Crossover advice - 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 19th November 2008, 05:38 PM   #1
zega55 is offline zega55  Croatia
diyAudio Member
 
zega55's Avatar
 
Join Date: Apr 2006
Location: Zagreb
Default Crossover advice

Hi , guys

I am building a 2-way loudspeaker.
I have two Peerles 831882
and two Seas 27TFFC

The box will be 8.6L BR.
Tuned to 57hz.

Can you give me a advice about the crossover network?
Could I use a crossover design from here
I found this project , and it uses almost the same driver.
The woofer is the same one , but the tweeter is the one without ferroflouid and it has a soft polymer surround , while mine has
sonolex surround.
__________________
Ivan
  Reply With Quote
Old 19th November 2008, 08:45 PM   #2
diyAudio Member
 
sdclc126's Avatar
 
Join Date: Jan 2005
Location: San Diego, CA
Good choice of drivers.

Someone may design a crossover for you here, but why not learn how to do it yourself?

http://www.rjbaudio.com/Audiofiles/FRDtools.html

Also this site will be useful - read the driver test pages:

www.zaphaudio.com
__________________
Soft Dome
  Reply With Quote
Old 20th November 2008, 01:44 AM   #3
zega55 is offline zega55  Croatia
diyAudio Member
 
zega55's Avatar
 
Join Date: Apr 2006
Location: Zagreb
Thanks for the advice.
Zaph pages ware the guideline in chousing the woofer , and the looks of the woofer had to do somethig with it.
It has low distortion , and a nice response.

I wanted only an advice where to cross , and what type of a crossover should I use.

Well , I know that 6db per octave wouldn"t work.
And I know about the woofers response it has a bump after 2kHz.
__________________
Ivan
  Reply With Quote
Old 20th November 2008, 03:33 AM   #4
infinia is offline infinia  United States
diyAudio Member
 
infinia's Avatar
 
Join Date: May 2005
Location: Californication
Quote:
Originally posted by zega55

And I know about the woofers response it has a bump after 2kHz.
That's the result of picking a driver with a pole piece, i.e. extended response inc. the cone breakup. Makes the crossover more difficult/complicated now. IMO concave cone shapes allows use of combined acoustical rolloff with the electrical response much simpler.


compare to http://www.tymphany.com/files/products/pdf/832873.pdf

lower Fs as well
I guess it's not as sexy looking tho.
__________________
like four million tons of hydrogen exploding on the sun
like the whisper of the termites building castles in the dust
  Reply With Quote
Old 20th November 2008, 10:34 AM   #5
HK26147 is offline HK26147  United States
diyAudio Member
 
Join Date: Jan 2008
zega55
I would suggest 2Khz.
I would also use a more aggressive slope than 12db/octave.
Since this is an untested design(?), I would be tempted to outboard the xover to allow for experimentation and evaluation.
One of the advantages of active crossovers is more aggressive filter rate 24 - 48db/octave which allows for a lower xover point and easy of experimentation.
  Reply With Quote
Old 20th November 2008, 11:11 AM   #6
infinia is offline infinia  United States
diyAudio Member
 
infinia's Avatar
 
Join Date: May 2005
Location: Californication
As suggested LPF at 2KHz seems to make sense.
Could use non-textbook 2nd order (low Q) and space the HPF further up to sum better on axis.
__________________
like four million tons of hydrogen exploding on the sun
like the whisper of the termites building castles in the dust
  Reply With Quote
Old 20th November 2008, 01:48 PM   #7
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Default Re: Crossover advice

Quote:
Originally posted by zega55

Could I use a crossover design from here
I found this project , and it uses almost the same driver.
The woofer is the same one , but the tweeter is the one without ferroflouid and it has a soft polymer surround , while mine has
sonolex surround.
Hi,

That design appears to have no BSC and thus is not recommended.

I'd suggest you learn what you are doing to choose the c/o point,
the acoustic slopes of the crossover and the electrical components
required to reach your targets.

e.g. :


Quote:
The crossover is an acoustic 4th order at 1950 Hz, and is nearly a symmetrical Linkwitz-Riley thanks to the woofer's shallow acoustic center. To reach the target slopes, 2nd order electrical plus an L-pad was used on the tweeter, and 3rd order electrical was used on the woofer. The tweeter has an impedance peak to deal with, but I was able to get enough damping out of the shunt resistor to not need an impedance flattening LRC circuit. The woofer has a breakup node but it was high enough to not require extra components in the crossover.
/sreten.
  Reply With Quote
Old 21st November 2008, 12:48 AM   #8
zega55 is offline zega55  Croatia
diyAudio Member
 
zega55's Avatar
 
Join Date: Apr 2006
Location: Zagreb
By BSC you mean baffle step compensation?
__________________
Ivan
  Reply With Quote
Old 21st November 2008, 12:57 AM   #9
diyAudio Member
 
sdclc126's Avatar
 
Join Date: Jan 2005
Location: San Diego, CA
He does.
__________________
Soft Dome
  Reply With Quote
Old 21st November 2008, 09:59 PM   #10
Jay_WJ is offline Jay_WJ  United States
diyAudio Member
 
Join Date: Mar 2006
Location: Indiana
Quote:
Originally posted by zega55
Can you give me a advice about the crossover network?
Could I use a crossover design from here
I found this project , and it uses almost the same driver.
The woofer is the same one , but the tweeter is the one without ferroflouid and it has a soft polymer surround , while mine has
sonolex surround.
Right, the crossover you linked in your post has nearly zero baffle step compensation.

I can model a crossover for you. What's your baffle size? What's your speaker placement?

-jAy
  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
crossover advice please REALFLEO Multi-Way 6 18th December 2006 11:53 AM
crossover advice please welly_59 Multi-Way 6 30th November 2003 07:33 PM
need crossover advice-help finetune Multi-Way 4 22nd October 2003 01:35 PM
Need advice on crossover zverina Multi-Way 2 22nd March 2003 07:36 AM
Modifying Crossover Advice BigMacX Multi-Way 2 6th August 2002 08:49 AM


New To Site? Need Help?

All times are GMT. The time now is 06:51 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