HSU VTF-15H Subwoofer Review

[GranteedEV]

The fact that it isn't as good as much more expensive subwoofers should not surprise anyone. It would be ridiculous to expect that it would be the best subwoofer ever made, given how much more some subwoofers cost.

I imagine the subwoofer won't cure cancer or fill out one's tax forms either, and now some damn fool may imagine that in saying that, I am slamming the subwoofer.

Don't let people upset you when they demonstrate a lack of reading skills and crazy ideas of what can be done at some price point.

Exactly.

You want it to get loud, you have to have displacement, either by excursion, surface area, or both.
You want it to sound good with a huge cone, you need a very controlled motor designed for that cone.
You want it to dig deep, you have to add mass.
You want it to dig deep WHILE being loud AND sounding good you need all of the above at the same time.
You do the above, and all of a sudden you've lost sensitivity and you need a ton of amplification to get it loud.
You add a ton fo amplification and now you need to compensate for the extra generated heat somehow.
You do the above, you still need to keep the driver under control. So you need a very linear motor or servo control.
You do the above, you still need a box that will damp the driver well while producing the right balance of output and extention for the driver in question. "Small, Loud, and Low, Pick Two, you'll never get the other"
You do all above, now you need to focus on keeping the driver within its physical limitations within that box so that it doesn't bottom out.
You do the above and you've "theoretically" sacrificed sound quality.
You do all the above and you still need to factor in the room, where nodes and modes are omnipresent. So you need not one, but three or four subs!
You do the above, and you still need to measure and EQ it to get the desired response at the seating positions.
You finally do all of the above, and you're sitting at a LOT of money spent on subwoofers. That's the iron rule.

In my mind's eye the "ultimate bass experience" would be

About 8-10 huge linear pro audio drivers (TC Sounds LMS-5100, $800 each) in two line array (floor to ceiling) dipoles (which means more power to EQ/compensate for a 6db/octave rolloff which starts well above the usual passband of any sub) well out from any boundaries
+ EQs to do the above transfer function shaping
+ so much amplification I cannot imagine to do the above EQing properly. Preferably Class D.
+ circuit breakers and house wiring to actually deal with that intense amplification
+ One or Two rotary woofers, at about $13,000 a pop to take care of the low end that the above woofers won't be able to
+ welll implemented crossover between the two sets of woofers.

Just calculate the cost of that.

For $800 the HSU is a great value. Anyone expecting a world beater sub for under $1000 is out of their mind. Especially since we're talkin about a single sub. Get two, add some corner bass traps and I don't think you could do better for $2000 no matter how you spend your money. (besides DIY lol).

The idea that the HSU is mediocre is confounding to me. As a single sub relative to more expensive world-class subs perhaps. But I garuntee it outperforms the majority of subs below $2000 overall. There's exceptions, but those are exceptional subs.

 

[sharkman]

I think you worry too much about negative reactions to reviews. One might hope that "As a reader, I'd hope people could figure that out without it having to be spelled out to them", but that is but a hope. Anyone who imagines the review was trashing the subwoofer needs to learn to read. Here are some choice quotes for them:

Weighing in at 123lbs and costing $879 for the black finish, it was hands down, the “BEST BUY” of the group of subs we compared. HSU demonstrated strong engineering, excellent integration of the sub with the power amp and cabinet, and a surprising amount of output from the system given the relatively low output capacity of the amplifier used. The VTF-15H is an excellent example of what can be done when you attempt to squeeze the last bit of performance from a modest budget.​

http://www.audioholics.com/reviews/speakers/subwoofers/vtf-15h

Frankly, for a subwoofer, as long as the cone won't break from the stress of forces, anything commonly used if made of a sufficient thickness (which for different materials means a different mass of course) is going to be pistonic, a term meaning it will act like an air pump, and simply push and pull the air alternately setting up those low frequency waves we enjoy so much. Even paper is hard enough to be acting like a simple piston (what you want) at subwoofer frequencies.​

http://www.audioholics.com/reviews/speakers/subwoofers/vtf-15h/vtf-15h-introduction

In other words, there is nothing wrong with using paper for the cone material, so people who are upset that the review said it was paper really need to pay more attention. Plus, of course, are they unable to see that it is paper when they look at it, so they are offended when someone tells them what it is? Really, people being upset by this is ridiculous.

As an engineer whose entire career has rested on product development, and having designed dozens if not hundreds of powered subwoofers since the late 80's, I can say without reservation the Hsu Research is an excellent effort on a shoestring budget.​

http://www.audioholics.com/reviews/speakers/subwoofers/vtf-15h/vtf-15h-conclusion

everyone looking for a bargain, anyone in the market for a $900 to $1000 subwoofer would be foolish to not consider the Hsu Research VTF-15H. It is an excellent example of what can be done when you attempt to squeeze the last bit of performance from a modest budget.​

http://www.audioholics.com/reviews/speakers/subwoofers/vtf-15h/vtf-15h-conclusion

If anyone imagines the review is trashing the subwoofer when it said that it is the best subwoofer tested at its price point, really must have very poor reading skills.

