Question on LspCAD and Behringer DCX2496 - diyAudio
Go Back   Home > Forums > Source & Line > Digital Line Level

Digital Line Level DACs, Digital Crossovers, Equalizers, etc.

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 24th September 2007, 01:12 PM   #1
JonW is offline JonW  United States
diyAudio Member
 
Join Date: Jul 2006
Default Question on LspCAD and Behringer DCX2496

I just modeled a passive crossover in LspCAD. I think I have it to the point where it looks good. I also have a Behringer DCX2496 that Iíve not yet had a chance to use. I thought there was a way I could connect my PC and DCX2496 in order to have the DCX2496 run the modeled crossover. But Iím not seeing how thatís done. After reading the manuals, looking through the software, etc. Iím now thinking that LspCAD cannot dump a passive crossover model into the DCX2496. It will only work with a modeled active crossover. Is that all correct? Or is there a way I can try out my passive crossover model in the DCX2496? Thanks!

-Jon
  Reply With Quote
Old 24th September 2007, 02:31 PM   #2
diyAudio Member
 
Join Date: May 2004
Location: Hertfordshire
Jon,
You need to have a knowledge of the DCX2496 crossover possibilities before you tweak your LSPCAD models. There is quite a range of crossovers but you need to be aware of what is avaliable and then force the LSPCAD model to adopt what is possible on the DCX2496.
I would have a play with the 2496 and then go back to your model.
  Reply With Quote
Old 24th September 2007, 05:29 PM   #3
JonW is offline JonW  United States
diyAudio Member
 
Join Date: Jul 2006
Thanks. That's the impression I was getting. I see how the DCX2496 can do various crossover points, slopes, etc. But that's all pretty simple stuff. What about mimicing a more complicated passive circuit? SomehowI thought that you could send that all into the DCX2496. But, like you say, after playing around with it some, it doesn't look to be the case. Oh well. I think I'll try and simulate my crossover by getting a bunch of caps, inductors, and resistors. Clip them together and see how that sounds.
  Reply With Quote
Old 24th September 2007, 06:06 PM   #4
EspenE is offline EspenE  Norway
diyAudio Member
 
Join Date: Jun 2003
Location: Oslo
Correct.
You cannot directly "dump" a passive crossover network model into the DCX 2496.

But what you can do (in lspCAD 6) is modelling the network directly on basis of the DCX crossover possibilities. In my experience, the DCX has enough possibilities to facilitate almost any transfer function.

OR you could export the transfer functions from your passive network model to .frd-files and then use those as target curves for the DCX optimization. Still requires version 6, though.

Both methods are definitely different processes than modelling with coils and caps. Generally: when modelling with DCX you have less flexibility on filter slopes and filter q values - but more flexibility on notch/peak filters, level settings and phase correction.

Espen
  Reply With Quote
Old 24th September 2007, 08:45 PM   #5
JonW is offline JonW  United States
diyAudio Member
 
Join Date: Jul 2006
Thanks Espen. Yes, I'm using LspCAD version 6.

When my speakers are complete, I want to run them passive, not with the DCX2496. I could now put the simple aspects of my crossover into the DCX2496- things like what the crossover point is, what the slopes are, etc. (I'll definitely try that.) But I will not get all the smaller details I spent time modeling into my passive crossover.

So if what I am after is a passive crossover, how much effort would you say to put into testing with the DCX2496 before switching over to trying out variations with real caps, inductors, and resistors?

-Jon
  Reply With Quote
Old 25th September 2007, 07:55 AM   #6
EspenE is offline EspenE  Norway
diyAudio Member
 
Join Date: Jun 2003
Location: Oslo
Hi Jon -

if a passive filter is what you're after, I personally would not put much effort into modelling a DCX-based crossover with lspCAD, but rather start modelling with passive components directly.

In my view the two approaches are so different that modelling/experimenting with the basic crossover concepts (ie: frequencies, slopes) in the DCX doesn't help you much when designing/modelling a passive network.


Espen
  Reply With Quote
Old 25th September 2007, 08:23 AM   #7
diyAudio Member
 
Join Date: May 2004
Location: Hertfordshire
I am using the 2496 to develop some active cross-overs so I am restraining myself to use the standard crossovers offered. This makes it easy to implement the hardware. I suppose you could do the same with passive crossovers but this would not allow optimisation.
Behringer should make the crossover filters with adjustable Q though, so that you could have underdamped or overdamped filters and hence could cope with the optimisation LSPCAD allows.
  Reply With Quote
Old 26th September 2007, 03:42 PM   #8
JonW is offline JonW  United States
diyAudio Member
 
Join Date: Jul 2006
Thanks guys. I have the DCX2496 around, so I played with it a little last night. Got my drivers (Scanspeak 6600 tweeter and 18W/8531 woofer) in ugly, sharped edged boxes just for measurements and testing. I did a very rough estimation of my passive crossover (2500 Hz, 3rd order both sides) and it didn't sound great. But when I moved the crossover point up or down a lot, it sounded worse. 4th order slopes sounded a little better, maybe. Then I tried some quick things like what I did with the passive crossover- dropped the tweeter level and boosted the bass around 150 Hz. That made it sound a little better. But it never sounded too good.

Interesting, but it's now probably time to play with real caps, inductors, and resistors.
  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 Behringer DCX2496 tommycomm Digital Line Level 1 4th June 2008 07:33 PM
Behringer DCX2496 12 Cents Swap Meet 0 29th July 2007 08:27 AM
Behringer DCX2496 Spearmint Digital Line Level 117 31st January 2007 04:57 PM
Behringer DCX2496 RAAMaudio Swap Meet 0 19th February 2006 07:15 PM
Behringer DCX2496 12v ps Flyingeyepro Car Audio 0 30th July 2004 08:05 PM


New To Site? Need Help?

All times are GMT. The time now is 09:09 AM.


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