Are three inexpensive subs better than one expensive sub-Dr. Earl Geddes Approach - Page 4 - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #91 of 2083 Old 02-25-2009, 02:34 PM
AVS Addicted Member
 
sivadselim's Avatar
 
Join Date: Oct 2004
Location: CO
Posts: 16,081
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 51 Post(s)
Liked: 68
Quote:
Originally Posted by tvckmiller View Post

I am currently running two subs by simply using a splitter at the back of the preamp. What is the most effective method for connecting more than that? My subs are co-located now for output. I have heard about daisy chaining but not real familiar with it. Would this be a better solution for co-located subs?

Another splitter. Depending upon the sub's locations and your cabling needs/restraints, you can put the splitters wherever they make the most sense. Adapters for converting female ends to male, and male ends to female, are readily available (and cheap) and will allow you to custom tailor the cabling exactly as you need it. It's just like laying model train track.

If you want to daisy-chain using a Y-adapter, you can simply plug one outgoing branch of the Y-adapter directly into the input of one of the subs and run a cable to the next sub off the other branch. That leaves the adapter dangling off the back of one sub. If this is not desirable, you can simply add a short cable between the adapter and that sub.

"All men are frauds. The only difference between them is that some admit it. I myself deny it."
sivadselim is offline  
Sponsored Links
Advertisement
 
post #92 of 2083 Old 02-25-2009, 02:38 PM
AVS Addicted Member
 
sivadselim's Avatar
 
Join Date: Oct 2004
Location: CO
Posts: 16,081
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 51 Post(s)
Liked: 68
Regarding the phasing, I think he said (and I paraphrase - perhaps incorrectly) that getting the subs "in phase" was not the goal. Using the phasing to adjust them for the smoothest response is the goal.

"All men are frauds. The only difference between them is that some admit it. I myself deny it."
sivadselim is offline  
post #93 of 2083 Old 02-25-2009, 02:40 PM
AVS Club Gold
 
craig john's Avatar
 
Join Date: Oct 2003
Location: Lancaster, PA
Posts: 10,287
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 66 Post(s)
Liked: 311
Quote:
Originally Posted by Randybes View Post

You may have a point (on below 20Hz-I am not sure that is super important to him)... but we listened (and watched) the recent Cream DVD at very loud levels. Jack Bruce was pretty much there in the room as far as I could tell.

I doubt Bruce's guitar had much below 40 Hz, (unless he's switched to a 5-string bass guitar.) Therefore, a 3-sub system with even moderate subs should *easily* reproduce 40 Hz and up.

Quote:
Originally Posted by Randybes View Post

My priority is working toward the smooth transitions mentioned above and less seat to seat variation. I have heard the rotary sub twice and while it is interesting, I am not going for detecting structural weakness in my home.

Have you tried Audyssey MultEQ XT?

Multiple subs + Room Treatments + Audyssey = Bass Nirvana (IME)

Craig

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

My System

craig john is offline  
post #94 of 2083 Old 02-25-2009, 02:44 PM - Thread Starter
AVS Special Member
 
Randybes's Avatar
 
Join Date: May 2002
Location: Midwest
Posts: 2,622
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by craig john View Post

I doubt Bruce's guitar had much below 40 Hz, (unless he's switched to a 5-string bass guitar.) Therefore, a 3-sub system with even moderate subs should *easily* reproduce 40 Hz and up.


Have you tried Audyssey MultEQ XT?

Multiple subs + Room Treatments + Audyssey = Bass Nirvana (IME)

Craig

I have the Pro Audyssey and have the installer kit. I have been to their "training" and their demos. I have room treatments and I think Audyssey does a nice job but doesn't lend itself IMO to Earl's main speaker approach. I also do agree with Floyd Toole that there really is going to be one best seat and that to equalize above the transition isn't always going to improve the sweet spot and may make it worse.

I have not however, put the Audyssey back into the system and used it only for subs. I do intend to experiment with that but it introduces quite a lot of latency into the system. That being said, I am going to test it out. I am a little leery of how I will fare trying to get good integration with Eerl's (Abbey 12) mains and center, running them full range, and using the Audyssey only for the subs. Suggestions?

One of the benefits of Earl's speakers and sub approach is the incredible dynamic range that results.
Randybes is offline  
post #95 of 2083 Old 02-25-2009, 02:54 PM
Senior Member
 
pjpoes's Avatar
 
Join Date: Feb 2007
Posts: 309
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Getting them in phase and getting the smoothest response is really the same thing.

