Measured monopole and dipole room responses - Page 53 - diyAudio
Go Back   Home > Forums > Loudspeakers > Multi-Way

Multi-Way Conventional loudspeakers with crossovers

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 18th October 2012, 11:05 PM   #521
Elias is offline Elias  Finland
diyAudio Member
 
Elias's Avatar
 
Join Date: May 2003
Location: Where you live
Quote:
Originally Posted by KSTR View Post
Also IRCC, there is a recent peer-reviewed paper on the localisation of bass which showed that freq range might need an update to lower ranges than currently established... I just can't find it anymore.
I think I know what you mean, there was a recent conference in Australia, right ? I've seen that paper too.

It was discussed in diyaudio as well, and some had hard time to believe the results Oh well..
__________________
Liberate yourself from the illusion of two speaker stereo triangle
Dipole Bass vs Monopole Bass Stereophonic Sound from a Single Loudspeaker 3 Speaker Linear Stereo Matrix Wavelets
  Reply With Quote
Old 18th October 2012, 11:06 PM   #522
Elias is offline Elias  Finland
diyAudio Member
 
Elias's Avatar
 
Join Date: May 2003
Location: Where you live
Quote:
Originally Posted by markus76 View Post
That's exactly the problem, you just can't do that within an acoustically small room. You can do it with headphones but why the heck are low frequencies still not externalized? Something is wrong in Griesinger's theory.
To me it looks like only thing wrong is your interpretation on it ?
__________________
Liberate yourself from the illusion of two speaker stereo triangle
Dipole Bass vs Monopole Bass Stereophonic Sound from a Single Loudspeaker 3 Speaker Linear Stereo Matrix Wavelets
  Reply With Quote
Old 18th October 2012, 11:14 PM   #523
ScottG is offline ScottG  United States
diyAudio Member
 
Join Date: Feb 2003
Location: US
Quote:
Originally Posted by Elias View Post
Scott,

Tell us again please why we should listen to that youtube clip ?

Because while listening to it I found out the deepest truth about youtube, the true meaning of it ! It sounds like coming from a tube, literally !




Are you telling you don't get in the head sound if you place a single mono bass speaker 0.5 m behind your head symmetrical to median plane at ear level located in the middle of the room ?


- Elias
That's the way the recording was recorded and intended to sound - as if in a large "tunnel-like" club. (..reminiscent of New Orleans Jazz clubs.)


I've never done that at ear level.. why would you? Under *all the other constraints though and adding proper phase rotation - yes. And the result was not "in the head".

*I'm not sure about the distance, could have been closer to a meter than half a meter.


A setup like you are describing sounds absurd.
__________________
perspective is everything
  Reply With Quote
Old 18th October 2012, 11:25 PM   #524
Elias is offline Elias  Finland
diyAudio Member
 
Elias's Avatar
 
Join Date: May 2003
Location: Where you live
Quote:
Originally Posted by ScottG View Post
I've never done that at ear level.. why would you? Under *all the other constraints though and adding proper phase rotation - yes. And the result was not "in the head".

*I'm not sure about the distance, could have been closer to a meter than half a meter.


A setup like you are describing sounds absurd.

Maybe it is absurd but according to Markus that should be the reference

Quote:
Originally Posted by markus76 View Post
Put a sub directly behind your listening position at shoulder height and get a frame of reference what good low frequency reproduction sounds like.

Ok, he says "shoulder height", not ear, but if one has really short neck it should be about the same
__________________
Liberate yourself from the illusion of two speaker stereo triangle
Dipole Bass vs Monopole Bass Stereophonic Sound from a Single Loudspeaker 3 Speaker Linear Stereo Matrix Wavelets
  Reply With Quote
Old 18th October 2012, 11:36 PM   #525
ScottG is offline ScottG  United States
diyAudio Member
 
Join Date: Feb 2003
Location: US
Quote:
Originally Posted by Elias View Post
Maybe it is absurd but according to Markus that should be the reference

Ok, he says "shoulder height", not ear, but if one has really short neck it should be about the same


Yeah.. that doesn't sound right either.


When I've done a monaural sub like that it's been:

1. (sealed, ported, T-line, and dipole).

2. about a foot away from the listening chair.

3. ON THE FLOOR (and as a result more than a foot away from my head).

4. always required proper adjustment of crossover freq. and full variable phase rotation.

It hasn't always been in the center of the room either, though often closer to center than not and always with at least 4 feet away from any wall.


I'm not even saying that is particularly domestically acceptable. BUT in a larger room it often works out well - at least for that one listener (..and that's all that is required for "critical" listening).



