HSU VTF-15H Subwoofer Review

[Ron Temple]

VTF-15H x2
One Port open/Q=.7/EQ1 NF / EQ2 FF
Room is 4500 cu ft irregular. (retangular with one corner open to wetbar and workout alcove)

That's a great looking FR @ 75dbs. What it doesn't show is what happens when you increase the volume. From the cuts, you've had to eliminate alot of response above 30hz to get flat. If with the volume increase you stay fairly flat, I'd suppose that your output would be effected. That's not a bad thing if you never really crank it. I've never doubted the VTF15H would give terrific in room performance. All the negativity about this sub is in comparison to it's rivals or intimated output claims.

I don't know if the SMS can handle 100db sweeps, but it would be interesting to see what the curve looks like there.

 

[Sputter]

That's a great looking FR @ 75dbs. What it doesn't show is what happens when you increase the volume. From the cuts, you've had to eliminate alot of response above 30hz to get flat. If with the volume increase you stay fairly flat, I'd suppose that your output would be effected. That's not a bad thing if you never really crank it. I've never doubted the VTF15H would give terrific in room performance. All the negativity about this sub is in comparison to it's rivals or intimated output claims.

I don't know if the SMS can handle 100db sweeps, but it would be interesting to see what the curve looks like there.

I would have like to been able to do that, the sms only goes as high as 87db.
Though, from 75db to the sms limit the curve stayed the same.

Jim

 

[Paul_Apollonio]

Thanks for your reply Paul.
Clearly your knowledge is greater than mine, that's why I asked about the outside/indoor question. I can appreciate the work you've put into it.
I'm not a detractor, i'm just trying to understand.

Jim

No sweat man. I appreciate that you guys enjoyed the article. It was an education (mostly in frustration at having to learn new software).

 

[Paul_Apollonio]

That's a great looking FR @ 75dbs. What it doesn't show is what happens when you increase the volume. From the cuts, you've had to eliminate alot of response above 30hz to get flat. If with the volume increase you stay fairly flat, I'd suppose that your output would be effected. That's not a bad thing if you never really crank it. I've never doubted the VTF15H would give terrific in room performance. All the negativity about this sub is in comparison to it's rivals or intimated output claims.

I don't know if the SMS can handle 100db sweeps, but it would be interesting to see what the curve looks like there.

100 Db at 20 Hz is about as loud as 60 db at 1000 Hz. At 75 db, you are at the bare threshold of audibility at 20 Hz. What is it about "LOUDNESS does NOT equal SPL" that is not abundantly clear from the nearly 100 year old Fletcher Munson Loudness curves? Loudness is measured in Phons, NOT SPL. We measure in SPL because we want the equipment to be linear. Our ears are not. If ALL YOU GET AT 20 Hz is 100 Db, that is a mere whisper in your ear. The LOWER you go, the MORE SPL we need for a given sensation of loudness. EVERYONE!! Repeat after me. LOUDNESS DOES NOT EQUAL SPL!!
Now go here and look !!!
http://home.fuse.net/engineering/chime_dimensions/fletcher_munson.jpg
Then when you are done, go here:
http://en.wikipedia.org/wiki/Phon
Guys, this is not difficult to comprehend if you spend more than a couple of seconds. Again, 100 db at 20 Hz is a WHISPER.... And yes, the Hsu can put out 100 db at 20 hz, look at the CEA figures shown in the tables. THOSE are the maximum peaks with tolerable distortion. This was the core of the article. Now, who doesn't like my dog? (LOL)

 

[gene]

RE: smooth and pretty SMS-1 measurement graphs

VTF-15H x2
One Port open/Q=.7/EQ1 NF / EQ2 FF
Room is 4500 cu ft irregular. (retangular with one corner open to wetbar and workout alcove)

I hope you do realize the SMS-1 output is limited to 1/3rd octave resolution.

See: http://www.audioholics.com/education/loudspeaker-basics/audio-measurements

If you want meaningful measurements and EQ correction for your subs, you should invest in an external measurement device with at least 1/12th octave resolution.

 

[Sputter]

I hope you do realize the SMS-1 output is limited to 1/3rd octave resolution.

See: http://www.audioholics.com/education/loudspeaker-basics/audio-measurements

If you want meaningful measurements and EQ correction for your subs, you should invest in an external measurement device with at least 1/12th octave resolution.

I'm aware of that Gene. It's a easy tool to use and it's helpful in it's limits imho. i'll read through your link.

 

[Sputter]

No sweat man. I appreciate that you guys enjoyed the article. It was an education (mostly in frustration at having to learn new software).

However, (isn't there always a "but or however" lol) I don't agree with some of your subjective comments which is fine as we all have our views.

Jim

 

[jeanseb]

100 Db at 20 Hz is about as loud as 60 db at 1000 Hz. At 75 db, you are at the bare threshold of audibility at 20 Hz. What is it about "LOUDNESS does NOT equal SPL" that is not abundantly clear from the nearly 100 year old Fletcher Munson Loudness curves? Loudness is measured in Phons, NOT SPL. We measure in SPL because we want the equipment to be linear. Our ears are not. If ALL YOU GET AT 20 Hz is 100 Db, that is a mere whisper in your ear. The LOWER you go, the MORE SPL we need for a given sensation of loudness. EVERYONE!! Repeat after me. LOUDNESS DOES NOT EQUAL SPL!!
Now go here and look !!!
http://home.fuse.net/engineering/chime_dimensions/fletcher_munson.jpg
Then when you are done, go here:
Phon - Wikipedia, the free encyclopedia
Guys, this is not difficult to comprehend if you spend more than a couple of seconds. Again, 100 db at 20 Hz is a WHISPER.... And yes, the Hsu can put out 100 db at 20 hz, look at the CEA figures shown in the tables. THOSE are the maximum peaks with tolerable distortion. This was the core of the article. Now, who doesn't like my dog? (LOL)

Thanks for this really interesting physic fact. So, following this theory, wouldn't trying to equalize our frequency response (in the low end) to a flat line bring a negative effect on our system? If so, why do equalizing devices, such as SMS-1 , XT, XT32, etc. try to do bring our response to a flat line?