Dr. Geddes already mentioned that he feels measurements are paramount to doing this right. If you can do it by ear, then great, I can't. Measurements are easy to do and immensely helpful.

THX reference levels, as I mentioned earlier, is 30hz to 80hz, right? at greater than 115db's. With that in mind, Dr. Geddes recommended subs would achieve that. Having said that, he started his comments in this thread by saying, he doesn't care what you use for subwoofers, as long as you have at least 3 and with varied Q's.

My take from our conversations and his posts is that this could be achieved in any number of ways. If you bought three identical subs (For instance), that were all ported like SVS does, where you can vary the tuning by plugging ports, just plug different numbers of ports, and you have achieved this. If you have one sealed sub, one ported sub, and a different sized sealed sub, you would achieve this goal. Even three identical subs spread around the room will be better than one.
pjpoes is offline  
post #96 of 2083 Old 02-25-2009, 03:06 PM
AVS Club Gold
 
craig john's Avatar
 
Join Date: Oct 2003
Location: Lancaster, PA
Posts: 10,287
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 66 Post(s)
Liked: 311
Quote:
Originally Posted by Randybes View Post

I have the Pro Audyssey and have the installer kit. I have been to their "training" and their demos. I have room treatments and I think Audyssey does a nice job but doesn't lend itself IMO to Earl's main speaker approach. I also do agree with Floyd Toole that there really is going to be one best seat and that to equalize above the transition isn't always going to improve the sweet spot and may make it worse.

I don't understand "equalize above the transition". Transition to what?

Quote:
Originally Posted by Randybes View Post

I have not however, put the Audyssey back into the system and used it only for subs. I do intend to experiment with that but it introduces quite a lot of latency into the system. That being said, I am going to test it out. I am a little leery of how I will fare trying to get good integration with Eerl's (Abbey 12) mains and center, running them full range, and using the Audyssey only for the subs. Suggestions?

I don't know how you would use the Pro version to *only* EQ the subs. If you want to do that, I would suggest getting the SVS AS-EQ1, which is an Audyssey product specifically for the purpose of EQ'ing the subwoofer(s):
http://www.svsound.com/products-parts-subeq.cfm

Quote:
Originally Posted by Randybes View Post

One of the benefits of Earl's speakers and sub approach is the incredible dynamic range that results.

I've never heard Dr. Geddes's speakers, but I understand he uses high-sensitivity, "pro" drivers, with waveguides for high directivity. I appreciate this approach and I would expect his speakers to sound excellent.

Craig

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

My System

craig john is offline  
post #97 of 2083 Old 02-25-2009, 03:26 PM
Senior Member
 
pjpoes's Avatar
 
Join Date: Feb 2007
Posts: 309
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10

Here is one of my subwoofers, it had a single band parametric eq which I used to get the flatest response I could, with just the one band. This is averaged across 4 listening positions, which really are quite close to each other.


Here is with three subs and the mains going. Averaged across the same three locations. I've not spent a lot of time positioning the subs, playing with the eq's, or even adjusting the phase. I've taken measurements and done some basic tweaking to get to this point. That's really about it.


This is the overall system response from my primary listening position with the speakers turned about 90 degrees, but not spatially averaged. It was done a while back, so it's possible I've done sub tweaking since then that would further enhance the response. There is no gating, so plenty of room in there.

The room is largely not treated. I have 4 panels which are 4" thick, 2 panels which are 6" thick and open back in a corner (bass trap), and a few 2" panels around the room as well. The only other things at the moment probably have no impact on bass. I do plan on building some broad band panel traps to see if I can't add some dampening, since I don't personally have the option of constrained layer walls.
pjpoes is offline  
post #98 of 2083 Old 02-25-2009, 03:54 PM
Senior Member
 
pjpoes's Avatar
 
Join Date: Feb 2007
Posts: 309
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10

Those other graphs were not smoothed at all. Here are 1/6th smoothed taken at one location, no averaging, 1 sub vs 3 subs. Also keep in mind that my sub placements don't match Dr. Geddes recommendations yet, as one of my subwoofers is just too heavy, and I've not had help or taken the time yet. I think it's pretty telling the advantage of 3 vs 1, and no eq can fix those problems. Also note that there is a gain in output, which looks all the more impressive given how much more energy there is in the 40-100hz area.
pjpoes is offline  
post #99 of 2083 Old 02-25-2009, 04:44 PM
AVS Special Member
 
sean_w_smith's Avatar
 
Join Date: Jan 2005
Location: Los Altos, CA and Huntsville, UT
Posts: 4,292
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Quote:
Originally Posted by gedlee View Post

EQ should be thought of as the exception, not the norm. As Randy points out the bass in my room - WITH NO EQ! - is the best that he's heard. Based on that how can you say that its necessary?

not downplaying the importance of placement and that multiple subs can smooth out the response but:

Lets see some graphs... I have not seen a room yet that would not benefit from EQ and treatments....

