Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Multi-Way Conventional loudspeakers with crossovers

Crossover design problems/suggestions
Crossover design problems/suggestions
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 13th March 2018, 08:31 PM   #11
XMechanik is offline XMechanik  Poland
diyAudio Member
 
Join Date: Dec 2017
Quote:
Originally Posted by sese317j View Post
In the text from Jeff Bagby's it is mentioned to connect the drivers in parallel while remaining the polarity, but the problem ist my amp is not 2ohm stable, so is it possible to connect a 4ohm Resistor in series to the two drivers connected in parallel to keep the overall impedance of two 4 Ohm drivers above 2 Ohm ?
Wouldn't it be a solution if you connect the tweeter to the right output, mid-woofer to the left output, and put the same signal on both inputs? A "mono" button would be useful, if you have one in your amp.
__________________
XMachina page thread
  Reply With Quote
Old 13th March 2018, 09:08 PM   #12
sese317j is offline sese317j  Germany
diyAudio Member
 
Join Date: Apr 2017
I already did the measurement, but i totaly screwed up. I did the measurement of the tweeter on axis with the tweeter, the measurement of the woofer on axis with the woofer, and placed the mic between the drivers, to measure both of the drivers connected in parallel. I overread that all of the measurements need to be taken without moving the mic, so my measurements are not usable for calculating the offset. The amp did just fine with both of the drivers connected in parallel, but the idea to use both channels is also worth a try. Thanks for your help, i will post new and hopefully correct measurements tomorrow.
  Reply With Quote
Old 14th March 2018, 04:25 PM   #13
sese317j is offline sese317j  Germany
diyAudio Member
 
Join Date: Apr 2017
Default driver offset

Measured again today, imported them into the passive crossover calculator.

Click the image to open in full size.

The woofer is 14 cm below the tweeter and the measurements were taken from 50 cm away. The final offset of the tweeter is 3.8 cm or 1.5 inch.
  Reply With Quote
Old 14th March 2018, 07:29 PM   #14
EarlK is offline EarlK  Canada
diyAudio Member
 
Join Date: Mar 2006
Location: Toronto (GTA), Ontario
My Advice?

To confirm that 1.5 inch ( offset ) figure;

- Create a new network prediction in your design software utilizing only LCR parts that you currently have on hand ( the test network can really be anything that doesn't smoke your amplifier ).
- Wire up your "test network" to your drivers.
- Measure the resulting curve of one speaker.
- Compare "software prediction" to "reality" .

- If you make these measurements from the same exact location that you used to make the new files ( used to figure out the "offset" ), then the curves should to be the same.


Last edited by EarlK; 14th March 2018 at 07:57 PM.
  Reply With Quote
Old 14th March 2018, 08:49 PM   #15
EarlK is offline EarlK  Canada
diyAudio Member
 
Join Date: Mar 2006
Location: Toronto (GTA), Ontario
Hi,

Here's my final effort for you ( using your 1.5" offset figure ).

HF has been increased ( above 10K > though usually that's not that critical for a PA speaker ).

Crossover design problems/suggestions-6in-pa-speaker_trace_modl-png

- The red trace uses "Auditory ERB" smoothing which offers a good representation of human hearing ( resolution wise ).

- I've zipped and included the XSim file for you to play with.
( the woofer section has 2 notch filters > see if you can find a way to eliminate one or both of them ).

Attached Images
File Type: png 6in PA Speaker_Trace_modL.png (15.9 KB, 150 views)
Attached Files
File Type: zip 6inch PA Speaker_modL.zip (945.4 KB, 3 views)

Last edited by EarlK; 14th March 2018 at 09:04 PM.
  Reply With Quote
Old 14th March 2018, 09:44 PM   #16
sese317j is offline sese317j  Germany
diyAudio Member
 
Join Date: Apr 2017
So i tried some things in Xsim, and thats what i came up with :

Click the image to open in full size.

Click the image to open in full size.


Quote:
Originally Posted by EarlK View Post
Hi,

Here's my final effort for you ( using your 1.5" offset figure ).
I overlayed them both, and then the superiority of your crossover design gets really obvious. (the red one is my design)

Click the image to open in full size.

Why should i try to eliminate the notch filters, do they have any bad impact on the sound ?

Thank you so much for your effort in helping me, i m just amazed how great and helpful this community is. Thank you.
  Reply With Quote
Old 15th March 2018, 09:24 PM   #17
EarlK is offline EarlK  Canada
diyAudio Member
 
Join Date: Mar 2006
Location: Toronto (GTA), Ontario
You're very welcome !

Since you had frd & zma files, I was glad to help out.

Notch Filters ?
There's nothing much controversial about the selective use of notch filters ( apart from the fact they use more components ).

Crossover design problems/suggestions-6in-pa-speaker_schematic-modm_-png

The two here ( in the woofer section ) are located out in the stop-band helping to steepen the slope of the low-pass filter.

Attached Images
File Type: png 6in PA Speaker_Schematic modM_.png (10.8 KB, 128 views)
  Reply With Quote
Old 15th March 2018, 09:55 PM   #18
sese317j is offline sese317j  Germany
diyAudio Member
 
Join Date: Apr 2017
Tomorrow i m going to do some more measurements to confirm that my offset is correct, and then im ready to build the final enclosure. I m so excited to listen to the speaker for the first time.
  Reply With Quote
Old 16th March 2018, 11:44 PM   #19
XMechanik is offline XMechanik  Poland
diyAudio Member
 
Join Date: Dec 2017
Yet another "90dB" approach. What I see as an advantage is that the circuit has only 3 coils, so there should be no problems with separations, directions etc. The elements are easy to acquire: the coils are from JantzenAudio list, the rest of the elements have standard values.
Attached Images
File Type: jpg mo_em_1.5i_4r_3L_5C.jpg (342.3 KB, 88 views)
Attached Files
File Type: zip mo-em-1.5inch_ph_meas.zip (945.1 KB, 1 views)
__________________
XMachina page thread
  Reply With Quote
Old 17th March 2018, 08:37 PM   #20
sese317j is offline sese317j  Germany
diyAudio Member
 
Join Date: Apr 2017
Default Maybe another tweeter

I tried to confirm my offset, and i tried 3 times and got three different results all the way from 1.4" to 2.1". I m thinking of replacing the Eminence atp80 with another tweeter that has a "simpler" response curve and not so many dips. As Peerless by Tymphany drivers are now finaly avaliable from sound imports, it is much easier and cheaper to buy them in germany, and i think the DA25BG08-06 would be the best choice. Additionaly i could use a much lower crossover point, which would simplify the crossover section of the woofer.
  Reply With Quote

Reply


Crossover design problems/suggestionsHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
XO3: The 1/2/3-way Active Crossover/filter PCB. Design suggestions welcome! s3tup Analog Line Level 52 5th October 2011 03:27 PM
<AUS> B3S active crossover design - Value woofer suggestions? TheSeekerr Multi-Way 0 25th August 2008 12:46 PM
Suggestions on OB problems maoumaou Multi-Way 13 29th February 2008 02:35 AM
Suggestions on my crossover design? JoeyDD Multi-Way 11 11th December 2005 02:05 PM
Amp problems, suggestions needed :( fedx Solid State 3 21st October 2005 03:38 AM


New To Site? Need Help?

All times are GMT. The time now is 02:56 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki