Submersive vs Rythmik - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #1 of 32 Old 07-07-2010, 11:18 PM - Thread Starter
Advanced Member
 
yelnatsch517's Avatar
 
Join Date: Nov 2006
Location: Los Angeles, CA
Posts: 980
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Which would be better, 1 Submersive or 2+ Rythmiks? I don't know how much Submersives are going for now, but I estimate it to be a bit over the price of 2 D15Se Rythmiks.

How does the Submersive compare with the Rythmiks in terms of SQ and SPL. I prioritize SQ much more than SPL even for HT use and the sub(s) will be going into a 2330 cu ft room, but the actual system sits in only a part of the room that comes out to 1080 cu ft.

Receiver: Denon 3311ci
L & R: 2x Energy RC-70
Surround: 2x Energy RC-10

I'll be getting the receiver tomorrow and the speakers hopefully by next week. I bought an extra pair of Energy RC-10s that I might use as the center, but most likely will eventually go with the RC-LCR. How would the subs pair with this system?

Oh, I might get an Emotiva XPA-3 in the future, but I doubt it would be necessary since the room is so small.
yelnatsch517 is offline  
Sponsored Links
Advertisement
 
post #2 of 32 Old 07-08-2010, 02:07 AM
Senior Member
 
tlag's Avatar
 
Join Date: Nov 2006
Posts: 401
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Co-located Rythmiks vs. one Submersive should be pretty similar. But the two Rythmiks will likely be easier to optimize placement of, and also provide smoother response over a larger listening area.
tlag is offline  
post #3 of 32 Old 07-08-2010, 06:04 AM
AVS Special Member
 
Bunga99's Avatar
 
Join Date: Jan 2007
Posts: 1,268
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked: 32
Just throwing this out there (just incase you were not aware).
The SubMersive (US only...for now) has recently had an upgrade from 1000Watts to 2400 watts. This version of the SubMersive is now called the SubMersive HP. It will be priced the same as the original SubMersive until July 16th then the price will go up ~300 bucks or so.
Bunga99 is offline  
post #4 of 32 Old 07-08-2010, 07:51 AM
Member
 
Bravo1's Avatar
 
Join Date: Sep 2009
Posts: 112
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I have a setup that is similiar to yours excluding the sub.

Onkyo HT-RC180
Energy RC-70 (Fronts)
Energy RC-LCR (Center)
Energy RC-10 (Rears)
Rythmik F12SE (Sub)

In my case I am filling an area that is about 3800 sqft and really I am happy overall. I am sure either one of your choices will work out well for you. Just the Submersive is one massive box, so placement may be a thing to consider. Rythmik's are known for their SQ but from what I understand the Submersive's are just as good but never experienced one from myself. Can always consider dual F15HP-SE's as well if the normal setup does not have enough power. I think Rythmik gives discounts for puchasing two at a time, so even then the price would come out close to a nice finish Submersive.
Bravo1 is offline  
post #5 of 32 Old 07-08-2010, 11:36 AM - Thread Starter
Advanced Member
 
yelnatsch517's Avatar
 
Join Date: Nov 2006
Location: Los Angeles, CA
Posts: 980
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
How much do Submersives go for nowadays anyway? Their website has been under construction for what seems like forever.

I'm really curious about the SQ of the Submersive vs the Rythmik. 1 Submersive HP would pump out the wattage of four F15HP Rythmiks. Not to mention, the Submersive is only a few inches larger than the D15SE. I like how inert the construction is of the Submersive. This might allow me to maybe use it as some sort of end table or maybe even place my surrounds on them? How inert are the Rythmiks? There's a video of 2 pennies on a Submersive on full blast. Surprisingly, the pennies didn't move even 1mm.
yelnatsch517 is offline  
post #6 of 32 Old 07-08-2010, 11:40 AM
AVS Special Member
 
hometheatergeek's Avatar
 
Join Date: Jan 2008
Location: Georgia
Posts: 2,326
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Liked: 31
Here you go.