Sean
sean_w_smith is offline  
post #100 of 2083 Old 02-25-2009, 04:48 PM
AVS Addicted Member
 
sivadselim's Avatar
 
Join Date: Oct 2004
Location: CO
Posts: 16,081
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 51 Post(s)
Liked: 68
Quote:
Originally Posted by sean_w_smith View Post

not downplaying the importance of placement and that multiple subs can smooth out the response but:

Lets see some graphs... I have not seen a room yet that would not benefit from EQ and treatments....

His room is definitely treated. Which is why EQ may not be necessary. But the whole point of his method is that with 3 subs, properly chosen, properly placed, and properly adjusted, you can achieve what you want to achieve in ANY room.

"All men are frauds. The only difference between them is that some admit it. I myself deny it."
sivadselim is offline  
post #101 of 2083 Old 02-25-2009, 04:53 PM
AVS Special Member
 
sean_w_smith's Avatar
 
Join Date: Jan 2005
Location: Los Altos, CA and Huntsville, UT
Posts: 4,292
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Quote:
Originally Posted by sivadselim View Post

His room is definitely treated. Which is why EQ may not be necessary. But the whole point of his method is that with 3 subs, properly placed and adjusted, you can achieve what you want to achieve in ANY room.

I have tons of treatment in my room and it helps but it still needs Eq.

sounds great in theory, I want to see the objective results....

Sean
sean_w_smith is offline  
post #102 of 2083 Old 02-25-2009, 04:57 PM
Senior Member
 
pjpoes's Avatar
 
Join Date: Feb 2007
Posts: 309
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
what's wrong with mine? It still shows objectively what multiple subs does to room modes. The measurements are rough, but for the plain purpose of seeing how multiple subs can improve the room's response by getting rid of the roughness. What about Markus, his website also shows improvements from it with measurements. Over the weekend I will work on taking proper measurements in the same way I took the full range ones to get a more accurate representation of the response, since that rising towards 150hz isn't accurate. None the less, the peaks and nulls caused by room modes are real, and showed up in the response, which was my main objective.
pjpoes is offline  
post #103 of 2083 Old 02-25-2009, 05:21 PM
AVS Special Member
 
Ironmike86's Avatar
 
Join Date: Nov 2005
Location: Washington 98047
Posts: 1,710
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by penngray View Post

People posting "Best they heard" without proof is meaningless because of obvious BIAS during the experience.

The only way to confirm if its good is to post the measurements!

Exactly. Measurments help but it maynot show everything? But it reminds me of the drunk guy who just met the most "beautiful girl in the world"
Say the responce is really good with multiple "cheap" subs. The measurments aren't going to show the SQ on the subs? Would the more expensive one with the better driver and build quality sound better than multiple subs with less quality of drivers? That would make me want the one expensive sub. Treatments aren't going to make the sub sound better or is it? Just fix the responce?
Ironmike86 is offline  
post #104 of 2083 Old 02-25-2009, 05:32 PM
AVS Special Member
 
sean_w_smith's Avatar
 
Join Date: Jan 2005
Location: Los Altos, CA and Huntsville, UT
Posts: 4,292
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Quote:
Originally Posted by pjpoes View Post

what's wrong with mine? It still shows objectively what multiple subs does to room modes. The measurements are rough, but for the plain purpose of seeing how multiple subs can improve the room's response by getting rid of the roughness. What about Markus, his website also shows improvements from it with measurements. Over the weekend I will work on taking proper measurements in the same way I took the full range ones to get a more accurate representation of the response, since that rising towards 150hz isn't accurate. None the less, the peaks and nulls caused by room modes are real, and showed up in the response, which was my main objective.

agreed but that response could still be improved with some eq.... its far from the flattest in room response I've seen for multiple subs and not as good as what my friend mfine is getting in his room with good placement, treatments and eq with a single sub (seaton submersive).