I should also note that I have done stereo sub setups as "side tables" that were closer to my head.
__________________
perspective is everything

Last edited by ScottG; 18th October 2012 at 11:39 PM.
  Reply With Quote
Old 19th October 2012, 01:03 AM   #526
diyAudio Member
 
Join Date: Oct 2010
Location: philadelphia
Hello again,
Seems like we have drifted from the subject line

I was hoping to have some graphs of in-room impulse response from John using Elias's methods and look for reproducibility of the graphs obtained by Elias earlier, that clearly showed superior in-room transient response of dipole compared to sealed.

Or has everybody come to the unstated conclusion that if equalised to the same low end extension, there is no difference in sound quality between a sealed/cardioid/dipole woofer.

On my part, after some more carefully equalised responses of dipole and sealed, feel that they do come quite close. However, even then when crossed as low as 120Hz, I find that dipole woofers blend so seamlessly with dipole mains like magnepan. OTOH a sealed woofer has that slight overhanging sound, carrying them so far away from realism.
  Reply With Quote
Old 19th October 2012, 02:12 AM   #527
gedlee is offline gedlee  United States
diyAudio Member
 
gedlee's Avatar
 
Join Date: Dec 2004
Location: Novi, Michigan
The problem with this thread is the constant retreat to "Well it sounds good to me!" Its simply pointless to have a reasonable discussion when that is done because any side can do it and claim anything that they want (and often do). Unless we are talking about scientifically established facts its just a bunch of unsubstantiated opinions.

There is no established fact that two equal frequency responses will not sound the same. Scientifically I will continue to assume that they do because to assume anything else would be illogical.
  Reply With Quote
Old 19th October 2012, 03:29 AM   #528
diyAudio Member
 
Join Date: Jan 2008
Two identical frequency responses need not sound the same do to temporal characteristics: Exponential swept sine and pink noise have same spectrum over time, and sound totally different. But yes, two equal frequency responses with similar phase properties sound highly similar.
  Reply With Quote
Old 19th October 2012, 06:19 AM   #529
ScottG is offline ScottG  United States
diyAudio Member
 
Join Date: Feb 2003
Location: US
Quote:
Originally Posted by soundaatma View Post
Hello again,
Seems like we have drifted from the subject line

I was hoping to have some graphs of in-room impulse response from John using Elias's methods and look for reproducibility of the graphs obtained by Elias earlier, that clearly showed superior in-room transient response of dipole compared to sealed.

Or has everybody come to the unstated conclusion that if equalised to the same low end extension, there is no difference in sound quality between a sealed/cardioid/dipole woofer.

On my part, after some more carefully equalised responses of dipole and sealed, feel that they do come quite close. However, even then when crossed as low as 120Hz, I find that dipole woofers blend so seamlessly with dipole mains like magnepan. OTOH a sealed woofer has that slight overhanging sound, carrying them so far away from realism.

It's tough to draw any significant distinction between the radiation profile and the net result to the listener.

Each system: sealed/cardiod/dipole - is not identical irrespective of its radiation. (..JohnK's trick "flip a switch" sub setup would get pretty close though.)

Ex. the "slight overhang.." you hear may have something to do with its in-box operation (vs. that of "open baffle"), rather than it's interaction with the room.
__________________
perspective is everything

Last edited by ScottG; 19th October 2012 at 06:37 AM.
  Reply With Quote
Old 19th October 2012, 10:09 AM   #530
Banned
 
Join Date: May 2008
Location: Switzerland
Results for different near field configurations are in:
Comparison of different near field subwoofer configurations

I also did look at monopole/dipole in the far field. The dipoles were placed right next to the mains.


Dual monopole:

Click the image to open in full size.

Click the image to open in full size.


Dual dipole:

Click the image to open in full size.

Click the image to open in full size.



But the best results were achieved with two dipoles in the near field:

Click the image to open in full size.

Click the image to open in full size.

Near field configuration increases sub efficiency by a whopping 10dB.
Modal ringing is minimized.
The specific dipole near field sub required virtually no equalization.
Dual near field subs enlarge the usable listening area. Bass response is virtually the same within an area of 3 seats.

Last edited by markus76; 19th October 2012 at 10:17 AM.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Omnipole, monopole, dipole and...nopole?? terry j Multi-Way 25 1st July 2007 04:28 AM
Getting Dipole bass out of a monopole subwoofer Hara Subwoofers 18 14th July 2006 01:55 AM
Dipole vs monopole, balls or not ... ? Jussi Multi-Way 11 4th May 2006 04:38 PM
DBX vs BSS vs 24/96 for Dipole/Monopole combo..... gavinson Multi-Way 0 29th November 2005 01:07 AM
Dipole speaker with monopole rear firing midbass? GuyPanico Multi-Way 4 12th November 2005 03:49 PM


New To Site? Need Help?

All times are GMT. The time now is 04:32 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2