Finnish subwoofer shootouts

[Ilkka]

We will have manufacturer input from as many of the major players that are interested. As for THD, I suggest reading up on the series of articles we did on human hearing perception as a starting point.

http://www.audioholics.com/techtips/roomacoustics/HumanHearing.php

Of course two years ago many people though audio cables suffered ill effect from strand jumping, but we all know better now don't we

http://www.velodyne.com/velodyne/tech/faqanswer.aspx?ID=12&sid=653u856j

There is a good link too.

BTW, I did read your link, but they only praised a low THD figures? So where does this "one can not hear under 100% THD" claim comes from?

"Making use of low-distortion drivers and using multiples of the same drivers (when warranted) are just a couple examples of factors that can contribute to a clean, musically accurate sounding loudspeaker system. Of course, running a loudspeaker system at low levels keeps (as we’ve already seen) driver non-linearities minimized."

That is an odd statement to say as these metrics do play a big part in determining bandwidth and max SPL. Its almost like saying RLC data has no relevance on cable performance

No no, you missed my point. Of course they do affect, but one can not say anything certain from them. Sub with a long throw 10" driver in a reflex box, powered with 300 Watts can easily beat a small throw 15" driver in a sealed box, powered with 1000 Watts. So one can not just look at the specs (driver size, cabine size, amp power etc.) and say "this sub will out perform this sub". That's why we need thorough measurements.

 

[silversurfer]

That's why we need thorough measurements.

Ahhh....now we are getting somewhere. Can you equate how a subwoofer will sound according to your measurements?

To give you warning on where I am going with this, are you familiar with the papers written by Floyd E. Toole? I think he has been referenced over on the AVS threads.

 

[craigsub]

Thanks. But I don't think one needs to be sensible to see the slant.

Ya think ?

We are conducting a blind listening test on Sunday, the 20th, with all these subwoofers available for audition : Velodyne DD-18, SVS PB12-Ultra, Axiom EP-600 and Rocket UFW-12.

We have attending two SVS exclusive owners, a dual SVS/Axiom owner, a Rocket UFW-10 guy, and "bossobass", the best bass ear in the U.S.... I will just be the moderator. Or Roadie, depending on your point of view...

 

[silversurfer]

That should be fun.

Can you grab some non-owners as well. I think that would be very helpful.

 

[craigsub]

Bossobass is a non owner - he has built several subwoofers himself, and currently uses a Quad Tumult set up in two sealed boxes.

I think another gent is coming who owns a Velo - but it is an older 15 inch ported model.

 

[silversurfer]

No Ilkka?? How much is a round trip ticket from Finland? More or less than the cost of a EP600?

 

[craigsub]

No Ilkka?? How much is a round trip ticket from Finland? More or less than the cost of a EP600?

It would be a pleasure to invite Ilkka into our home. In fact, I will pay for his ticket if he comes.

 

[The Dukester]

test

So just where is this blind test taking place? Anyone bringing an HSU to the shootout?!

 

[craigsub]

So just where is this blind test taking place? Anyone bringing an HSU to the shootout?!

We are in Pennsylvania - I have a pair of VTF-3 HO's on order, but they aren't going to make it on time.

However, perhaps a part II in January ...

 

[gene]

Not for nothing, but it looks like the Axiom driver was pasted into this photo At the very minimal it doesn't even look like its to scale.

As per Mark Sanfilipo's Comments (our Loudspeaker Guru)
The comparisons made between drivers by virtue of magnet size is a farse. There exists an upper limit to gap field strength imposed by the saturation magnetization of the low-carbon steel polepiece & front plate (around 11 kGauss or so). So the big-is-good, bigger-is-better, biggest-is-best school of thought is a marketing ploy and usually doesn't indicate quality. Anything more than needed to get the job done correctly is a waste. Period.

 

[Ilkka]

Not for nothing, but it looks like the Axiom driver was pasted into this photo At the very minimal it doesn't even look like its to scale.

As per Mark Sanfilipo's Comments (our Loudspeaker Guru)
The comparisons made between drivers by virtue of magnet size is a farse. There exists an upper limit to gap field strength imposed by the saturation magnetization of the low-carbon steel polepiece & front plate (around 11 kGauss or so). So the big-is-good, bigger-is-better, biggest-is-best school of thought is a marketing ploy and usually doesn't indicate quality. Anything more than needed to get the job done correctly is a waste. Period.

I have absolutely nothing to do with that edited photo. Yes, the Axiom driver is taken from my original photo, but nothing else. (flash makes the cone look yellow)

 

[bossobass]

Some comments on my photo:

Yes, the Axiom driver was lifted from Ilkka's article and pasted onto my originally posted photo by others.