Sean
sean_w_smith is offline  
post #105 of 2083 Old 02-25-2009, 05:40 PM
Senior Member
 
gedlee's Avatar
 
Join Date: Dec 2008
Posts: 342
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 23
Wow a lot was covered - more than I can addreess, but here is one that you guys may be able to address: I don't get notices of posts from this site. I've complained about this at least three times now, but nothing changes. I get a few, then nothing. I am unaware that anyone is posting anything - I miss it all.

As to the AVS forum and my presence, well that was absurd to begin with and I hope that the accusations stay away. There are lots of other things to do in the world than sit at a computer.

Yes, EQ can always be an improvement - but is never the solution! Eq can be the icing on the cake, get the last few dB of improvement, but it can never achieve what multiple sources achieves.

And I said early on that I didn't want to get into a game of "what sub is best" because that is pretty much irrelavent to me. Its not my subs and its not my room that makes the difference its the approach. It works in any room with any subs. Thats the point and all the other details are not of much concern to me.

Well back to the Redwings game!

Earl R. Geddes
GedLee
gedlee is offline  
post #106 of 2083 Old 02-25-2009, 05:54 PM - Thread Starter
AVS Special Member
 
Randybes's Avatar
 
Join Date: May 2002
Location: Midwest
Posts: 2,622
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by craig john View Post

I don't understand "equalize above the transition". Transition to what?



Craig

Transition from the effects of the room to the speaker. It is a term you will find in Floyd Tooles writings and CEDIA courses. Below the transition frequency the room dominates above the speaker dominates. Obviously, it is not a brick wall thing. I already am on the SVS eq pre order but I don't know how you would integrate more than two subs. I have asked that question in the thread but the answer seems to be you can't even if you buy two. Chris said you could use the pro just to equalize the subs-up to seven if you want.

I would be interested in audtioning your room if that is something you could accomodate.
Randybes is offline  
post #107 of 2083 Old 02-25-2009, 05:56 PM
AVS Special Member
 
Ironmike86's Avatar
 
Join Date: Nov 2005
Location: Washington 98047
Posts: 1,710
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
I agree with your approah multiple subs and treatments will sound good. But the post is "3 cheaper subs better than 1 expensive sub" . I have 3 subs that co$t @ $1600. In a small-med. Room. I would rather have one $1600 sub which should be of better quality.
Sounds good to me. But I would think the better sub would have better SQ . I will be able to graph them next week to see what I'm hearing or missing.
Ironmike86 is offline  
post #108 of 2083 Old 02-25-2009, 06:05 PM
Member
 
nwbnd's Avatar
 
Join Date: Oct 2007
Location: Grand Haven, MI
Posts: 57
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I don't have much to contribute other than to ask why this hasn't surfaced in this discussion yet?

www.harman.com/wp/pdf/multsubs.pdf

I assume most if not all of the people who would read this thread would have stumbled across this already.

I'll go back to my seat now
nwbnd is offline  
post #109 of 2083 Old 02-25-2009, 06:09 PM - Thread Starter
AVS Special Member
 
Randybes's Avatar
 
Join Date: May 2002
Location: Midwest
Posts: 2,622
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by nwbnd View Post

I don't have much to contribute other than to ask why this hasn't surfaced in this discussion yet?

www.harman.com/wp/pdf/multsubs.pdf

I assume most if not all of the people who would read this thread would have stumbled across this already.

I'll go back to my seat now

Over on the DIY thread you will find posts by Todd Welti and Dr. Geddes on Todd's Harmon study. Some back and forth that is interesting. I linked it in an earlier post.
Randybes is offline  
post #110 of 2083 Old 02-25-2009, 06:11 PM - Thread Starter
AVS Special Member
 
Randybes's Avatar
 
Join Date: May 2002
Location: Midwest
Posts: 2,622
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by Ironmike86 View Post

I agree with your approah multiple subs and treatments will sound good. But the post is "3 cheaper subs better than 1 expensive sub" . I have 3 subs that co$t @ $1600. In a small-med. Room. I would rather have one $1600 sub which should be of better quality.
Sounds good to me. But I would think the better sub would have better SQ . I will be able to graph them next week to see what I'm hearing or missing.

