Go Back   Home > Forums > Loudspeakers > Multi-Way
Home Forums Rules Articles Store Gallery Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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 6th June 2009, 06:28 PM   #1
thadman is offline thadman  United States
diyAudio Member
 
Join Date: Dec 2005
Location: west lafayette
Default Polar Measurement setup

What are those users doing testing using for a Polar Measurement Rig? If you have pics, that would be fantastic!

Thanks,
Thadman
__________________
"It is a profound and necessary truth that the deep things in science are not found because they are useful; they are found because it was possible to find them."
  Reply With Quote
Old 7th June 2009, 11:17 AM   #2
Ron E is offline Ron E  United States
diyAudio Member
 
Ron E's Avatar
 
Join Date: Jun 2002
Location: USA, MN
If I were to make accurate polar measurements, I don't see a need for anything more complicated than a large lazy susan bearing and two sheets of plywood with degree markings every 5 degrees. They do make automated turntables and I suppose it wouldn't be terribly hard to make some PIC based motorized turntable rotator, but why?
__________________
Our species needs, and deserves, a citizenry with minds wide awake and a basic understanding of how the world works. --Carl Sagan
Science is a way of thinking much more than it is a body of knowledge. --Carl Sagan
  Reply With Quote
Old 7th June 2009, 01:22 PM   #3
diyAudio Member
 
R-Carpenter's Avatar
 
Join Date: Oct 2007
Location: Brooklyn Navy Yard
Send a message via ICQ to R-Carpenter
I use exactly that. You could get a large Lazy Susan at furniture restorers supply stores. Prob around $20.
  Reply With Quote
Old 7th June 2009, 03:03 PM   #4
doug20 is offline doug20  United States
diyAudio Member
 
Join Date: Mar 2009
Quote:
Originally posted by Ron E
If I were to make accurate polar measurements, I don't see a need for anything more complicated than a large lazy susan bearing and two sheets of plywood with degree markings every 5 degrees. They do make automated turntables and I suppose it wouldn't be terribly hard to make some PIC based motorized turntable rotator, but why?
My lazy susan/MDF was easy but its the 5 degree markings that I SUCKED AT
  Reply With Quote
Old 7th June 2009, 05:36 PM   #5
Ron E is offline Ron E  United States
diyAudio Member
 
Ron E's Avatar
 
Join Date: Jun 2002
Location: USA, MN
Well, if you wanted to get elaborate, You could get one of these:
http://www.opticsplanet.net/meade-16...elescopes.html
and use the hand controller.
__________________
Our species needs, and deserves, a citizenry with minds wide awake and a basic understanding of how the world works. --Carl Sagan
Science is a way of thinking much more than it is a body of knowledge. --Carl Sagan
  Reply With Quote
Old 7th June 2009, 05:43 PM   #6
Helmuth is offline Helmuth  Netherlands
diyAudio Member
 
Helmuth's Avatar
 
Join Date: Oct 2008
Location: Winterswijk
Place the box on a disk to make the angle. The center of the dome is the vertical ax of the rotating point.

Click the image to open in full size.

polar I think is not very informative.

Measure the whole range under a angle.
0,15 ,30, 45 degrees
Click the image to open in full size.
__________________
( (( KUGELWELLE )) )
recent projects :OB-mk1 /fatboy / monitor-xl / Horn-AM / dappolito / td124-mk1-rb301 / Hybrid-pse / Vfet
  Reply With Quote
Old 7th June 2009, 06:20 PM   #7
R.I.P.
 
Join Date: Jan 2008
Quote:
Originally posted by Helmuth
polar I think is not very informative.[/IMG] [/B]
Quite informative, actually.

You have a constant directivity beamwidth of +/- 15° there.

Tractrix, is it?
  Reply With Quote
Old 7th June 2009, 06:29 PM   #8
Helmuth is offline Helmuth  Netherlands
diyAudio Member
 
Helmuth's Avatar
 
Join Date: Oct 2008
Location: Winterswijk
Quote:
Originally posted by ZilchLab


Quite informative, actually.

You have a constant directivity beamwidth of +/- 15° there.

Tractrix, is it?
It is a mtm 13cm and 25mm dome
__________________
( (( KUGELWELLE )) )
recent projects :OB-mk1 /fatboy / monitor-xl / Horn-AM / dappolito / td124-mk1-rb301 / Hybrid-pse / Vfet
  Reply With Quote

Reply


Hide this!Advertise here!

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
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
what is bi-polar LED? gychang Parts 4 10th October 2007 04:56 PM
Help choosing measurement and modelling setup SimontY Multi-Way 65 26th April 2007 05:05 PM
Inexpensive Double Mic Setup For Low Frequency BR, TL Measurement kelticwizard Multi-Way 4 5th July 2006 11:36 PM
Can I make a Non-Polar Electrolytic using two polar ones PaulHilgeman Parts 6 10th February 2003 12:07 AM
non-polar/bi-polar...same? FBJ Solid State 4 21st June 2002 09:06 AM


New To Site? Need Help?

All times are GMT. The time now is 08:29 AM.

Page generated in 0.11007 seconds (68.08% PHP - 31.92% MySQL) with 10 queries

Copyright ©1999-2012 diyAudio