 

[zhimbo]

Thanks for this really interesting physic fact. So, following this theory, wouldn't trying to equalize our frequency response (in the low end) to a flat line bring a negative effect on our system? If so, why do equalizing devices, such as SMS-1 , XT, XT32, etc. try to do bring our response to a flat line?

It isn't the job of the equalization programs, etc. to do that. Their job is to present the sound source as accurately as possible. Things that should be heard loudly need to be mixed loud. The recording and mixing is where the sound is made; your equipment's job is to reproduce it.

 

[Nuance AH]

I thought this might be pertinent info.

AVS Forum - View Single Post - Rythmik FV12 or Outlaw LFM1-EX?

 

[ack_bak]

Kudos to Gene and Audioholics for listening.

 

[Craigslist Joe]

I'd be curious to see what the HSU driver and cabinet would sound like with a servo controller and a little bigger amplifier...

 

[timoteo]

CJ:
The amp & the driver in the VTf-15H both run out of steam at around the same time. The driver is extremelly efficient & 350w rms is plenty for it. Adding a larger amp to the driver wouldnt help it get louder. Distortion maybe. Dr.Hsu knows his stuff. This is a great performer for <$1000 hands down!!

 

[Sputter]

Kudos to Gene and Audioholics for listening.

Have they posted the correct numbers? I haven't see it.

 

[Sputter]

I'd be curious to see what the HSU driver and cabinet would sound like with a servo controller and a little bigger amplifier...

It's not a matter of swaping parts. It was designed as a unit.

 

[gene]

Have they posted the correct numbers? I haven't see it.

yes the updated data tables are located in this article and its supporting thread and all reviews going forward.

see:Audioholics Subwoofer Measurement Data Compilation & Report &mdash; Reviews and News from Audioholics

{edit: weird the title shows its updated in the article but the file still caches to the old one . Guys please confirm when you click the file at the bottom of the article if it opens a single PDF file or a Zip file with one PDF and one excel. Its supposed to just open a PDF}

 

[Sputter]

yes the updated data tables are located in this article and its supporting thread and all reviews going forward.

see:Audioholics Subwoofer Measurement Data Compilation & Report &mdash; Reviews and News from Audioholics

{edit: weird the title shows its updated in the article but the file still caches to the old one . Guys please confirm when you click the file at the bottom of the article if it opens a single PDF file or a Zip file with one PDF and one excel. Its supposed to just open a PDF}

Gene, on the first page shows a link and it's linked to the measurement pdf.

Jim

P.S. Thanks Gene for the update, it's greatly appreciated.

 

[gene]

Gene, on the first page shows a link and it's linked to the measurement pdf.

Jim

yes I see it's working now. thanks.

 

[timoteo]

Yes everything is linking up for me on my iphone just fine. Thanks again posting all that. This whole time i didnt know what room size rating audioholics gave the VTF-15H. I'm happy to know that it received the Extreme, >5000cuft, rating right along with the other greats (FV-15HP & PB-13U).

In fact, i have mine in my livingroom that is opened up to some other areas of my home. Just the other day i did an exact measurement of the entire space that is open/connected to the livingroom. I closed all the doors that i possibly could & still got an >8600cuft area. Yet, even with that large of a space, the 15H sounds & feels absolutely incredible. Not only that but it measures nearly flat as well (with a little help from EQ to pull a peak down).

There are other wonderful subs on the market along with the VTF-15H, but for under $1000 its really in a league of it's own!!

 

[rkl525]

Yes everything is linking up for me on my iphone just fine. Thanks again posting all that. This whole time i didnt know what room size rating audioholics gave the VTF-15H. I'm happy to know that it received the Extreme, >5000cuft, rating right along with the other greats (FV-15HP & PB-13U).

In fact, i have mine in my livingroom that is opened up to some other areas of my home. Just the other day i did an exact measurement of the entire space that is open/connected to the livingroom. I closed all the doors that i possibly could & still got an >8600cuft area. Yet, even with that large of a space, the 15H sounds & feels absolutely incredible. Not only that but it measures nearly flat as well (with a little help from EQ to pull a peak down).

There are other wonderful subs on the market along with the VTF-15H, but for under $1000 its really in a league of it's own!!

Indeed, the VTF-15H is a great subwoofer. However, I don't think that it is in the same league with the other two. looking at the charts, it is roughly 4 dB behind the FV15HP at nearly every measured frequency.

Rythmik FV-15HP CEA Test Performance
Frequency Maximum Peak SPL @ 1 Meter RMS SPL @ 2 Meters
20 Hz 116.5 dB 107.5 dB
25 Hz 122.0 dB 113 dB
32 Hz 126.8 dB 117.8 dB
40 Hz 129.0 dB 120 dB
50 Hz 128.9 dB 119.9 dB
63 Hz 128.7 dB 119.7 dB


Hsu Research VTF-15H CEA Test Performance
Frequency Maximum Peak SPL @ 1 Meter RMS @ 2 meters
20 Hz 112.9 dB 103.9 dB
25 Hz 118.8 dB 109.8 dB
32 Hz 122.0 dB 113 dB
40 Hz 124.7 dB 115.7 dB
50 Hz 124.7 dB 115.7 dB
63 Hz 124.6 dB 115.6 dB