With limited availability, orders will be taken via dedicated e-mail for Seaton Sound product inquiries. Please e-mail SeatonSound (at) comcast (dot) net if you are interested in purchasing

Hometheatergeek

aka AL
----------
My Current System
hometheatergeek is offline  
post #7 of 32 Old 07-08-2010, 02:01 PM
Senior Member
 
tlag's Avatar
 
Join Date: Nov 2006
Posts: 401
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Quote:
Originally Posted by Bunga99 View Post

Just throwing this out there (just incase you were not aware).
The SubMersive (US only...for now) has recently had an upgrade from 1000Watts to 2400 watts. This version of the SubMersive is now called the SubMersive HP. It will be priced the same as the original SubMersive until July 16th then the price will go up ~300 bucks or so.

And interestingly, if you're interested, says here there'll be SubMersives built with used amps from customer upgrades for some $300 cheaper than now.
tlag is offline  
post #8 of 32 Old 07-08-2010, 08:22 PM
AVS Special Member
 
monomer's Avatar
 
Join Date: Apr 2002
Location: up north
Posts: 1,767
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by yelnatsch517 View Post

...I'm really curious about the SQ of the Submersive vs the Rythmik...

That's really a question only someone that has heard both subs in the same environment with each sub set-up and dialed-in properly could have a valid (subjective) opinion on. Good luck finding this someone. I'll continue to pop into this thread to see if that someone shows up... I too am interested in seeing a SQ assessment/comparison.

"For deep bass, the listener is not really listening to the speaker, but rather, is listening to the room as it is being played by the speaker."
Juicy
Doggie Jabber
monomer is offline  
post #9 of 32 Old 07-08-2010, 08:36 PM
AVS Special Member
 
warlord260's Avatar
 
Join Date: Aug 2007
Location: kent,wa.
Posts: 1,350
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
If by same enviroment you mean same room, same placement,then yes that would be interesting.
warlord260 is offline  
post #10 of 32 Old 07-09-2010, 12:29 AM
AVS Special Member
 
CT_Wiebe's Avatar
 
Join Date: Nov 2003
Location: San Jose, CA
Posts: 6,437
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
yelnatsch517 -- First of all, the room size that you have to consider is the entire room (plus all volumes that are connected via room openings). Audio sounds do not know how much of a connected space you are using for your HT, it fills the entire space. Sub-woofers have to be able to pressurize the whole volume. Caveat: I do not have (and have not heard) either sub.

While both are excellent subs, the Submersive has better low-end performance (below 20Hz) and can deliver more audio power (SPL) -- from my research. Two D15SE Rythmiks are almost equal to the price of one Submersive, shipping costs not included.

From my, over 50 years of, experimenting with speaker systems, I would guess that (for your sized room) either choice would be good (2 Rythmik D15SE vs. one Submersive). The Submersive will play louder and should "dig deeper", IMHO, as I said. The 2 D15SEs (18" W x 18" D x 24 " H, each) will be slightly larger than a single Submersive (24.25" W x 17.5" D x 25.5" H).

Personally, I'm planning on using a single D15SE to replace my ancient Velodyne UDL-15. My room is larger than yours, but I don't play my system at "ear bleed" levels either. If I did want to push the volume up, then I would likely get a second D15SE, primarily since my room is sonically challenged, and would benefit more from dual subs placed at alternate locations.

Bunga99 -- As Mark Seaton, himself, has said, you shouldn't judge sub-woofer performance merely by the power capability of its amplifier. There are too many other factors that enter into the design of a good sub.

- Claus {non-Santa model}
CT_Wiebe is offline  
post #11 of 32 Old 07-09-2010, 06:03 AM
AVS Special Member
 
Bunga99's Avatar
 
Join Date: Jan 2007
Posts: 1,268
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked: 32
Quote:
Originally Posted by CT_Wiebe View Post

yelnatsch517 -- First of all, the room size that you have to consider is the entire room (plus all volumes that are connected via room openings). Audio sounds do not know how much of a connected space you are using for your HT, it fills the entire space. Sub-woofers have to be able to pressurize the whole volume. Caveat: I do not have (and have not heard) either sub.

While both are excellent subs, the Submersive has better low-end performance (below 20Hz) and can deliver more audio power (SPL) -- from my research. Two D15SE Rythmiks are almost equal to the price of one Submersive, shipping costs not included.

From my, over 50 years of, experimenting with speaker systems, I would guess that (for your sized room) either choice would be good (2 Rythmik D15SE vs. one Submersive). The Submersive will play louder and should "dig deeper", IMHO, as I said. The 2 D15SEs (18" W x 18" D x 24 " H, each) will be slightly larger than a single Submersive (24.25" W x 17.5" D x 25.5" H).

