing to do with other subs, it has to do with that sub and the test/rating process.

The thing is...if you question Craigsub....it seems to lead to attacks and not answers. Lets try to get to the latter. There seems to be a love / hate thing at AVS regarding these two companies. I did not realize this as I have not been active on the various forums in years. I have been an AVS member since the late 90s. My screen name (probably Stan or close) dropped off for inactivity so I needed to re-register. I have asked that they research the matter and one of the moderators for that time period vouches for me.

The amount of output drop in question is highly suspect. Limiters don't normally do this. Usually the sub just stops getting louder at some point, sometimes output eases off very slightly like a dB or so. Suppose a sub is nearly at it's limit when hitting 100 dB SPL @ 45 Hz. Add 3 more dB input and suddenly the sub now puts out somewhere in the 80s dB? That is awful if true. Subjectively that is like turning the sub off. Yeah. That is what Craigsub claims for a sub whose brand seems to be one he has had long term problems with and was apparently associated with him getting banned from one or more forums. Craigsub's response to my pointed question glosses over this new issue. The issue remains open.

Either the sub in question is broken, an awful design, or there were measurement / test issues = likely scenarios. I'd like to see the matter looked into in a credible manner. Again that is in everyone's interest including Hsu Subs. Else next week some other weird thing will come up in such tests and who knows what the brands will be at that time. The tests should be more credibily performed and there should be more openness towards discussing such matters is my view. Some in the thread feel that Craigsub's tests/ratings are really more or less subjective opinions (fine) but with shakey objective testing (not fine). If the objective tests are not up to snuff right now, fine, tune them up or drop them.

So...let's find out what happened and not get emotional and attack me.

Stan ... I see you are now resorting to the attacks across other forums.

Let us set the facts straight.

1. I was banned from Home Theater SPot because Tom V. was making fun of his competition as "being afraid of having an Ed Mullen style test done" ... and all I said to him was that making fun of one's competition was not very gentlemanly... I still believe that. It is nothing personal, as you suggest. Bad behavior is bad behavior. Period. As I don't like this type of trash talk in any forum, if you go look, I was pretty clear in stating that I did not believe Ron or Tom "put you up" to this tirade of yours. In other words, Stan, I once again defended a manufacturer who was being attacked, just as I did on Home Theater SPot. Only this time the manufacturer was SVS.

2. You are welcome to come here and see my set up for yourself - the PB12-NSD will repeatedly exhibit the same collapse @ 45 Hz while trying to deliver beyond its limits at 20 Hz. I posted both graphs, and the graph with the PB12 running under its SPL limit at 20 Hz did not show this 14-18 dB lower SPL @ 45 Hz. Once again, you ignored the entire body of work in order to nit pick about one graph which you did not like. What you are not understanding is the dynamic nature of the test material. This was not a case of applying a 45 Hz sine wave, increasing that by 3 dB, and seeing an 18 dB drop, as you assert here. It was during a very taxing movie scene.

And Stan, let's stop with the prevarications, shall we ? I never stated that the PB12 was 14-18 dB lower in SPL @ 45 Hz. A graph taken using some very good equipment showed this as a measurement. Rather than use this to denigrate the SVS sub, as you want to think I do because of some agenda, I ran the test again, but looked for the onset of compression ... and stopped there. What happened ? The SVS delivered appx. 14 dB higher SPL (or about 103 dB total) @ 45 Hz, as I thought it would.

3. You were asked on several occasions to post WHAT your concerns are. Your answer is never to answer. You would rather complain incessantly, and post anonymous "concerned PM's" from some so-called "other members of the forum".

4. Finally, no one attacked you. They were dismayed by your lack of intellectual honesty. I offered to participate in a new thread about how the testing was done, so we could discuss this like gentlemen. You, of course, refused that offer. The offer still stands.

[SeattleDucks]

Stan ... I see you are now resorting to the attacks across other forums.

Let us set the facts straight.

1. I was banned from Home Theater SPot because Tom V. was making fun of his competition as "being afraid of having an Ed Mullen style test done" ... and all I said to him was that making fun of one's competition was not very gentlemanly... I still believe that. It is nothing personal, as you suggest. Bad behavior is bad behavior. Period. As I don't like this type of trash talk in any forum, if you go look, I was pretty clear in stating that I did not believe Ron or Tom "put you up" to this tirade of yours. In other words, Stan, I once again defended a manufacturer who was being attacked, just as I did on Home Theater SPot. Only this time the manufacturer was SVS.

