This looks like a good value compared to the rest of the manufactured market.
http://www.hsuresearch.com/products/vtf-15h.html
http://www.hsuresearch.com/products/vtf-15h.html
Quote:
Originally Posted by mjg100 /forum/post/19460074
Does look like a pretty good sub. Identical performance to the PB-13 at a lot less money.
Quote:
Originally Posted by bossobass /forum/post/19462398
I'm generally a Hsu fan, but I'm having a hard time swallowing the 350W +6dB of burst power, as well as the posted max output numbers. The driver would have to be 99dB sensitive, making the posted FR questionable.
My 2 cents.
Bosso
Quote:
Originally Posted by bossobass /forum/post/19462398
I'm generally a Hsu fan, but I'm having a hard time swallowing the 350W +6dB of burst power, as well as the posted max output numbers. The driver would have to be 99dB sensitive, making the posted FR questionable.
My 2 cents.
Bosso
Quote:
Originally Posted by penngray /forum/post/19464762
have you posted in the HSU thread...I remember them saying the amp has 1200 or 1400Watt peaks.
The measurements are CEA2010 standard measurements and HSU isnt a company to lie completely about something.
Granted I agree they can "Spin" stuff. The ULS-15 "Flat to 10Hz" BS was complete spin but that is what Marketing departments do. They should be pushing to the edge to sell a product so I have no problem with that. People online are always available to prove what is really true.
Quote:
Originally Posted by t6902wf /forum/post/19460109
Yea, two of those for a couple grand is a pretty good deal.
Not DIY good deal but a good deal.
Quote:
Originally Posted by MKtheater /forum/post/19464890
Except that you got a dts-10 for around a grand. That is a much better deal.
Quote:
Originally Posted by mjg100 /forum/post/19462886
The posted numbers were for 1 meter, not two meters.
Quote:
Originally Posted by penngray /forum/post/19464762
have you posted in the HSU thread...I remember them saying the amp has 1200 or 1400Watt peaks.
The measurements are CEA2010 standard measurements and HSU isnt a company to lie completely about something.
Quote:
Originally Posted by villastrangiato /forum/post/19464451
In fact, because most low q drivers have a high Qms:Qes ratio - in ported alignments they tend to exhibit the opposite behavior - less control at high excursion. That has been my experience and over the years - one reason why I've gravitated towards higher Qts drivers.
Quote:
Originally Posted by bossobass /forum/post/19465682
I don't know of any amp that has +6dB of burst capability
Quote:
Originally Posted by bossobass /forum/post/19465682
Soon we'll be seeing under specifications:
Max output: Teeth rattling, pants flapping.
Extension: Really, really, really deep.
Plate amp: 20,000W peak (150W RMS).
Bosso
Quote:
Originally Posted by Mrkazador /forum/post/19466053
Slightly off-topic but how does one calculate triangle ports in winisd? I'm not very good at math...
Quote:
Originally Posted by noah katz /forum/post/19465952
Where are you guys seeing output numbers?
Quote:
Originally Posted by bossobass /forum/post/19465682
Yes, I'm aware of the specifics. I still doubt the numbers.
I respect Dr. Hsu and have a good relationship with Pete, so I prefer to keep out of their threads, but this is the DIY section and the subject has been broached.
I don't know of any amp that has +6dB of burst capability, so I'd like to see more specific data to confirm that fact. Since they posted the spec, I don't feel it's out of line to question the specifics.
I'm also a bit ruffled at the recent trend to use a pro sound driver and post high max output capability at 63Hz vs 20Hz, but then post a +/-2dB response (which really means +0/-4dB, but is still shows the max numbers at single frequencies to be misleading) from 20-200Hz (or whatever).
Since the PB13Ultra is a proven entity, tested by an irreproachable source, the comparisons are already flying, but based on the manufacturer's posted numbers, which I doubt anyone with credibility will verify.
SVS, whose marketing jargon sometimes borders on the absurd, posts a response of +/-3dB 18-150Hz, but they also post a confirming GP frequency response magnitude graph which is verified by Ilkka.
The CEA #s for the Ultra show 20Hz vs 63Hz max output to have a 6dB difference, which can be said to be +/-3dB.
The Hsu posted numbers show an 11dB difference from 20Hz vs 63Hz, which can't be construed to be +/-2dB by any method.
I prefer that they just say it's a great sub for the money and leave it at that.
Why all of a sudden are we adding +6dB to a 2M GP number? GP adds +6dB to an anechoic free air number, thus the reason to move the GP distance to 2M.
Ed's, Ilk's and Charlie's efforts over the past decade are slowly being eroded and tossed out the window. As you say, that's what marketing folks do for a living, but that doesn't change my perspective.
Soon we'll be seeing under specifications:
Max output: Teeth rattling, pants flapping.
Extension: Really, really, really deep.
Plate amp: 20,000W peak (150W RMS).
Even used car retailers have to put the paragraph of micro-fine print at the bottom of the ad while the voice over is spewing BS.
Hey, maybe the numbers are all good. I love to be proven wrong. But I tend to not want to compare Ilkka's PB ULtra numbers to Hsu's own test results numbers.
Bosso
Quote:
Originally Posted by bossobass /forum/post/19465682
The Hsu posted numbers show an 11dB difference from 20Hz vs 63Hz, which can't be construed to be +/-2dB by any method.
Quote:
Originally Posted by NicksHitachi /forum/post/19466765
They do think highly of their stuff.
They also use the term "distortion free output" a lot when questioned about their numbers, and no output is "distortion free" its all relative.
Quote:
Originally Posted by craigsub /forum/post/19467112
By CEA2010 standards, THD can be quite high ... and the actual tone bursts are quite short.
Here are the standards for each distortion component:
2nd Harmonic: 31.6%
3rd Harmonic: 17.8%
4th harmonic: 10%
5th harmonic: 10%
6th-8th harmonics: 3.16% each
9th and above: 1% each
Doing the math for THD is simple enough from here.
Tone burst length is as follows:
20 Hz: .325 second
25 Hz: .260 second
31.5 Hz: .206 second
40 Hz: .163 second