I would encourage you to show measurements of more than one position averaged. While one position may show great response, the idea is to get a smooth response over a wider area.
Randybes is offline  
post #111 of 2083 Old 02-25-2009, 06:14 PM
AVS Special Member
 
goonstopher's Avatar
 
Join Date: Dec 2008
Location: NJ near NYC
Posts: 4,169
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Well another thing to consider... what about adding another sub VS adding a good EQ like SVS's new Audyssey product appears to be.
goonstopher is offline  
post #112 of 2083 Old 02-25-2009, 06:18 PM - Thread Starter
AVS Special Member
 
Randybes's Avatar
 
Join Date: May 2002
Location: Midwest
Posts: 2,622
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by Ironmike86 View Post

I agree with your approah multiple subs and treatments will sound good. But the post is "3 cheaper subs better than 1 expensive sub" . I have 3 subs that co$t @ $1600. In a small-med. Room. I would rather have one $1600 sub which should be of better quality.
Sounds good to me. But I would think the better sub would have better SQ . I will be able to graph them next week to see what I'm hearing or missing.

You have hit on the controversy in my mind. What determines great bass SQ in a room. I think the argument is that you don't need mega expensive subs to get great sound quality and that one sub won't cut it no matter how great it is. After that, if you want to have several great subs that go down to the sub sub frequencies, go for it.

I think it is controversial among people who are really "into" various brands of subs (and why Earl is not). I think it is less controversial among the Welti's, Floyds and Geddes of the world. I would guess that if we could get Todd Welti over to AVS again, he would disagree with Earl on certain issues, but not on what is better one great sub or 4 lesser subs in his recommended configuration.

Anyone who wants to invite him from the DIY thread (or the one that was in the Audio Theory section) is welcome as I love these threada were the experts participate. He seems like a great guy. I just want the focus to be one great sub against three (or four or five) lesser subs.
Randybes is offline  
post #113 of 2083 Old 02-25-2009, 06:24 PM
Senior Member
 
gedlee's Avatar
 
Join Date: Dec 2008
Posts: 342
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 23
Todd Welti (JBL) and I agree far more than we disagree. We both believe in multiple subs, but we set them up differently. His work is a must read, but you should remember that there are others ways to setup the subs than the JBL SFM approach. Mine is simpler and less expensive, but Todds, admittedly, is probably more comprehensive. But at some point enough is enough and I feel that the simpler approach IS enough. The more ellaborate calculations don't buy you enough to be worth the cost. But if "cool" boxes, hi-powered subs and mega-bucks expense is what you want then go for the JBL stuff. I'm perfectly content with what I have. It works well as all who have heard it will testify to.

Earl R. Geddes
GedLee
gedlee is offline  
post #114 of 2083 Old 02-25-2009, 06:27 PM
AVS Addicted Member
 
sivadselim's Avatar
 
Join Date: Oct 2004
Location: CO
Posts: 16,081
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 51 Post(s)
Liked: 68
Quote:
Originally Posted by gedlee View Post

And I said early on that I didn't want to get into a game of "what sub is best" because that is pretty much irrelavent to me. Its not my subs and its not my room that makes the difference its the approach. It works in any room with any subs. Thats the point and all the other details are not of much concern to me.

Is it "bears" repeating or "bares" repeating?

"All men are frauds. The only difference between them is that some admit it. I myself deny it."
sivadselim is offline  
post #115 of 2083 Old 02-25-2009, 06:39 PM - Thread Starter
AVS Special Member
 
Randybes's Avatar
 
Join Date: May 2002
Location: Midwest
Posts: 2,622
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by Ironmike86 View Post

Exactly. Measurments help but it maynot show everything? But it reminds me of the drunk guy who just met the most "beautiful girl in the world"
Say the responce is really good with multiple "cheap" subs. The measurments aren't going to show the SQ on the subs? Would the more expensive one with the better driver and build quality sound better than multiple subs with less quality of drivers? That would make me want the one expensive sub. Treatments aren't going to make the sub sound better or is it? Just fix the responce?

I am not sure I understand this post. Or you saying dismiss subjective reports ("Exactly") or that measurements don't tell you about SQ?
Randybes is offline  
post #116 of 2083 Old 02-25-2009, 07:00 PM - Thread Starter
AVS Special Member
 
Randybes's Avatar
 
Join Date: May 2002
Location: Midwest
Posts: 2,622
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by sean_w_smith View Post

agreed but that response could still be improved with some eq.... its far from the flattest in room response I've seen for multiple subs and not as good as what my friend mfine is getting in his room with good placement, treatments and eq with a single sub (seaton submersive).