2. You are welcome to come here and see my set up for yourself - the PB12-NSD will repeatedly exhibit the same collapse @ 45 Hz while trying to deliver beyond its limits at 20 Hz. I posted both graphs, and the graph with the PB12 running under its SPL limit at 20 Hz did not show this 14-18 dB lower SPL @ 45 Hz. Once again, you ignored the entire body of work in order to nit pick about one graph which you did not like. What you are not understanding is the dynamic nature of the test material. This was not a case of applying a 45 Hz sine wave, increasing that by 3 dB, and seeing an 18 dB drop, as you assert here. It was during a very taxing movie scene.

And Stan, let's stop with the prevarications, shall we ? I never stated that the PB12 was 14-18 dB lower in SPL @ 45 Hz. A graph taken using some very good equipment showed this as a measurement. Rather than use this to denigrate the SVS sub, as you want to think I do because of some agenda, I ran the test again, but looked for the onset of compression ... and stopped there. What happened ? The SVS delivered appx. 103 dB higher SPL @ 45 Hz, as I thought it would.

3. You were asked on several occasions to post WHAT your concerns are. Your answer is never to answer. You would rather complain incessantly, and post anonymous "concerned PM's" from some so-called "other members of the forum".

4. Finally, no one attacked you. They were dismayed by your lack of intellectual honesty. I offered to participate in a new thread about how the testing was done, so we could discuss this like gentlemen. You, of course, refused that offer. The offer still stands.

Craig, your response here is intelligent, factual, and far more civil than I would have been at this point had I been in your shoes. Unfortunately, I'm afraid the truth will be lost on a guy like Stan "sjmarcy" based on his recent posting history. But maybe he will prove me wrong and suddenly become reasonable in the way he thinks and communicates.

[Mozvz]

Stan,

I generally do not get involved with the heated discussions on these forums. However, in my life's experience, (I am no spring chicken) there generally is a common sense approach to resolving conflict.

In my opinion, the best way around this is to begin a thread that YOU initiate with your methodology for testing purposes.

This hopefully would begin the process of you being able to present your views and then have people critique and provide feedback. Ideally the discussion would be respectful, robust and proactive. You have been perceived by many as a "troll/troublemaker." I have yet to form an opinion at this point in time as perception many times is not valid.

I do not know you personally, but I sense you are extremely intelligent, well versed and have a wealth of experience to share. This knowledge is what these forums are about and it does not need to be done in a negative manner.

I respectfully ask you to begin your OWN thread and take the time to present your views. I am sure you have much to share and we could all learn from your experience because that is the true meaning of why we are all here.

[Macfan424]

It's sad that this has escalated as it has. I've been lurking in both forums and finally feel the desire to comment.

Stan is an experienced, well qualified, respected member of the audio community, but somehow he seems to fail to understand what Craig (craigsub) is doing.

Instead of accepting that Craig is a hobbyist (like most of the rest of us), who happens to be willing and able to devote significant financial and temporal resources to testing and comparing subs, Stan seems to see him as a professional reviewer and/or a protagonist for one firm. In fact, Craig didn't even open the thread that Stan (sjmarcy) responded to initially and has no financial interest in his rankings.

My observation is that Craig behaves like a gentleman and bends over backwards to try to be fair. If someone points out how his data can be misinterpreted, he attempts to clarify.

Stan's concerns would be legitimate if directed at someone who posed as a professional proffering buying advice, but Craig does not. Stan attacks Craig's testing methods as if they varied from some accepted standard, although he is fully aware there is no one "right" way to measure sub performance, only some that are less flawed than others. He inappropriately blames Craig for conclusions drawn by other forum members.

While Craig generally responds to these challenges politely, often his defenders do not. Before long, no one is listening, only shouting.

I have reservations about some of Craig's approaches, too, as I do about all reviews. I'm especially concerned about how his attempt to put numerical scores on at least partially subjective observations results in many readers (mis)interpreting them as hard objective facts.

Nonetheless, I applaud his efforts, respect his findings and hope he continues to share them with us.

I also agree with the notion this debate has no place here, but Stan didn't open it. He just responded when someone else did. In any case, everyone should heed Rodney King's advice.

FWIW, I'm a proud owner of both Hsu and SVS subs, and find both to be fine companies that offer excellent, high value products. ;)