Personally, I'm planning on using a single D15SE to replace my ancient Velodyne UDL-15. My room is larger than yours, but I don't play my system at "ear bleed" levels either. If I did want to push the volume up, then I would likely get a second D15SE, primarily since my room is sonically challenged, and would benefit more from dual subs placed at alternate locations.

Bunga99 -- As Mark Seaton, himself, has said, you shouldn't judge sub-woofer performance merely by the power capability of its amplifier. There are too many other factors that enter into the design of a good sub.


I agree with every you said but just for the record.... I've spoke to Mark on the phone back in April (a couple of times) about this new SubMersive HP Amp. He's been testing it for a while and it outperforms the original in every way. I did not mean to make it sounds like (it has double the power, so its double output), If anyone thinks that from what I posted, I'm sorry for mis-leading you. I was just stating that if the op is seriously considering a SubMersive, why not get the upgraded version for a discount (until July 16th), I know I thought it was a good enough deal to order one for myself. I should have mine at some point today.
Bunga99 is offline  
post #12 of 32 Old 07-09-2010, 06:36 AM
AVS Club Gold
 
craig john's Avatar
 
Join Date: Oct 2003
Location: Lancaster, PA
Posts: 10,325
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 90 Post(s)
Liked: 319
Quote:
Originally Posted by CT_Wiebe View Post

Bunga99 -- As Mark Seaton, himself, has said, you shouldn't judge sub-woofer performance merely by the power capability of its amplifier. There are too many other factors that enter into the design of a good sub.

Agreed... but... a doubling of power will add 3 dB of output. So the new Submersive HP amp that more than doubles the power, (1,000 watts to 2,400 watts), will add slightly more than 3 dB of headroom. Assuming the drivers have some excursion capability in reserve to take advantage of the greater amplifier power, that's almost as good as adding a second subwoofer, (which will add 3 to 6 dB of output depending upon placement.)

Craig

Lombardi said it:
Perfection is not attainable, but if we chase perfection we can catch excellence."

My System

craig john is offline  
post #13 of 32 Old 07-09-2010, 08:10 AM
AVS Addicted Member
 
cschang's Avatar
 
Join Date: Mar 2003
Location: Manhattan Beach, CA
Posts: 14,769
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 28 Post(s)
Liked: 77
Is the new Submersive HP amp ICEpower based as well?

-curtis

Owner of Wave Crest Audio
Volunteer Mod at the Ascend Acoustics Forum
Like all things on the Internet, do your research, as forums have a good amount of misinformation.
Help beat breast cancer!

cschang is offline  
post #14 of 32 Old 07-09-2010, 09:35 AM
AVS Special Member
 
Mark Seaton's Avatar
 
Join Date: Jul 2000
Location: Chicago, IL, USA
Posts: 6,063
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 78 Post(s)
Liked: 285
Quote:
Originally Posted by cschang View Post

Is the new Submersive HP amp ICEpower based as well?

Hi Curtis,

No, but it is from the same OEM which supplies my 1000W amplifiers which incorporate the 1000W ICEpower module. This is a proprietary amplifier design they are building entirely here in the states and in house (even down to the circuit boards). There are other pro audio amplifiers which have related designs, this specific version being unique to my OEM. The only change from the original SubMersive amplifiers is the power section which drives the woofers and a 20A breaker in place of the fuse on the originals. The DSP controller, balanced inputs mounting plate and full cage are the all the same. The frequency response and total gain are matched with the old and new amps to keep things as clear as possible. The new amps now also utilize the 2nd DSP program adding a second starting response curve which shifts the outdoor response curve down to 15Hz vs. 19Hz of the original for larger rooms and those who want a little extra lift on the bottom.

The new amplifier is also a good deal more efficient than the ICEpower design at ~95% efficiency.

Mark Seaton
Seaton Sound, Inc.
"Make no little plans; they have no magic to stir men's blood..." Daniel H. Burnham
Mark Seaton is offline  
post #15 of 32 Old 07-09-2010, 10:07 AM
Advanced Member
 
Hudda's Avatar
 
Join Date: May 2007
Location: North Wales, PA.
Posts: 585
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 23
^^^

That's interesting. Makes sense as well given you said the entire amp is made here and the ICEpower module is made by B&O. So it's still a class D amp, more powerful than the previous amp and even MORE efficient than an ICEpower-based amp. Wow.

