? Active crossover with constant phase ? - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 2nd July 2001, 04:04 PM   #1
diyAudio Member
 
promitheus's Avatar
 
Join Date: Jan 2001
Location: Germany
HI everybody !!
I need some help. There is this design of active crossovers using time shift filters. This crossover has no difference in phase between high and low frequencies. There used to be an article in the Elektor magazine. But I can´t find any info anymore. If anyone knows a link or something please post.
Thanks, Ilias.
  Reply With Quote
Old 2nd July 2001, 05:22 PM   #2
jam is offline jam  United States
diyAudio Member
 
jam's Avatar
 
Join Date: May 2001
Location: Auburn, CA, USA
Default Phase Linear Cross-Over

Ilias,

Elector published a book High-end Audio Equipment in 1995 and the article you want ( Active phase-linear cross-over net network) is in that book.

If you have any problems finding it please e-mail me.

Jam

P.S. Nelson Pass also published an article on subtractive (linear phase) cross-overs and I believe this is available on the Pass Labs web site.

[Edited by jam on 07-02-2001 at 12:25 PM]
  Reply With Quote
Old 3rd July 2001, 08:54 AM   #3
Alex M is offline Alex M  United Kingdom
diyAudio Member
 
Join Date: Apr 2001
Location: Hampshire, UK
A further possibility for linear phase filters is that of
filler (Baekgard) drivers.

You can do a Web search for Baekgard for more information. I
have written a short note on this at

http://www.soton.ac.uk/~apm3/diyaudi...r_drivers.html

Alex
  Reply With Quote
Old 3rd July 2001, 01:13 PM   #4
diyAudio Member
 
promitheus's Avatar
 
Join Date: Jan 2001
Location: Germany
Thanks a lot for all the help.
If anybody has a link or file of the elektor active crossover I would really be interested in having a copy.
Thanks again
  Reply With Quote
Old 3rd July 2001, 02:07 PM   #5
ALW is offline ALW  United Kingdom
diyAudio Member
 
Join Date: Jun 2001
Location: UK
Default Phase coherent crossover

There's 2/3 way 24dB/oct Linkwitz-Riley design at http://sound.au.com/project09.htm.

Spice model I did looks good, phase coherent at the crossover point.

Andy.
  Reply With Quote
Old 3rd July 2001, 02:22 PM   #6
Alex M is offline Alex M  United Kingdom
diyAudio Member
 
Join Date: Apr 2001
Location: Hampshire, UK
Ah, but there's a difference between a crossover which is
"linear phase" and one that's "phase coherent at the
crossover point". The first reproduces (at least in theory)
a transient perfectly, while the second simply ensures that
the two drivers are moving in the same direction at the
same time at the crossover frequency. Linkwitz Riley
crossovers are in the second category; here (I think!) we
are talking about the first kind, which is much harder to
put into practice.

Alex


[Edited by Alex M on 07-03-2001 at 09:24 AM]
  Reply With Quote
Old 3rd July 2001, 07:28 PM   #7
diyAudio Member
 
promitheus's Avatar
 
Join Date: Jan 2001
Location: Germany
The circuit I am talking about that ws published in the Elektor magazine is an active crossover that has the smae phase in all the drivers for every frequency not only at the cross over point.
  Reply With Quote
Old 4th July 2001, 08:19 AM   #8
ALW is offline ALW  United Kingdom
diyAudio Member
 
Join Date: Jun 2001
Location: UK
Default Phase coherent

The design above is almost perfectly phase coherent across most of the audio band (there's some minor deviation at very low frequqncies). The only reason for specifically mentioning crossover point was this is often the worst area.

Worth a peek.

Andy.
  Reply With Quote
Old 4th July 2001, 09:36 AM   #9
diyAudio Member
 
promitheus's Avatar
 
Join Date: Jan 2001
Location: Germany
Yeah it looks good. It´s a little different than the one I read before but I will test it out too on simulation.
Thanks again.
  Reply With Quote
Old 4th July 2001, 11:45 AM   #10
ALW is offline ALW  United Kingdom
diyAudio Member
 
Join Date: Jun 2001
Location: UK
Default Helpful software

Promitheus,

Since you're obviously into SPICE, you may find the following application useful. It's 'Filter Wiz' available in LE or Pro versions (http://www.schematica.com/).

There are partly working demo's available, its' a very easy to use wizard-style application, that allows the design of active filters in Butterworth, Chebyshev, Inverse Chebyshev, Elliptic or Bessel / Thompson alignments.

One can force filter orders, or define by pass / stopband performance. It's great for creating crossovers, since one can easily prototype a design, fine tune in SPICE modelling and just build the final design.

Saves a lot of time with a soldering iron!

Andy.
  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
Modified Fender Deluxe - Constant Current Phase Splitter lcsegeng Tubes / Valves 6 26th February 2007 07:22 PM
Constant Amplitude Phase Shift - CAPS Circuit mskeete Solid State 1 5th June 2005 03:38 AM
Active crossover with linear phase response ackcheng Solid State 1 20th July 2004 05:54 AM
Phase splitters: Constant current sources BlackUnikorn Tubes / Valves 10 25th November 2003 02:44 AM
active plate load v.s. constant current... mwmitchell Tubes / Valves 3 8th August 2002 09:34 PM


New To Site? Need Help?

All times are GMT. The time now is 01:53 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