The fact that it isn't as good as much more expensive subwoofers should not surprise anyone. It would be ridiculous to expect that it would be the best subwoofer ever made, given how much more some subwoofers cost.

I imagine the subwoofer won't cure cancer or fill out one's tax forms either, and now some damn fool may imagine that in saying that, I am slamming the subwoofer.

Don't let people upset you when they demonstrate a lack of reading skills and crazy ideas of what can be done at some price point.

Interesting thoughts, it seems that damn fools are afoot!

First of all, a reviewer can say and do whatever they prefer when putting a product through it's paces, but I think the main bone of contention in this thread is that the VTF-15 was only tested in one mode (which is best for mid bass only) when it is designed to be tuned and adjusted for various modes. It was never tested in max extension mode, and then criticized for having little bass below 25Hz. It has more output but we will never know what it is by reading this review. As it is it achieved only about 4.5 db less than the SVS PB12-Plus sub at 20 Hz. If it had been tuned for max extension, who knows how it might have done.

As for the paper cone, my point, for one, was that this was nitpicking(although it was mentioned that paper will burn when overheated - a strange thing to say), along with the feel of the volume knob, the weight, and the crossover range. Only by digging into the manual, which I downloaded, was I able to determine that the review was missing essential info about the crossover. You can hit a switch thus defeating the sub crossover and allowing the AVR to control the crossover point. So the sub is not limited at all by a 30 - 90 Hz range.

 

[clouso]

reading and reading everywhere and i am beleiving now that this subwoofer has not been tested to its full capabilities and also....in that matter if that sub offers more flexibilities then the others then be it and it should have been tested!...2 cents....

 

[Ron Temple]

All of the subs tested so far have variable tuning options. Each was tested as is. The test is fair, the results vary, but in each review Paul explains why each sub measures the way it does in vanilla mode. Had he gone in depth about each tuning option, there would be more data, but he explained the likely outcomes. There have been nitpicks about each sub that can easily be dismissed. The telling difference in the Hsu product that stood out to me was the amp and it's limitations in comparison to the more robust SVS and Rythmik products. The amp is not a weakness, it's a design choice and I'm sure it's absolutely the best 350w variable tune amp available at it's pricepoint.

 

[kevon27]

Question. Why is so important to have sub play below 20hz?

Do subs in movie theaters even go below 25hz?

 

[GranteedEV]

reading and reading everywhere and i am beleiving now that this subwoofer has not been tested to its full capabilities and also....in that matter if that sub offers more flexibilities then the others then be it and it should have been tested!...2 cents....

Well the main goal of the subwoofer shootout is to compare output/distortion. While lower tuning modes give more extention, output is what people perceive in most movies.

20hz extention mode will have less output in the ~30hz region but more in the ~20hz region, and likely sound a bit better in most rooms anyways. Keep in mind that 20hz is a barely audible frequency so you're trading more audible frequencies for less audible frequencies plain and simple. Of course IMO FR should be flat in room, not house curved in any way.

Remember that Brian of rythmik was commenting on how Illkka's tests of the FV12 or whatever it was were done in max extention mode and made the sub look compressed and weak. Everything is a tradeoff. Paul chose to use the high output modes to give these subs the best numbers around 30hz and above instead of focusing on 20hz. I would have appreciated more listening done in the other port tuning modes but I guess he had to stay consistent for the "shootout".

Question. Why is so important to have sub play below 20hz?

Do subs in movie theaters even go below 25hz?

Some movies have content down there, although movie theater subs usually don't extend below 30hz or so.... Reference movies like Iron Man 2, Inception, War of the Worlds, for example do have some serious infrasonic or low bass content that really taxes subs and so we want the perfect sub to do them justice but sometimes it's a ridiculous goal.

Remember, most people's "subwoofers" don't even extend down to 35hz properly, and are actually amplifier limited and one-notey. Us crazy people are just greedy

 

[kevon27]

Remember, most people's "subwoofers" don't even extend down to 35hz properly, and are actually amplifier limited and one-notey. Us crazy people are just greedy [/QUOTE]

Yes, we are... I'm proud to be a glutinous American.. Give me my 7hz @130db subwoofers.

 

[GranteedEV]

Yes, we are... I'm proud to be a glutinous American.. Give me my 7hz @130db subwoofers.

nah. Extention down to 12hz is all you need. Our body can't much perceive frequencies below that. Our ears can't even go below 20-22hz. And anything over a clean 115db at seating position is overkill as you'd be watching movies louder than reference levels which is not only going to sound harsh but also damage your ears/body. And you'll likely never need that type of output/extention for any kind of music.

