Go Back   Home > Forums > >

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
Old 30th July 2021, 03:45 PM   #7501
gedlee is offline gedlee  United States
diyAudio Member
 
gedlee's Avatar
 
Join Date: Dec 2004
Location: Novi, Michigan
Quote:
Originally Posted by mabat View Post
That's just tied to the amplitude response, i.e. there's simply a resonance somewhere inside the driver.
That's the diaphragm resonance - surprisingly low damping for a compression driver.
__________________
Earl Geddes Gedlee Website
  Reply With Quote
Old 30th July 2021, 03:54 PM   #7502
mabat is offline mabat  Czech Republic
diyAudio Member
 
mabat's Avatar
 
Join Date: Sep 2004
Location: Prague, Czechia
Oh, I see. BTW, this is the throat impedance of the WG used. So is there a chance that in a waveguide that has a higher throat impedance to a lower frequency, the dip between 1 - 2 kHz won't be as pronounced?

-swg33-throat-impedance-png
Attached Images
File Type: png SWG33-throat-impedance.PNG (15.4 KB, 1337 views)
__________________
https://at-horns.eu
  Reply With Quote
Old 30th July 2021, 04:18 PM   #7503
ErnieM is offline ErnieM  United States
diyAudio Member
 
Join Date: Dec 2009
Location: Fresno, CA
Here's another measurement of the HF1440 I forgot about.

HF1440 New Ring Compression Driver from Faital Pro.
  Reply With Quote
Old 30th July 2021, 04:22 PM   #7504
mabat is offline mabat  Czech Republic
diyAudio Member
 
mabat's Avatar
 
Join Date: Sep 2004
Location: Prague, Czechia
Thanks. So we want a horn with throat impedance peaking just above the fundamental driver resonance, don't we. Damn, this calls for a lumped-element model of the driver.
__________________
https://at-horns.eu

Last edited by mabat; 30th July 2021 at 04:26 PM.
  Reply With Quote
Old 30th July 2021, 07:33 PM   #7505
gedlee is offline gedlee  United States
diyAudio Member
 
gedlee's Avatar
 
Join Date: Dec 2004
Location: Novi, Michigan
AS you might expect, the coupling of the elements around resonance can get complex and unintuitive. Models are usually required.

But at these L(ish)Fs the waveguides impedance looks like a simple mass. The dual humps in the electrical impedance curve are due to the coupled oscillator defined by the gap compliance and the two masses - waveguide and diaphragm. At the lower impedance you have the two masses in phase and the above peak they are out of phase, i.e. 180 degree phase shift. This coupling makes the whole problem much more complex.
__________________
Earl Geddes Gedlee Website
  Reply With Quote
Old 30th July 2021, 10:03 PM   #7506
Zvu is offline Zvu  Serbia
diyAudio Member
 
Zvu's Avatar
 
Join Date: Jan 2009
Location: Belgrade
This evening my friend Jokerbre and i measured Peerless DFM2535R00-08 on Mabat's ST260 waveguide.

Measurements are done from 1m distance with calibrated Behringer ECM8000, Steinberg UR12 and gate frequency of 4.4ms so enough to capture trends of this waveguide. What is shown here are measurents 0-90 degrees with ≈7.5 deg increments in between. Since i did not calibrate REW and my mic for loudness, SPL levels shown aren't representative of actual SPL level. Off axis measurements 60 degrees and up are smoothed 1/48 to avoid "hair" at higher frequencies.

0-90 degrees
0-90 степени.jpg

0-45 degress
0-45 степени.jpg

45-90 degrees
45-90 степени.jpg

75dB vs 85dB loudness
75 85.jpg

measurement on axis (red) and averaged 0-90 degrees (purple)
мерење на оси и п&.jpg

printed waveguide
звуковод напре .jpg звуковод назад.jpg

I must say that i've never seen better and more extended frequency response from a smaller waveguide and a cheaper compression driver.
__________________
Tesla; George Carlin

Last edited by Zvu; 30th July 2021 at 10:33 PM.
  Reply With Quote
Old 30th July 2021, 10:07 PM   #7507
tmuikku is offline tmuikku  Finland
diyAudio Member
 
Join Date: Sep 2004
Location: Savo, Finland
Send a message via ICQ to tmuikku
Nice!
  Reply With Quote
Old 30th July 2021, 10:22 PM   #7508
Kevmoso is offline Kevmoso  United States
diyAudio Member
 
Join Date: Nov 2012
Location: Sacramento CA
Very nice indeed. Nice looking print quality as well.
Same quality of directivity results I measured with a different driver, BMS 4552nd. ST260 is a killer little waveguide.
Such good directivity I am left wondering what would be a good match below.
Side by side 8s and a 15 below is one thought.
  Reply With Quote
Old 30th July 2021, 10:30 PM   #7509
Zvu is offline Zvu  Serbia
diyAudio Member
 
Zvu's Avatar
 
Join Date: Jan 2009
Location: Belgrade
I have a pair of FaitalPro 12pr320-8 i must spend somehow.

Quote:
Originally Posted by Kevmoso View Post
Very nice indeed. Nice looking print quality as well.
0.2mm nozzle with 20% infill.
__________________
Tesla; George Carlin

Last edited by Zvu; 30th July 2021 at 10:47 PM.
  Reply With Quote
Old 30th July 2021, 11:12 PM   #7510
Kevmoso is offline Kevmoso  United States
diyAudio Member
 
Join Date: Nov 2012
Location: Sacramento CA
A 12" is "the other" option I have considered but I always like to complicate things for myself... That 12pr320 you have is a nice nice NICE option!
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools

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
Easy horn (Eazy Horn) still work? Alternatives? Soldermizer Subwoofers 2 4th March 2014 05:01 PM
For sale: Sound easy V18 & Acoustic-dimension stepped attenuator Tazzz Swap Meet 8 3rd November 2012 08:00 AM
easy exponential horn speakers anyone? 12345chris Full Range 9 21st March 2012 11:32 AM
Easy horn, quadrant horn? Hentai Multi-Way 2 29th January 2012 08:50 AM
An easy to build classic horn? dabbler Multi-Way 22 1st September 2011 08:01 AM


New To Site? Need Help?

All times are GMT. The time now is 02:52 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2021 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2021 DragonByte Technologies Ltd.
Copyright ©1999-2021 diyAudio
Wiki