Chris
Hudda is offline  
post #16 of 32 Old 07-09-2010, 10:16 AM
AVS Addicted Member
 
cschang's Avatar
 
Join Date: Mar 2003
Location: Manhattan Beach, CA
Posts: 14,769
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 28 Post(s)
Liked: 77
Mark...that is great. I think it is great when improved technology improves audio...and enjoyment in general!

-curtis

Owner of Wave Crest Audio
Volunteer Mod at the Ascend Acoustics Forum
Like all things on the Internet, do your research, as forums have a good amount of misinformation.
Help beat breast cancer!

cschang is offline  
post #17 of 32 Old 07-09-2010, 12:31 PM
AVS Special Member
 
merrymaid520's Avatar
 
Join Date: Mar 2005
Location: Milwaukee WI
Posts: 1,446
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 20
To the OP,

I may be able to compare one Rythmik to the submersive when the WI audio boys GTG maybe sometime in the coming months. Our local buddy TJHUB just bought one from Mark with the new amp and I have the Rythmik. I would love for this comparison myself if we can arrange it. We live about 1.5 hours apart or so.

Sorry I could not be of any more help

Brandon
merrymaid520 is offline  
post #18 of 32 Old 07-09-2010, 02:36 PM - Thread Starter
Advanced Member
 
yelnatsch517's Avatar
 
Join Date: Nov 2006
Location: Los Angeles, CA
Posts: 980
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Quote:
Originally Posted by merrymaid520 View Post

To the OP,

I may be able to compare one Rythmik to the submersive when the WI audio boys GTG maybe sometime in the coming months. Our local buddy TJHUB just bought one from Mark with the new amp and I have the Rythmik. I would love for this comparison myself if we can arrange it. We live about 1.5 hours apart or so.

Sorry I could not be of any more help

Brandon


What are you talking about, you are a great help. I have patience, especially when it comes to buying things I want. I will eagerly wait for your comparison of the subs from the upcoming renowned WI GTG.

BTW, how inert is your subwoofer when watching movies? Does the enclosure vibrate, if so, how much? Would I be able to put my surrounds on them, maybe not directly but using some foam blocks between?
yelnatsch517 is offline  
post #19 of 32 Old 07-09-2010, 03:19 PM
AVS Special Member
 
merrymaid520's Avatar
 
Join Date: Mar 2005
Location: Milwaukee WI
Posts: 1,446
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 20
Quote:
Originally Posted by yelnatsch517 View Post

What are you talking about, you are a great help. I have patience, especially when it comes to buying things I want. I will eagerly wait for your comparison of the subs from the upcoming renowned WI GTG.

BTW, how inert is your subwoofer when watching movies? Does the enclosure vibrate, if so, how much? Would I be able to put my surrounds on them, maybe not directly but using some foam blocks between?

Again, it could be a while before another WI audio GTG, good thing you are patient I would not go as far to call us "renowned" - we are the WAC jobs

Anyway, the Rythmik is very inert. I have mine(D-15 SE) up front between my TV and left main on carpeting. The top moves very little if any during playback. I do not have anything on top but I imagine something of a pad then the surrounds on it would be more than sufficient.
The Rythmik truly excels with music and accurate bass all around...and goes deep! The only sub that I have heard that compares in SQ(Not output) is the JL fathoms which are very pricey.

Stay tuned.......
merrymaid520 is offline  
post #20 of 32 Old 07-09-2010, 04:59 PM - Thread Starter
Advanced Member
 
yelnatsch517's Avatar
 
Join Date: Nov 2006
Location: Los Angeles, CA
Posts: 980
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Well here is a review of the Submersive vs JL Fathom 113 I found.

Now the question is how does the Rythmik compare to the JL?
yelnatsch517 is offline  
post #21 of 32 Old 07-09-2010, 05:28 PM
AVS Special Member
 
merrymaid520's Avatar
 
Join Date: Mar 2005
Location: Milwaukee WI
Posts: 1,446
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 20
Quote:
Originally Posted by yelnatsch517 View Post

Well here is a review of the Submersive vs JL Fathom 113 I found.

