QTS/OB explanation needed - Page 4 - 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 18th May 2010, 10:00 PM   #31
GM is offline GM  United States
diyAudio Member
 
GM's Avatar
 
Join Date: Jun 2003
Location: Chamblee, Ga.
Quote:
Originally Posted by InclinedPlane View Post
I recommend avoiding drivers with a Q over 1.0 for the simple fact that the motor tends to be too weak to control the cone very well.
For a wide BW use, I agree, but (mid) woofer systems, not so much since if the correct baffle loading is chosen its roll off will damp the driver(s) somewhat.

GM
__________________
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
  Reply With Quote
Old 18th May 2010, 10:11 PM   #32
GM is offline GM  United States
diyAudio Member
 
GM's Avatar
 
Join Date: Jun 2003
Location: Chamblee, Ga.
Quote:
Originally Posted by Rudolf View Post
Forcing 70 times the energy through the low Q driver means reducing its control over the cone to the seventieth part of the original control.
Viewed another way, an OB is the inverse of a high gain TL, so as the long TL that only has the same pipe area as the driver's effective piston area (Sd) wants a strong motor (low Qts), the unfolded TL (OB) wants a proportionally weaker motor (higher Qts) and smaller baffle.

GM
__________________
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
  Reply With Quote
Old 18th May 2010, 10:12 PM   #33
diyAudio Member
 
Join Date: May 2009
Location: New Zealand
Quote:
Originally Posted by DrDeville View Post
So underdamped systems produce more bass with less power, but roll off quickly and have a resonant peak at F3. Hum hum hum--and equalization can flatten the total amount of energy, but can't stop the overhang/humming.
I think you will find that equalisation does stop the overhang/humming. The secret is to match the equalisation to the resonance. If you have, say, a 6 dB peak at 50 Hz with a Q of 1.2, then applying a 6 dB dip at 50 Hz with a Q of 1.2 will correct it, both in frequency (continuous) and time (impulse) measurements.
  Reply With Quote
Old 18th May 2010, 11:18 PM   #34
diyAudio Member
 
InclinedPlane's Avatar
 
Join Date: Jan 2007
Location: Maine
Well I should have said '.6-1.0 seems to be the range that provides the best sound to my humble ear'.
__________________
I must confess my favorite music is that made by the Rolls Royce Merlin.
  Reply With Quote
Old 19th May 2010, 01:57 AM   #35
diyAudio Member
 
Join Date: Jan 2007
Quote:
Originally Posted by GM View Post
Viewed another way, an OB is the inverse of a high gain TL, so as the long TL that only has the same pipe area as the driver's effective piston area (Sd) wants a strong motor (low Qts), the unfolded TL (OB) wants a proportionally weaker motor (higher Qts) and smaller baffle.
My head just exploded
  Reply With Quote
Old 19th May 2010, 02:48 AM   #36
GM is offline GM  United States
diyAudio Member
 
GM's Avatar
 
Join Date: Jun 2003
Location: Chamblee, Ga.
Hope it didn't hurt for long.

GM
__________________
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
  Reply With Quote
Old 19th May 2010, 04:30 AM   #37
brookbh is offline brookbh  United States
diyAudio Member
 
Join Date: Jan 2008
So after reading this read and many others on OB over the past year or so, there seems to be several basic implementations of open baffle woofers:

1) high qts drivers like the alpha 15s, goldwoods, other in-exspensive drivers
2) low fs, high sensitivity pro drivers with a q around .3 to .5, higher x-max than alpha 15s or goldwood 18,15,etc..
3) drivers like the augie or AE dipole

So here is my noob question,I have seen a few members here and other sites suggest the sigma pro 18, how would go about implementing a low q driver such as this in a standard flat open baffle?
  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
Current Mirror Explanation Needed. vdi_nenna Everything Else 33 7th July 2012 08:57 PM
Explanation for this problem? Rob11966 Tubes / Valves 4 22nd September 2007 04:39 AM
AC power connection schematic explanation needed Peter Daniel Pass Labs 20 31st July 2007 04:16 PM
Explanation of Self Oscillating Class D Genomerics Class D 19 29th October 2006 04:31 AM
CAT 5 cable explanation? Joe04 Parts 5 3rd March 2004 09:48 PM


New To Site? Need Help?

All times are GMT. The time now is 03:49 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