Impedance Bass Reflex - check up Beyma 12B100R - Page 2 - 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 16th October 2012, 09:44 PM   #11
Dissi is offline Dissi  Switzerland
diyAudio Member
 
Join Date: Sep 2012
Location: Winterthur
Quote:
Originally Posted by jzagaja View Post
Notch is centered at 300Hz.
... and has an impedance of approximately 80 ohm at 50 Hz. Is the capacitor 47 uF?

Last edited by Dissi; 16th October 2012 at 09:52 PM.
  Reply With Quote
Old 16th October 2012, 10:33 PM   #12
VaNarn is offline VaNarn  Australia
diyAudio Member
 
Join Date: Dec 2010
Location: Ivanhoe
jzagaja,going back to your original questions;I would comment that if you compromise the enclosure size to a 60L internal volume,then you will need to use a higher Fb ''tuning'' to compensate for a non-classic alignment.The other anomaly that is shown in your last graph is an incorrectly calculated impedance correction network.
  Reply With Quote
Old 17th October 2012, 05:42 AM   #13
jzagaja is offline jzagaja  Poland
diyAudio Member
 
Join Date: Jun 2004
Location: Szczecin
Send a message via Skype™ to jzagaja
Quote:
Originally Posted by VaNarn View Post
The other anomaly that is shown in your last graph is an incorrectly calculated impedance correction network.
Can you show me where? I have two ports 6.5cm dia, 11cm long so when two are opened then tuning is high (>40Hz) while with one closed is low (<35Hz). With two opened kick-bass is missing for sure.
__________________
Visit us at http://www.horns.pl/
The SEOS™ Project http://www.avsforum.com/t/1291022/he...-rallying-here
  Reply With Quote
Old 17th October 2012, 09:11 AM   #14
VaNarn is offline VaNarn  Australia
diyAudio Member
 
Join Date: Dec 2010
Location: Ivanhoe
I would need far more details of what you are wanting from your application to try to attempt a full reply.Your last entry adds information on two vents which is not mentioned previously.If I had a bass speaker that measured after full ageing,the T&S parameters given;I would look at a classic fourth order Butterworth alignment with expected losses,giving alpha =1.06.This results in an enclosure with an effective volume of 145.3L ,with an Fb of 28Hz.the resulting Fl should equal 14.24 Hz and Fh should be 55 Hz.If you are trying to use an electronic transform to achieve better results in order to use a small enclosure, or other corrections to satisfy your design target;you will need to give more details of your approach so far..
  Reply With Quote
Old 17th October 2012, 09:16 AM   #15
jzagaja is offline jzagaja  Poland
diyAudio Member
 
Join Date: Jun 2004
Location: Szczecin
Send a message via Skype™ to jzagaja
Shouldn't Beyma 12B100R be used below 80 liters? My enclosure is 60-65 liters and I'm validating simulations. Beyma 12BR70 for example has more kickbass.
__________________
Visit us at http://www.horns.pl/
The SEOS™ Project http://www.avsforum.com/t/1291022/he...-rallying-here
  Reply With Quote
Old 17th October 2012, 10:06 AM   #16
VaNarn is offline VaNarn  Australia
diyAudio Member
 
Join Date: Dec 2010
Location: Ivanhoe
Under sized enclosures are the compromise that the marketing people push in an effort to promote sales.If you are restricted by cabinet volume,then you will have to accept a higher tuning freq. for the bass reflex with the result of coloured sound irrespective of computer simulations to the contrary.The Beyma engineers have on the indications manufactured an excellent product and if you abide by what the T&S parameters tell you ,a first class bass performance is achievable.Furthermore,although the available literature on the 12B100R does not discuss larger enclosures(which is what you have based your construction on) any competent designer should be able to proceed to better implementations.
  Reply With Quote
Old 17th October 2012, 10:12 AM   #17
jzagaja is offline jzagaja  Poland
diyAudio Member
 
Join Date: Jun 2004
Location: Szczecin
Send a message via Skype™ to jzagaja
I’m afraid in larger box (close to Vas) bass will be even more anemic. But maybe I should try it anyway.
__________________
Visit us at http://www.horns.pl/
The SEOS™ Project http://www.avsforum.com/t/1291022/he...-rallying-here
  Reply With Quote
Old 17th October 2012, 01:09 PM   #18
Dissi is offline Dissi  Switzerland
diyAudio Member
 
Join Date: Sep 2012
Location: Winterthur
I checked my simulation. 62.5 litres and two ports of 65 x 110 mm give a tuning frequency of 43 Hz and a -3 dB frequency around 50 Hz. I would need to know your current crossover to tell more. If crossed low, the filter usually influences the low end and yields unexpected results! VaNarn is certainly right, you can get more kickbass using a volume of 100 litres or more.
  Reply With Quote
Old 17th October 2012, 03:01 PM   #19
diyAudio Member
 
Join Date: Sep 2007
I would love to see the results of this. The 12B100R is a great driver and can give great bass output if used correctly. This driver is not used enough and generally is much over looked. Give it a good bash
  Reply With Quote
Old 17th October 2012, 03:27 PM   #20
diyAudio Member
 
KaffiMann's Avatar
 
Join Date: Sep 2009
Quote:
Originally Posted by Stuart Angus View Post
I would love to see the results of this. The 12B100R is a great driver and can give great bass output if used correctly. This driver is not used enough and generally is much over looked. Give it a good bash
I have also been very curious about this driver.

Low fs, but what about the xmax? Is it usable to 30hz at loud volumes?
  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
Bass Reflex Enclosure for Beyma 10BR60 -_nando-_ Multi-Way 7 22nd June 2013 01:25 PM
:) Check my first Bass Reflex 6 ports, 2 driver standard configuration design :) endrek Subwoofers 31 11th April 2011 05:37 PM
Bass reflex box for Beyma 8ag/n bubuxxl Full Range 29 21st October 2010 12:20 PM
Best bass out of Beyma 18 p1000 ??? slacker0001 Multi-Way 1 13th July 2005 03:38 PM
bass reflex? GAK Multi-Way 2 23rd October 2001 03:04 AM


New To Site? Need Help?

All times are GMT. The time now is 10:38 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