vifa logic x-0ver - 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 28th December 2014, 05:29 AM   #1
ton def is offline ton def  United States
diyAudio Member
 
Join Date: Jun 2014
Default vifa logic x-0ver

I have the vifa logic BC14SG49-4 and AC25SG05-4. I was going to attempt to replicate the Madisound swifty speaker kit. But the kit used the 8 ohm version of the midwoofer. The differences seem to be too much to try and re configure the kits x-over. I found an x-over for these drivers. But it seems odd to me. It appears to have no damping for the tweeter. There is a 7db difference in spl between the woofer and tweeter.
http://www.chyna.wz.cz/audio/index.htmlWill this work ?

Last edited by ton def; 28th December 2014 at 06:11 AM. Reason: info
  Reply With Quote
Old 28th December 2014, 08:03 PM   #2
ton def is offline ton def  United States
diyAudio Member
 
Join Date: Jun 2014
anybody ?
  Reply With Quote
Old 28th December 2014, 08:35 PM   #3
blue934 is offline blue934  Canada
diyAudio Member
 
blue934's Avatar
 
Join Date: Mar 2007
Location: Salmon Arm, B.C.
Not too sure about that xo in link. The phase seems way off and you're right, there's no tweeter attenuation although a 5-10ohm resister in line before the HP filter would be a simple starting point.

As far as the swifty goes, Just cut the inductor in half and double the cap on the woofer circuit to accept the 4ohm model and it should be very close.

David
  Reply With Quote
Old 28th December 2014, 08:45 PM   #4
Sonce is offline Sonce  Macedonia
diyAudio Member
 
Join Date: Jan 2014
Location: Macedonia
C2051 attenuate the tweeter. Crossover seems to be OK.

EDIT: hmm... on the second look, "position" and "relative distance" are 0 mm both for the midbass and the tweeter. Maybe simulation is not the correct one, regarding the actual position of the drivers.

Last edited by Sonce; 28th December 2014 at 08:55 PM.
  Reply With Quote
Old 28th December 2014, 08:49 PM   #5
Sonce is offline Sonce  Macedonia
diyAudio Member
 
Join Date: Jan 2014
Location: Macedonia
Quote:
Originally Posted by blue934 View Post
there's no tweeter attenuation although a 5-10ohm resister in line before the HP filter would be a simple starting point.
David
Are we looking at the same crossover schematic?
This is the one:
www.chyna.wz.cz/audio/efekty/vyhybka.png
  Reply With Quote
Old 28th December 2014, 09:20 PM   #6
ton def is offline ton def  United States
diyAudio Member
 
Join Date: Jun 2014
Quote:
Originally Posted by Sonce View Post
Are we looking at the same crossover schematic?
This is the one:
www.chyna.wz.cz/audio/efekty/vyhybka.png
Yes that is it. But I can't figure out what he is doing. Though he does appear to know what he is doing ?
  Reply With Quote
Old 28th December 2014, 09:43 PM   #7
blue934 is offline blue934  Canada
diyAudio Member
 
blue934's Avatar
 
Join Date: Mar 2007
Location: Salmon Arm, B.C.
Yes, that's the one I was looking at. I've not seen a parallel cap used for attenuation before but if it works, I stand corrected.


David
  Reply With Quote
Old 28th December 2014, 10:07 PM   #8
diyAudio Member
 
Join Date: Feb 2002
Location: Western Sydney
great way to fry an amp, use a proper L pad: L pad calculator - attenuation dB damping impedance decibel loudspeaker speaker voltage divider - sengpielaudio Sengpiel Berlin
__________________
Impedance varies with frequency, use impedance plots of your drivers and make crossover calculations using the actual impedance of the driver at the crossover frequency
  Reply With Quote
Old 28th December 2014, 10:49 PM   #9
ton def is offline ton def  United States
diyAudio Member
 
Join Date: Jun 2014
http://www.madisound.com/pdf/swifty.pdf Yes, I can not understand why he would do the attenuation that way. It just seems unnecessarily complex and costly.But this x-over looks to be less complex than the swifty x-over.
  Reply With Quote
Old 28th December 2014, 11:04 PM   #10
blue934 is offline blue934  Canada
diyAudio Member
 
blue934's Avatar
 
Join Date: Mar 2007
Location: Salmon Arm, B.C.
[QUOTE=But this x-over looks to be less complex than the swifty x-over.[/QUOTE]


A bit but a few resisters are cheap, and the LP circuit is simpler so a bit of a wash.
  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
74HC logic or No logic feedingthe Interface Receiver. Mario_JR Digital Source 2 10th July 2011 09:18 PM
XO for Vifa PL18WO-08-09 and Vifa XT25TG30-04 MTM knightat83 Multi-Way 6 24th January 2009 09:51 AM
PA speaker X-0VER oquela PA Systems 9 29th August 2007 02:37 AM
74AC logic V.S. 74HC logic ? fastcat95 Digital Source 0 16th December 2006 04:03 PM
What happened to Logic by Vifa? sardonx Multi-Way 1 19th January 2006 12:32 PM


New To Site? Need Help?

All times are GMT. The time now is 11:52 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2015 DragonByte Technologies Ltd.
Copyright 1999-2015 diyAudio

Content Relevant URLs by vBSEO 3.3.2