Now the question is how does the Rythmik compare to the JL?

Did you mean against the submersive? I already compared my rythmik vs the jl at an older WI gtg....see thread for details
merrymaid520 is offline  
post #22 of 32 Old 07-09-2010, 05:41 PM
Advanced Member
 
TJHUB's Avatar
 
Join Date: Feb 2008
Location: Wisconsin
Posts: 607
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
I recently faced this same decision. I owned an SVS PB13-Ultra for the past two years and an SVS 20-39PC+ prior to that. It's not hard to be an SVS fan, and the PB13-Ultra was an amazing all around sub. The only reason I sold it was because I use my sub for 2-channel music. Music is my primary concern as I consider my setup a 2-channel system that is home theater capable. I just like it to be very capable.

As I was not happy with my PB13 for music, I had my sights set on a pair of Rythmik F15HP's. I really wanted the dual subs for hopefully better in-room frequency response, but I was very successful getting a flawlessly flat in-room response from the PB13 just using it's built-in single band PEQ. I was about to pull the trigger on the Rythmik's until a good friend told me to look into the SubMersive. So I did...

There is no doubt that choosing between dual Rythmik 15's and a SubMersive is a very difficult decision. For me, I really wanted the dual subs and the aesthetics of 2 subs on either side of my entertainment center. My wife was really looking forward to getting rid of the large PB13 and getting the smaller pair of subs. That was until I called Mark Seaton...

Mark did not sell me on the SubMersive. What he did was helped me figure out how to integrate his SubMersive with no bass management into my dual sourced setup (a Velodyne SMS-1). What did push me into the SubMersive is its dual opposed driver configuration, and the fact that he offered me a SubMersive HP. I couldn't pass up on the offer.

Back to the dual opposed drivers... One thing that I didn't like about my SVS 20-39PC+ was that the sub was far too light for the power it had. My setup is in my living room and it has a wood floor above a basement. The SVS cylinder would literally bounce and shake the floor when driven hard for HT. The down-facing driver and light weight was a problem. Fun sometimes, but I don't want to hear my room shaking vs the actual sound. When I got my PB13-Ultra, the front firing driver and heavy box was MUCH better. I could drive the sub much harder before my floor shook. But as it was a very powerful sub, the house shook anyway. I'm very curious as to how the SubMersive HP will perform in my room when driven hard. I'm hoping to hear more sound and less room shaking; at least for anything but bass heavy movies anyway.

Mark tells me I should see my new SubMersive HP next week Wednesday. I sure hope so as I've been subless for far too long now. I'm really looking forward to getting it all setup and listening to both music and driving it hard for HT.

So while I did wrestle with the decision, I feel like I made the right decision thus far. I'm sure I would have been happy with a pair of Rythmik's, but I'm thinking the SubMersive will be "better" for me.
TJHUB is offline  
post #23 of 32 Old 07-09-2010, 10:03 PM - Thread Starter
Advanced Member
 
yelnatsch517's Avatar
 
Join Date: Nov 2006
Location: Los Angeles, CA
Posts: 980
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
From other anecdotes of the Submersive, not only will your house shake, but it will flex. Even the normal Submersive should blow your PB13-Ultra out of the water. I wouldn't be surprised if the HP version blew your entire house off it's foundation. There is no doubt about it's SPL, but I hope it has equally good SQ. I'm looking forward to your review of the Submersive HP.

Quote:
Originally Posted by merrymaid520 View Post

Did you mean against the submersive? I already compared my rythmik vs the jl at an older WI gtg....see thread for details

Would you happen to have a link? I tried searching for it, but I'm not sure exactly what to search for.
yelnatsch517 is offline  
post #24 of 32 Old 07-10-2010, 05:46 AM
AVS Special Member
 
merrymaid520's Avatar
 
Join Date: Mar 2005
Location: Milwaukee WI
Posts: 1,446
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 20
merrymaid520 is offline  
post #25 of 32 Old 07-15-2010, 04:50 PM - Thread Starter
Advanced Member
 
yelnatsch517's Avatar
 
Join Date: Nov 2006
Location: Los Angeles, CA
Posts: 980
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Quote:
Originally Posted by merrymaid520 View Post

WI GTG link.......

http://www.avsforum.com/avs-vb/showt...ghlight=wi+gtg

Thanks for the link.

