Cardioid Bass.... yes, very good!! - 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 8th October 2012, 02:13 PM   #1
diyAudio Member
 
gainphile's Avatar
 
Join Date: Dec 2007
Location: Melbourne the sunny city!
Lightbulb Cardioid Bass.... yes, very good!!

I have been very much appealed to the discussions around Cardioid Bass. More complex to design than dipoles, yet they seem to promise good things when compared to monopoles or dipoles:

1) Least affected to room positioning
http://www.wvier.de/texte/Beneficial...20Coupling.pdf

2) Able to pressurise the room
www.diyaudio.com/forums/multi-way/145876-measured-monopole-dipole-room-responses-13.html#post3188523

3) I had a listen to Musikelectronic Geithain 901K


A W-Frame dipole can be converted to Cardiod quite easily by sealing one of the woofer and equalise accordingly.

DIPOLE Setup:

Click the image to open in full size.


CARDIOID Setup:

Click the image to open in full size.


Equalised response to meet 20hz, Q=0.5 target.

Note: NO LOWPASS XO in this graph.

Click the image to open in full size.


I will need a good day and spare time to get outside polar measurements but a quick listen at the back of the speakers is quite revealing.


The Cardioids have punchy bass, something I miss when listening to dipoles. I'ts also as articulate.

In short, I like it !!
__________________
http://gainphile.blogspot.com

Last edited by gainphile; 8th October 2012 at 11:40 PM.
  Reply With Quote
Old 8th October 2012, 02:37 PM   #2
Banned
 
Join Date: May 2008
Location: Switzerland
Did you also measure the in-room response around the listening position for both configurations?
  Reply With Quote
Old 8th October 2012, 02:41 PM   #3
diyAudio Member
 
john k...'s Avatar
 
Join Date: Aug 2004
Location: US
By sealing one woofer of the W frame you end up with a monopole and a dipole. This alone does not sum to yield a cardioid. The dipole and monopole must be individually equalized to have the same axial response. From you post it is not apparent when you talk about Eqing to meet your target is that is what you did.

But, as you know, I've been on the cardioid wagon since the infroduction of the NaO 10 teas ago.

[edit] Additionally, to get it "perfect" with that apporach the AC of the monopole must be at the axial center of the dipole.
__________________
John k.... Music and Design NaO Dipole Loudspeakers.

Last edited by john k...; 8th October 2012 at 02:44 PM.
  Reply With Quote
Old 8th October 2012, 02:46 PM   #4
diyAudio Member
 
Join Date: Sep 2010
What's with the massive peaks at 600/1200/2400 hz? Cavity resonance? Mind showing the effect of stuffing the dipole section a bit with a thin layer of fibreglass?
  Reply With Quote
Old 8th October 2012, 05:46 PM   #5
Draki is online now Draki  Macedonia
diyAudio Member
 
Join Date: Sep 2010
Question, hopefully not OT: what is the rule (formula) for the bass drivers which can be used horizontally?
  Reply With Quote
Old 8th October 2012, 05:56 PM   #6
DrDyna is online now DrDyna  United States
diyAudio Member
 
DrDyna's Avatar
 
Join Date: May 2007
Blog Entries: 3
Quote:
Originally Posted by Draki View Post
Question, hopefully not OT: what is the rule (formula) for the bass drivers which can be used horizontally?
Sag percentage, it's like...3% or less? something like that.

Edit: It's 5%.
__________________
The best video in the world.

Last edited by DrDyna; 8th October 2012 at 05:59 PM.
  Reply With Quote
Old 8th October 2012, 06:02 PM   #7
DrDyna is online now DrDyna  United States
diyAudio Member
 
DrDyna's Avatar
 
Join Date: May 2007
Blog Entries: 3
Gainphile, what speaker is that? It's gorgeous.

Edit: Found it on your site.
__________________
The best video in the world.

Last edited by DrDyna; 8th October 2012 at 06:09 PM.
  Reply With Quote
Old 8th October 2012, 10:40 PM   #8
Draki is online now Draki  Macedonia
diyAudio Member
 
Join Date: Sep 2010
Quote:
Originally Posted by DrDyna View Post
Sag percentage, it's like...3% or less? something like that.

Edit: It's 5%.

Thanks DrDyna, in the meantime found this : Parts Express - Subwoofer Qualification Formulae For Downfiring Configurations

Turned to be 2,7% so guess OK for up-down mounting.
  Reply With Quote
Old 8th October 2012, 11:16 PM   #9
tinitus is offline tinitus  Europe
diyAudio Moderator R.I.P.
 
Join Date: Nov 2005
I would never do that

though it is said that a woofer is more happy moving out than in
interesting to know if playing up would help it
  Reply With Quote
Old 8th October 2012, 11:36 PM   #10
diyAudio Member
 
Join Date: Jun 2004
Location: Orlando, FLA
Thanks for the post Gain! At what distance was your measurement taken? Am I correct in assuming that the measurement was taken down low in front of the woofers and that's why the mids and highs look so off?

I am going to experiment with trying to get more of a cardioid response from my woofer too. I've been using the Bonded Logic behind the Neo10s , but want to try several layers behind and around the woofer now too. I think JohnK is going to redo his testing of the monopole, dipole and cardioid woofers and send the info to Elias to put through his wavelet app. Have you been reading that thread?

Greg
  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
2-way: Waveguide + Cardioid-like keyser Multi-Way 147 11th August 2014 12:13 AM
Adventures in cardioid MBK Multi-Way 121 15th October 2012 12:44 PM
Cardioid Bass CLS Multi-Way 312 4th May 2012 08:46 PM
Cardioid with a TH sub FlipC Subwoofers 23 4th February 2012 08:03 PM


New To Site? Need Help?

All times are GMT. The time now is 12:52 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