It is indeed not to scale with the other drivers.

I originally posted the picture to show that a similar comparison photo could easily be made that would show the 'Ultra' driver to be 'whimpy' when only visual examination is employed.

The next point is that the 'Ultra' driver in the photo is in fact, not an Ultra driver. This driver is a remnant of my years ago testing of dozens of 12" drivers, and was not a very good performer in spite of it's 42 pound weight.

The 'Ultra' driver does indeed use the same cast basket as the current real Ultra driver, which basket is readily available to build various configurations of 12" driver upon. I configured this driver approximately a year before the Ultra driver appeared in public.

The driver in the photo is actually a better constructed one in that it has a fine mesh that protects the gap from external contamination, whereas the Ultra driver's gap is exposed, and also has a precision machined stage for the spiders.

All of that aside, there is absolutely no way to tell if the 'Ultra' driver in the photo is a good, great or terrible performing 12" driver.

Looking at and weighing a driver tells you what the driver looks like and how much it weighs...nothing more.

I still am curious as to why the Ultra driver was compared to the Axiom driver when it was actually the PB10 that was measured in the shootout

The PB10's driver ain't much to look at, and doesn't weigh much compared to the Ultra driver either, is my guess. This would emphasize the point of the summary, which apparently was that the SVS 10" sub beats the Axiom 12" sub and it's because the Axiom sub's driver is much whimpier that the Ultra's driver...get it? Neither did I.

Bosso

 

[Ilkka]

I still am curious as to why the Ultra driver was compared to the Axiom driver when it was actually the PB10 that was measured in the shootout

That was just because of the previous Ultra/EP-600 comparisons over at AVS. And I do think that it was also more fair to both of them, since Ultra is much closer to EP-600 than the PB10 when regarding the money side.

The PB10's driver ain't much to look at, and doesn't weigh much compared to the Ultra driver either, is my guess. This would emphasize the point of the summary, which apparently was that the SVS 10" sub beats the Axiom 12" sub and it's because the Axiom sub's driver is much whimpier that the Ultra's driver...get it? Neither did I.

Bosso

I have already popped the PB10 open and I will take a couple of pictures of its driver too. Maybe next to Axiom too. I don't think it has to shame, even though it's only a 10 incher. But as you said, one can not say much from the driver itself, that's why I prefer measurements.

 

[craigsub]

That was just because of the previous Ultra/EP-600 comparisons over at AVS. And I do think that it was also more fair to both of them, since Ultra is much closer to EP-600 than the PB10 when regarding the money side.


I have already popped the PB10 open and I will take a couple of pictures of its driver too. Maybe next to Axiom too. I don't think it has to shame, even though it's only a 10 incher. But as you said, one can not say much from the driver itself, that's why I prefer measurements.

I prefer listening. I spent a whole hour last night trying to listen to a chart. It did nothing for me.

 

[fergusonv]

GRRRRR.... Can't a person escape this madness and bickering? Have you got a arguement going on at Home Theater Forum yet?

 

[scenaria]

I received a EP500 last week... I honesly couldnt be happier. If anyone has an SVS in the orlando area and wants to do some tests gimme a shout

 

[mulester7]

.....very interesting thread....looking forward to a report of the 20th.....

 

[Buckeyefan 1]

Photos

I have already popped the PB10 open and I will take a couple of pictures of its driver too. Maybe next to Axiom too. I don't think it has to shame, even though it's only a 10 incher. But as you said, one can not say much from the driver itself, that's why I prefer measurements.

Many of you have already seen these photos from our trip to SVS. Just to reiterate the size (and nothing more), here's some photos again.

Ultra

Plus and Ultra

ISD and Plus

 

[MacManNM]

Eugene, I believe the 2nd pic is the ISD and ultra. The third pic is the plus and ISD. If i remember right the ISD has a stamped steel frame and the plus/ultra have alum frames.

 

[MacManNM]

Ilkka,
I think you did a nice job on the measurements.

One thing I did notice that seems to hold true to my listening tests of the SVS units. They all seem to start to peter out ~50Hz (-6db point was around there for most of the measurements). When we went and listened to them, this was the impression I got. I would also like to say that I do strongly recommend the SVS for HT use, but if you want to do serious music listening, you are going to need a pair of loudspeakers capable of going down to~40Hz to use these subs, and make the integration seamless. I simply do not believe these subs work well with smallish loudspeakers (small towers, bookshelves etc.) Now the PB10 seems to be a good compromise for this. It seems to extend pretty flat out to 100 or so, yet maintain the low end pretty well. Good sub.