I have just one question:
According to Ilkka's Tests the Rythmik has incredibly high THD below 40Hz. If this is supposed to be a musical sub, what is actually going on? I have always theorized that group delay and spectral decay play a huge part on the SQ of a sub and why I stay away from PRs like the plague. These are two of the things the Rythmik has going for it. If you compare THD of Rythmik to the SVS PB13-Ultra, the SVS is actually lower, but people claim the Rythmik to have noticeably better SQ which intrigues me.

Rythmik:






SVS PB13-Ultra:



yelnatsch517 is offline  
post #26 of 32 Old 07-15-2010, 06:24 PM
Advanced Member
 
nith's Avatar
 
Join Date: Dec 2006
Posts: 638
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by yelnatsch517 View Post

Thanks for the link.

I have just one question:
According to Ilkka's Tests the Rythmik has incredibly high THD below 40Hz. If this is supposed to be a musical sub, what is actually going on? I have always theorized that group delay and spectral decay play a huge part on the SQ of a sub and why I stay away from PRs like the plague. These are two of the things the Rythmik has going for it. If you compare THD of Rythmik to the SVS PB13-Ultra, the SVS is actually lower, but people claim the Rythmik to have noticeably better SQ which intrigues me.

Brian responded to Ilkka's test in another forum. You read the thread here.

I need to do some damage control here :-)

As much as I like to quote Ilkka's result, I do think he didn't do a good job explaining the results. The source of confusion is the db label on the curve. A curve labelled 100db can be easily misinterpreted as 100db at every frequency. But it is clearly not. Actually, the subwoofer with the least extension actually measures best in distortion. As a result, most of the DIY subwoofer with -3db at 40hz measure better than others. The labelling is so misleading that one member of AVS forum even quoted two SDX15 in a 140L sealed has output of 120db at 20hz with distortion of blah blah... I remind him that 120db curve has such a severe roll-off that it has only 105db left at 20hz. Ilkka was never able to get 120db output them.


Back to SB12plus vs Directservo, the curve labelled as 100db and 105db actually only has 87db output and you can see it clearly saturates. When that happens, all the harmonic distortion figure is meaningless because it enters another area called amplitude modulation distortion (or compression). We need to measure how far off they are from the supposed output level. Even if we just check the distortion for fun, that 87db at 20hz has a 20% distortion. Our 12" has 95db max output. That is 8db more than SB12plus. In addition, our output curve giving 87db output at 20hz is actually labelled as 90db and the distortion is 10%. At 30hz, the max output of SB12 plus saturates at 97db. With distortion curve close to 18%. Ours distortion at 95db (30hz)is 5% and at 100db, the distortion is 10%. So we can interpolate the distortion at 97db is around 7%. Ours eventually will saturate at 105db. Again that is 8db difference. 8db is actually 6.25x in power. That means if the driver in SB12 plus driver were not the limiting factor, it will need 425*6.25=2650WRMS to match our output. That is more than what can be attributed to by the 33% increase in enclosure volume.

Again, in terms of distortion reduction, ours is about 2.5x smaller than SB12plus and that is also 8db. 2.5x in amplitude is 6.25x in power. In addition, our distortion is mostly 2nd order which is mellow and less harsh. SB12plus has more higher order distortion which is more audible (as a result of our loudness curve). The calculation above does not consider that aspect of distortion audibility. At 95db curve, we have 1% distortion at 40hz, and SB12plus has 6% distortion.

Harmonic distortion is not the only type of distortion. It is the easiest to measure and has been quoted more often. I have mentioned amplitude modulation distortion. Memory effect (or hysteresis) is another type. None of them are measured by Ilkka. Another issue is the perceived bass speed and articulation, which is affected by factors such as Qts value. Our Qts value is 0.3 in enclosure. That is 3x lower than other nonservo subs.
nith is offline  
post #27 of 32 Old 07-15-2010, 09:45 PM
AVS Special Member
 
monomer's Avatar
 
Join Date: Apr 2002
Location: up north
Posts: 1,767
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
And the clincher is Ilkka chose to get a Rythmik for use in his own personal system... coming from a guy that's heard and measured them all and then ends up choosing the Rythmik for his own personal use is really saying a lot.
Yelnatsch517... Those graphs keep showing up every month or two, if you would do a search you'll turn up a number of responses by Brian as well as others... still I suspect in another month someone else will again post those graphs or a link to them, this time in another thread, and posing yet the same questions...