Sean

One position or more than one position? We need to make sure we are comparing apples to apples and not one position maximized for best response for that measurement microphone (not to mention smoothing and a bunch of other things I don't even understand). Where is Mark in this thread? I know he has exchanged some posts with Earl in the DIY forum.
Randybes is offline  
post #117 of 2083 Old 02-25-2009, 07:11 PM
AVS Special Member
 
MUCHO's Avatar
 
Join Date: Sep 2005
Location: Southern California
Posts: 1,147
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
You guys know much more than me about this but it seems like the expensive part comes from powerful amplifiers and drivers that allow big time output and subsonic frequency reproduction.

If you're only concerned with 25hz and above with reasonable SPL it there are plenty of reasonably priced subwoofers are the market that have great sound quality.

It seems obvious to me that given you are only concerned with 25hz and above then of course three inexpensive subwoofers (with good SQ) would be superior to 1 expensive one.

If you want to have your SPL and subsonic reproduction then you need to spend more.

Right?
MUCHO is offline  
post #118 of 2083 Old 02-25-2009, 07:17 PM - Thread Starter
AVS Special Member
 
Randybes's Avatar
 
Join Date: May 2002
Location: Midwest
Posts: 2,622
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by MUCHO View Post

You guys know much more than me about this but it seems like the expensive part comes from powerful amplifiers and drivers that allow big time output and subsonic frequency reproduction.

If you're only concerned with 25hz and above with reasonable SPL it there are plenty of reasonably priced subwoofers are the market that have great sound quality.

It seems obvious to me that given you are only concerned with 25hz and above then of course three inexpensive subwoofers (with good SQ) would be superior to 1 expensive one.

If you want to have your SPL and subsonic reproduction then you need to spend more.

Right?

Well that is part of it, but the other part is what is important for good bass in a small room. It has much to do with modes, nulls, and other such important things. Put the greatest sub in the world in a small room, and listen in a null while your audiophile friend listens in a peak. You will be saying this sub sucks no bass and your friend will say turn it down, boomy and too much bass. I will give some kudos to Sencore. I went to their academy training and we put a sub in the room and walked the room. There where places were there was basically no bass and others (like boundaries) where the bass was boomy as hell. It would not make any difference if the sub was cheap or expensive with bass to the depths of the depths.

One thing I did learn from my HAA training is how small changes in position of both the sub and the seat make SO much difference. Multiple subs helps to reduce that problem. Those here that know mutilple subs are the way to go need to then move on to setup. Do you use Dr. Geddes approach described in the linked threads or some variable of Harmons approach. Advantage to Geddes approach is the ability to use different brand subs (actually encouraged) some additional flexibility of placement of the subs. Finally, the fact that it is for the most part not dependent on expensive boxes. That IMO is why his approach is appealing. I will say he does live by his creed. He uses science to try to find the best most economical approach that matters. His $30 HT transparent sheet that I could not tell any difference from a normal expensive screen is another thread in another area!
Randybes is offline  
post #119 of 2083 Old 02-25-2009, 07:32 PM
AVS Addicted Member
 
sivadselim's Avatar
 
Join Date: Oct 2004
Location: CO
Posts: 16,081
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 51 Post(s)
Liked: 68
Quote:
Originally Posted by MUCHO View Post

If you want to have your SPL and subsonic reproduction then you need to spend more.

How much you want to spend is up to you but, as pointed out, there is no reason you can go down into the teens (or lower) with the method presented here, if you do it correctly. How about a PB13U and 2 additional subs (2 SB12+s, for example)?

"All men are frauds. The only difference between them is that some admit it. I myself deny it."
sivadselim is offline  
post #120 of 2083 Old 02-25-2009, 07:35 PM
Senior Member
 
pjpoes's Avatar
 
Join Date: Feb 2007
Posts: 309
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Yeah sorry I mis-wrote what that last measurement was. It's all multiple positions, but some of them were spatially averaged, the last one was an average of non-spatially averaged responses taken at the various locations, comparing one to two.

Also, a lot of people measure their subwoofers in ways that minimize the room's effect, you can't do that if you want to talk about this method. If we were to compare different peoples responses, it has to be measured in the same fashion. None the less, something was wrong when I quickly took those measurements, and I didn't have time to futz around until it was right. My main goal was simply to show how the multiple subs can remove those effects of the room modes.
pjpoes 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