 

[KEW]

If anyone imagines the review is trashing the subwoofer when it said that it is the best subwoofer tested at its price point

I agree with your main point, but did the review say it is the "best subwoofer tested at its price point"? I missed that!

That is a much stronger statement than saying:

anyone in the market for a $900 to $1000 subwoofer would be foolish to not consider the Hsu Research VTF-15H.

 

[Pyrrho]

Question. Why is so important to have sub play below 20hz?

Do subs in movie theaters even go below 25hz?

In most cases, it isn't important. Most music does not go that low, though the lowest possible note on a pipe organ does (of course, most people do not listen to such music, so that is irrelevant to them).

It is sometimes used in sound effects in movies, though with that, giving one a good thump down to about 25 Hz will probably seem totally fine, as long as one never compares with a subwoofer that goes deeper (as they may feel different).

As for movie theaters, I would be surprised if very many are capable of a decent output below 25 Hz, as they need to fill a huge room with sound, so in the compromise between volume and depth of bass, they would be foolish to sacrifice volume for that. Of course, with enough woofers, it would be possible, but movie theaters are made for making a profit, and it would cost a lot to get really deep bass in a huge theater at the volumes required. That, however, is not a reason to have the same sound in your home. You can get better sound in your home, as movie theaters have to pick speakers capable of playing at tremendous volumes that are unnecessary in a normal room in one's home.

So, if one has the money, then I think getting something that can play loud and deep is a good idea. But we are talking about more money than what Hsu is asking for this subwoofer.

 

[Pyrrho]

I agree with your main point, but did the review say it is the "best subwoofer tested at its price point"? I missed that!

That is a much stronger statement than saying:

Weighing in at 123lbs and costing $879 for the black finish, it was hands down, the “BEST BUY” of the group of subs we compared.​

http://www.audioholics.com/reviews/speakers/subwoofers/vtf-15h

And also quoted in my post to which you responded:

http://forums.audioholics.com/forums/showpost.php?p=788862&postcount=59

If it is not the best subwoofer (of those they tested) at its price point, how could it possibly be the "BEST BUY"? If there is a better subwoofer at its price point that they tested, then that other subwoofer would be a better buy, and consequently the Hsu would not be the best buy.

Really, the review is quite positive. It just isn't the best subwoofer ever made at any price.


Some people were wanting this $879 subwoofer to be better than the SVS PB12-Plus that costs $1399. If the SVS were not better, the SVS would be a crappy buy, as it costs over $500 more for it; a greater than 50% increase in cost. That extra little bit of depth to the bass is not cheap. And if you wanted to go another few hertz lower than that SVS, it would cost more. Basically, each additional 5 Hz of depth is going to cost more than the previous 5 Hz of depth; it is expensive to get really deep bass, and instead of cheating you out of a good volume, Hsu has allowed the really deep bass to fall off some. But lower than most people really require.

Probably, the Hsu VTF-15H is not only better than what most people ever buy, it is probably as good as most people would ever feel the need to have.

 

[Sputter]

Nowhere in this review does it say the HSU sub is NOT recommended for Hometheater usage.

Here is Paul's direct quote:

This box (in my opinion) is best for music, and while it will work for home theater, if you absolutely have to get that 20 Hz tone in your living room, be prepared to spend more $$ and get a system with a bigger amplifier, or do as Dr Hsu recommends and place the box in the room corner if at all possible. Perhaps HSU will consider offering a hot rod version of this product (bigger amp, bigger driver motor) at a slight cost adder to those bass heads really wanting uncompromised true 20Hz extension.

He's wrong in his assesment, don't have to spend more $$. Plug one port and you get sub 20hz easily.

 

[emorphien]

Question. Why is so important to have sub play below 20hz?

Do subs in movie theaters even go below 25hz?

Based on my experiences in most theaters,even some nicer IMAX systems, etc, I'd say they struggle to even hit 25Hz and they're probably fading fast at 30Hz.

They are more concerned about getting enough of the visceral slam and volume but getting true extension in a theater that size is extremely difficult and expensive.

 

[kevon27]

He's wrong in his assesment, don't have to spend more $$. Plug one port and you get sub 20hz easily.

If you plug on port wouldn't that cause the other port to create port noise? cause now that one port is moving more air through it.

 

[Sputter]

If you plug on port wouldn't that cause the other port to create port noise? cause now that one port is moving more air through it.

None that i've noticed but I haven't stuck my ear up close.

 

[Pyrrho]

If you plug on port wouldn't that cause the other port to create port noise? cause now that one port is moving more air through it.

