Theory behind Dunlavy and Lipinski speakers? - 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 17th November 2005, 04:46 AM   #1
azrix is offline azrix  United States
diyAudio Member
 
Join Date: Oct 2004
Default Theory behind Dunlavy and Lipinski speakers?

I've read quite a bit about Dunlavy's and now Lipinski's being used in studios. I think I understand about the WMTMW design, it being very similiar to the idea of the MTM D'Appolito arrangement. I also understand about Dunlavy using first order crossovers. I understand about using sealed enclosures. What I definitely don't understand is their use of felt and foam around the tweeter in particular. Is it purely a way of trying to reduce diffraction or is there some kind of horn loading of these designs or something else? I'd like to know. I can not recall seeing any discussion about it online. Anyone?
  Reply With Quote
Old 17th November 2005, 05:22 AM   #2
diyAudio Member
 
Join Date: Oct 2004
Default Re: Theory behind Dunlavy and Lipinski speakers?

Quote:
Originally posted by azrix
Is it purely a way of trying to reduce diffraction?
This is what it is if I'm not completely mistaken. No horn loading or anything like that.
  Reply With Quote
Old 17th November 2005, 07:26 AM   #3
diyAudio Member
 
Join Date: Aug 2003
Location: Santa Cruz, California
Note the tweeter is inset from the mids. That helps time alignment, which is fairly critical with first order crossovers. It also means you need to keep side radiation from the tweeter from bouncing around the cabinet walls, hence another reason for the felt.


Cheers,
Francois.
  Reply With Quote
Old 17th November 2005, 09:37 AM   #4
diyAudio Member
 
David Gatti's Avatar
 
Join Date: Mar 2004
Location: Melbourne, Australia
I've read John Dunlavy's white papers on his design principles.
Dunlavy (and Duntech) speakers have stepped baffles, which in conjuction with the first order filters, create a linear phase response. i.e the waveform shape is preserved. Because of the steps in the baffle, severe diffraction would occur, and so heavy felt damping is applied to absorb the sound waves before they hit the edges. It also reduces diffraction with the sides of the baffle.

Take a look at www.duntech.com.au , the company John Dunlavy founded a few decades ago in Australia, and is still operating.
Also see http://www.vaf.com.au who use a similar principle.
  Reply With Quote
Old 17th November 2005, 12:22 PM   #5
diyAudio Member
 
Join Date: Oct 2004
Quote:
Originally posted by DSP_Geek
Note the tweeter is inset from the mids. That helps time alignment, which is fairly critical with first order crossovers.
Yes, some guys at my university were building Duntech-clones and explained the reason for the inset.

How can one analyze the time alignment of crossovers/drivers?
  Reply With Quote
Old 17th November 2005, 01:53 PM   #6
f4ier is offline f4ier  Australia
diyAudio Member
 
f4ier's Avatar
 
Join Date: Sep 2001
Location: Sydney
Landroval, John Kreskovsky has papers in his website regarding the subject.

Shame that Dunlavy Audio Labs went belly-up. I wonder if Dunlavy is still active (in)directly at Duntech. Those Sovereigns must really sound good. Boy I'd like to hear Telarc's Stokowski Sound CD-80129 through a pair of those
__________________
Crossover/Subwoofer Simulator
  Reply With Quote
Old 18th November 2005, 12:53 AM   #7
mike.e is offline mike.e  New Zealand
diyAudio Member
 
mike.e's Avatar
 
Join Date: Sep 2004
Location: NZ
Send a message via ICQ to mike.e Send a message via MSN to mike.e
Quote:
Originally posted by Landroval


Yes, some guys at my university were building Duntech-clones and explained the reason for the inset.

How can one analyze the time alignment of crossovers/drivers?

You can analyse it in the time domain using COOLEDIT 2000 or similar with added functions. Its the acoustical response we are after. But what happens once we are in room?


Click the image to open in full size.

http://db.audioasylum.com/cgi/m.mpl?forum=hug&n=82145
http://www.triodefestival.net/member...vers_etf04.zip
  Reply With Quote
Old 18th November 2005, 04:24 AM   #8
azrix is offline azrix  United States
diyAudio Member
 
Join Date: Oct 2004
Thanks everyone. I am aware about the stepped baffles. I remember reading awhile back, before I know much about speakers, where someone implied that there was more to the felt than just diffraction reduction. That's why I asked.

Have any of you messed with felt like this? Given the inset drivers and the shape of the baffle, it seems to me that reducing diffraction would be a monumental task, with felt or without.

f4ier, Dunlavy didn't exactly go "belly up". They were sold to a larger company that was hoping to make more money with speakers by increasing production and/or productivity or something like that. The buyer got Dunlavy and then realized it was cheaper for them to just close down the factory then to put any more money into changing Dunlavy. At least that's what I heard. Dunlavy was a profitable company and didn't go out of busines by going bankrupt, as far as I know.

I found an archive of Dunlavy's newsgroup postings awhile back, here I think: http://home.austin.rr.com/tnulla/ , but it seems to be gone. Does anyone know if it's still up somewhere? Google doesn't bring up any working links for me.
  Reply With Quote
Old 18th November 2005, 09:07 AM   #9
diyAudio Member
 
Join Date: Mar 2004
Location: Jakarta
just to share to may experience...

I audition a system with big Dunlavy speaker with WMTMW...

and at the same time there is a big Tannoy coaxial speaker (wider than the Dunlavy, which is about 2meters tall, and 50cm wide)

and to my amazement... Dunlavy sound a lot better than the Tannoy...

Dunlavy with multiple drivers simply disappear... (just like a single source speaker) and throwing a very spacious soundstage...

---
David
  Reply With Quote
Old 18th November 2005, 07:00 PM   #10
diyAudio Member
 
Join Date: Jul 2003
Location: Silicon Valley
Default Imaging

A friend of mine has a pair of Dunlavy IV/A's. The drivers are good quality Vifa's and such, but hardly remarkable these days. The cabninets are huge. Nevertheless, the "sweet spot" is only about a foot wide! You've got to sit smack in the middle to hear them at their best.
__________________
Davy Jones
  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
Help with dunlavy SM1 crossover ebenai Multi-Way 12 27th December 2008 12:21 AM
WTB: FELT F13 Grey - 1/4" to 3/4" Thick - Like on Duntech/Dunlavy Speakers' Baffle dtm1962 Swap Meet 0 21st October 2006 04:18 AM
Question on the theory/practice of 2/3/4...-way speakers JCDenton Multi-Way 3 6th June 2006 06:13 AM
dunlavy sc-1 maxpou Multi-Way 4 2nd May 2006 11:23 PM
Dunlavy out of business? eLarson Everything Else 0 10th November 2002 01:16 PM


New To Site? Need Help?

All times are GMT. The time now is 02:53 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