"For deep bass, the listener is not really listening to the speaker, but rather, is listening to the room as it is being played by the speaker."
Juicy
Doggie Jabber
monomer is offline  
post #28 of 32 Old 07-16-2010, 01:04 AM - Thread Starter
Advanced Member
 
yelnatsch517's Avatar
 
Join Date: Nov 2006
Location: Los Angeles, CA
Posts: 980
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Quote:
Originally Posted by nith View Post

Brian responded to Ilkka's test in another forum. You read the thread here.

I need to do some damage control here :-)

As much as I like to quote Ilkka's result, I do think he didn't do a good job explaining the results. The source of confusion is the db label on the curve. A curve labelled 100db can be easily misinterpreted as 100db at every frequency. But it is clearly not. Actually, the subwoofer with the least extension actually measures best in distortion. As a result, most of the DIY subwoofer with -3db at 40hz measure better than others. The labelling is so misleading that one member of AVS forum even quoted two SDX15 in a 140L sealed has output of 120db at 20hz with distortion of blah blah... I remind him that 120db curve has such a severe roll-off that it has only 105db left at 20hz. Ilkka was never able to get 120db output them.


Back to SB12plus vs Directservo, the curve labelled as 100db and 105db actually only has 87db output and you can see it clearly saturates. When that happens, all the harmonic distortion figure is meaningless because it enters another area called amplitude modulation distortion (or compression). We need to measure how far off they are from the supposed output level. Even if we just check the distortion for fun, that 87db at 20hz has a 20% distortion. Our 12" has 95db max output. That is 8db more than SB12plus. In addition, our output curve giving 87db output at 20hz is actually labelled as 90db and the distortion is 10%. At 30hz, the max output of SB12 plus saturates at 97db. With distortion curve close to 18%. Ours distortion at 95db (30hz)is 5% and at 100db, the distortion is 10%. So we can interpolate the distortion at 97db is around 7%. Ours eventually will saturate at 105db. Again that is 8db difference. 8db is actually 6.25x in power. That means if the driver in SB12 plus driver were not the limiting factor, it will need 425*6.25=2650WRMS to match our output. That is more than what can be attributed to by the 33% increase in enclosure volume.

Again, in terms of distortion reduction, ours is about 2.5x smaller than SB12plus and that is also 8db. 2.5x in amplitude is 6.25x in power. In addition, our distortion is mostly 2nd order which is mellow and less harsh. SB12plus has more higher order distortion which is more audible (as a result of our loudness curve). The calculation above does not consider that aspect of distortion audibility. At 95db curve, we have 1% distortion at 40hz, and SB12plus has 6% distortion.

Harmonic distortion is not the only type of distortion. It is the easiest to measure and has been quoted more often. I have mentioned amplitude modulation distortion. Memory effect (or hysteresis) is another type. None of them are measured by Ilkka. Another issue is the perceived bass speed and articulation, which is affected by factors such as Qts value. Our Qts value is 0.3 in enclosure. That is 3x lower than other nonservo subs.

I'm fully capable of reading those graphs and understand them perfectly fine, at least to the extent to what you quoted. I was comparing the Rythmik to the PB13-Ultra, not the SB12Plus. At first I thought it was the PB12-Ultra in the quote since that would at least be somewhat similar to the graphs I posted. I kept rereading the quote and couldn't for the life of me understand what the heck he was saying because I was looking at the PB12-Ultra. I was utterly confused because the numbers did not match at all.

If you look at the graphs I posted, the PB13-Ultra hits 107dB @ 20Hz during the 110dB sweep with 10% THD. But like I said, the Rythmik wins in the Group Delay and Spectral Decay area. What's amazing is the TC Sounds LMS5400 in a 100L sealed hits 104dB @ 20Hz from the 115dB sweep with 10% THD, but has similarly low group delay and spectral decay as the Rythmik. Now that is amazing.