Although that can be a problem, it is not the only problem with doing that. The other problem is that the maximum output at the higher frequencies is reduced. (You don't get deeper bass for nothing; if you did, there would be no reason to even have the ports in the first place.) Thus, if it was barely able to play loud enough before, it will no longer be able to play loud enough if one does that. I have some experience with this, as I have some tunable subwoofers myself. Not that it matters, mine are:

http://www.hometheaterhifi.com/volume_9_2/svs-cs-ultra-subwoofers-5-2002.html

Mine are designed for three options; leaving all ports open, plugging one port, or plugging two ports. Each port plugged does two things. First, it increases the depth of the bass. Second, it decreases the maximum output level that is possible. In my case, I have chosen to plug one port, which gives me fairly flat bass down to about 15 Hz, which I judge to be adequate, and do not wish to give up more volume for deeper bass than that.

So, what would happen with this Hsu subwoofer is that you can get deeper bass, but then you will be sacrificing the maximum volume you can get from it. Which is better depends upon one's specific requirements, and that is why Hsu has made the subwoofer such that one can use it more than one way.

 

[billy p]

Although that can be a problem, it is not the only problem with doing that. The other problem is that the maximum output at the higher frequencies is reduced. (You don't get deeper bass for nothing; if you did, there would be no reason to even have the ports in the first place.) Thus, if it was barely able to play loud enough before, it will no longer be able to play loud enough if one does that. I have some experience with this, as I have some tunable subwoofers myself. Not that it matters, mine are:

http://www.hometheaterhifi.com/volume_9_2/svs-cs-ultra-subwoofers-5-2002.html

Mine are designed for three options; leaving all ports open, plugging one port, or plugging two ports. Each port plugged does two things. First, it increases the depth of the bass. Second, it decreases the maximum output level that is possible. In my case, I have chosen to plug one port, which gives me fairly flat bass down to about 15 Hz, which I judge to be adequate, and do not wish to give up more volume for deeper bass than that.

So, what would happen with this Hsu subwoofer is that you can get deeper bass, but then you will be sacrificing the maximum volume you can get from it. Which is better depends upon one's specific requirements, and that is why Hsu has made the subwoofer such that one can use it more than one way.

and that is why all three of these subs arrived from the mfg with both ports open as described in each review. I wouldn't sacrifice one for the other...

 

[sharkman]

Yeah, it's a trade off between SPL's and extension. That's what the V T F subs are all about. Variable. Tuning. Frequency. What makes this sub possibly attractive to some is extension down to 16Hz by 'tuning' it. And the price, which is 500 less than the SVS model tested, for instance. The question is how much SPL do you give up to get 16 Hz? That's what I hope to find out when models like this get reviewed.

As far as the port noise goes, somehow I don't think Dr Hsu would design a sub whose ports made audible noise. It would be all over the net by now.

 

[ratso]

I think I figured out the problem with Audioholics reviews.
It has to do with the first page. You get a summary and a pros and cons column and for most that's all they really read, including myself.
Now when you get to the meat of the review and in the traditional audioholics style, things starts getting complicated (big words, numbers and formulas are used). And some of us just glaze over the words and go to the end.
When you have performance rating bars that show the HSU having only 4 bars and the Emotiva having 5, without really reading and understanding the meat of the review, one would think the Emotiva is the superior product.
It's not the reviewer's fault that some readers are lazy but hey, this is life if you have pictures and words, pictures win.

i have read this thread with a bunch of suprise and frankly, dissapointment. HSU subs are BUDGET subs, you guys do realize that don't you? i have never owned one so i have no dog in this hunt. however, they are a company that does something that i (and probably most of you) champion - they make a quality product at a REASONABLE price. however, because their graph shows that another sub goes a few db louder or a little lower (at TWICE THE PRICE remember) than everyone bags on it. one guy even wanted to return one before ever even listening to it (?). and you guys wonder why everyone pulled out of the shootout - this is why.

that being said, i agree with the above poster. it is a very good thing that audioholics goes so in-depth technically on their reviews (some of us - not me- might actually understand it ). but for most of us i think, it kind of bogs the reviews down. we lose interest. how about a different format. might i suggest (god i hate to say it) one kind of like stereophile does - where the tech talk and graphs are kept in a box off to the side, and the main review is more subjective, ie: what it sounds like.

BTW: not to bag on the reviewer, but to say "we didn't have time" to fully test all options on the sub is a little lame. if not enough time exists too do a thorough and fair review, especially seeing as how it has been admitted here it would actually make the sub sound better in a lot of cases, than don't do the review.

 

[shadyJ]

Audioholic's measurements were in some cases, 3 db down from Hsu's own released measurements. I would attribute this to the fact that Hsu probably used different tuning points to achieve those numbers. I think users will normally use this sub in a lower tuning point than what the reviewer used it in, as the VTF-15 has so much headroom to spare above 30 hz that no one will ever reasonably use it to to its fullest capability up there. I mean, who listens to anything at 120 db?