Zobel Network for Fostex FE83En - diyAudio
Go Back   Home > Forums > Loudspeakers > Full Range

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 5th May 2012, 11:33 PM   #1
dbek is offline dbek  United States
diyAudio Member
 
Join Date: Feb 2012
Default Zobel Network for Fostex FE83En

Hi everyone, I've been reading this site for a little while now, but this will be my first post. I'm pretty new to speaker building, but I'm really enjoying it!

I've built some small bookshelf speakers with the 3" Fostex FE83En drivers. I want to put in a zobel network on the speakers. I was planning on using a 7.5 Ohm 10W Resistor and a 0.33uF 250V Polypropylene Capacitor. Does that right? or did I totally mess up the calculations?

Thanks, for your help.
  Reply With Quote
Old 6th May 2012, 12:42 AM   #2
diyAudio Member
 
DBMandrake's Avatar
 
Join Date: Nov 2010
Location: Glasgow, UK
Are you driving the speaker through some sort of passive filter/crossover or just directly connected to the amplifier ? If it's just direct then a zobel network will make no difference to the response as it's purpose is to flatten the impedance curve seen by a passive crossover/network.

(Edit: to be thorough, this is only true if the amplifier has a low output impedance, as in the case of nearly all solid state amplifiers, if you're using a valve amp with an output impedance as high as several ohms, there will be a difference)

In any case I find calculations for zobel networks based on the DC resistance and nominal inductance figures of the driver are only approximate, as the inductance is not a "pure" inductance due to the solenoid and motional effects of the driver. It's always best to fine tune the values by actually measuring the resulting impedance curve of the driver and zobel together.
__________________
- Simon

Last edited by DBMandrake; 6th May 2012 at 12:49 AM.
  Reply With Quote
Old 6th May 2012, 01:18 AM   #3
dbek is offline dbek  United States
diyAudio Member
 
Join Date: Feb 2012
Thanks for replying to my post. The speaker is directly connected to a small class-t amplifier. There are no crossovers, since there is only one driver in the speaker box. I guess then, there's no need for the zobel network?
  Reply With Quote
Old 6th May 2012, 02:44 AM   #4
frugal-phile(tm)
diyAudio Moderator
 
planet10's Avatar
 
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Blog Entries: 5
Quote:
Originally Posted by dbek View Post
The speaker is directly connected to a small class-t amplifier.
Class T amps tend to like flat impedance too.

dave
__________________
community sites t-linespeakers.org, frugal-horn.com, frugal-phile.com ........ commercial site planet10-HiFi
p10-hifi forum here at diyA
  Reply With Quote
Old 6th May 2012, 05:54 PM   #5
diyAudio Member
 
tuxedocivic's Avatar
 
Join Date: Jan 2011
Location: Ladysmith, BC
0.33uF can't be right. Maybe 33uF?

I'll be working with this driver soon. I could let you know in a couple months.
  Reply With Quote
Old 6th May 2012, 05:57 PM   #6
dbek is offline dbek  United States
diyAudio Member
 
Join Date: Feb 2012
Thank you, everyone, for your replies. And, tuxedocivic, please do let me know how you end up hooking up this driver.
  Reply With Quote
Old 20th May 2012, 05:35 PM   #7
dbek is offline dbek  United States
diyAudio Member
 
Join Date: Feb 2012
Would a notch filter benefit this speaker at all?
  Reply With Quote
Old 20th May 2012, 06:15 PM   #8
diyAudio Member
 
Scottmoose's Avatar
 
Join Date: Mar 2005
Location: UK
Depends what frequency[ies] you want to flatten / notch out.
  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
I just bought a pair of the Fostex Fe83En, And questions :) . marchel Full Range 38 5th October 2012 05:45 PM
Zobel Network Corrections fotios Solid State 11 22nd February 2007 06:03 AM
Zobel Network JiggaD369 Multi-Way 9 5th May 2005 01:27 AM
Zobel Network nuttinbutSQ Multi-Way 6 16th March 2004 09:19 AM


New To Site? Need Help?

All times are GMT. The time now is 03:44 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