TC Sounds LMS 5400 100L Sealed
yelnatsch517 is offline  
post #29 of 32 Old 07-18-2010, 10:08 AM
Exclusively Servo
 
Rythmik's Avatar
 
Join Date: Aug 2005
Location: Austin
Posts: 1,836
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 23 Post(s)
Liked: 74
Quote:
Originally Posted by yelnats 517 View Post

If you look at the graphs I posted, the PB13-Ultra hits 107dB @ 20Hz during the 110dB sweep with 10% THD. But like I said, the Rythmik wins in the Group Delay and Spectral Decay area. What's amazing is the TC Sounds LMS5400 in a 100L sealed hits 104dB @ 20Hz from the 115dB sweep with 10% THD, but has similarly low group delay and spectral decay as the Rythmik. Now that is amazing.
TC Sounds LMS 5400 100L Sealed

I think Nith was referring to SB12 as he thought you would have compared a sealed sub with a sealed sub. If you are interested in a vented sub, we will have a model coming up in a month to 6 weeks. That should have performance similar to PB13 ultra with the improvement from servo.

One thing you may have overlooked in the graph is the so-called "compression" curve. There are two sources of compression: 1) is caused by voice coil temperature increase, and 2) caused by amp clipping. The latter is temporary. As soon as the amp leaves clipping region, the response curve will be back to normal. The first source however takes longer time to dissipate. If you check our curves, the compression mainly comes from amp clipping at the lower end of the frequency. On PB13 ultra non servo subs, you can see compression at 60hz and the port tuning frequency. These points are the impedance minimal points where rise in voice coil temperature account for 90% of the impedance change and hence major response reduction. On the impedance peak points, voice coil temperature rises accounts only 10% (e.g., voice coil DCR is 3ohms, and peak is 30ohms). So you know where to look for thermal compression. I understand the only way to clarify these is for us to send a vented sub to UK or Ilkka for a similar test. BTW, there are discussion on how voice coil inductance affects the sub's performance. Here is an example that it begins to affect the thermal compression curve well within the subs operating frequency range.

BTW, there is another test with LM5400 plus an LT next to the one you referred to. You can see the LT circuit adds a bit more on group delay. That test is more an apple-to-apple comparison even though you can say ours is 12" and LM5400 is 18",...blah blah blah..
Rythmik is offline  
post #30 of 32 Old 07-18-2010, 01:22 PM - Thread Starter
Advanced Member
 
yelnatsch517's Avatar
 
Join Date: Nov 2006
Location: Los Angeles, CA
Posts: 980
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Quote:
Originally Posted by Rythmik View Post

I think Nith was referring to SB12 as he thought you would have compared a sealed sub with a sealed sub. If you are interested in a vented sub, we will have a model coming up in a month to 6 weeks. That should have performance similar to PB13 ultra with the improvement from servo.

One thing you may have overlooked in the graph is the so-called "compression" curve. There are two sources of compression: 1) is caused by voice coil temperature increase, and 2) caused by amp clipping. The latter is temporary. As soon as the amp leaves clipping region, the response curve will be back to normal. The first source however takes longer time to dissipate. If you check our curves, the compression mainly comes from amp clipping at the lower end of the frequency. On PB13 ultra non servo subs, you can see compression at 60hz and the port tuning frequency. These points are the impedance minimal points where rise in voice coil temperature account for 90% of the impedance change and hence major response reduction. On the impedance peak points, voice coil temperature rises accounts only 10% (e.g., voice coil DCR is 3ohms, and peak is 30ohms). So you know where to look for thermal compression. I understand the only way to clarify these is for us to send a vented sub to UK or Ilkka for a similar test. BTW, there are discussion on how voice coil inductance affects the sub's performance. Here is an example that it begins to affect the thermal compression curve well within the subs operating frequency range.

BTW, there is another test with LM5400 plus an LT next to the one you referred to. You can see the LT circuit adds a bit more on group delay. That test is more an apple-to-apple comparison even though you can say ours is 12" and LM5400 is 18",...blah blah blah..

Yea, I noticed the compressions and impedance spikes. I also saw the LMS 5400 LT, but didn't post it because the non LT actually seemed to perform better. Since you say thermal compression is a major concern, how would your direct servo drivers and amps work in something like Bosso's Raven design? Dual opposed drivers with active cooling and direct servo. That would be the ultimate sub?
yelnatsch517 is offline  
Reply Subwoofers, Bass, and Transducers

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off