Accidental MLTL Technique - Page 23 - 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 28th August 2013, 08:20 PM   #221
GM is offline GM  United States
diyAudio Member
 
GM's Avatar
 
Join Date: Jun 2003
Location: Chamblee, Ga.
For a high Qt one it could, but need specs to check...........

GM
__________________
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
  Reply With Quote
Old 28th August 2013, 08:53 PM   #222
xrk971 is offline xrk971  United States
diyAudio Member
 
xrk971's Avatar
 
Join Date: Oct 2012
Location: Virginia
Quote:
Originally Posted by GM View Post
For a high Qt one it could, but need specs to check...........

GM
Here are the parameters

SD=532 cm2
fs=44.4 Hz - measured, factory is 47 Hz
Mms=34 g
Qms=6.00 - measured, factory is 6.69
Qes=0.635 - measured, factory is 0.51
Re=5.64 ohm - measured, factory is 5.57 ohm
Le=0.982 mH - measured, factory is 1.01 mH
Vas=161 liters
xmax = 3.5 mm

I should add that the Sd, mms, xmax, and Vas were taken from the manufacturer specs and I expect the Vas may not be accurate if the Qms and Qes varied from the spec.

I did not do the measurements - provided with the drivers.

Last edited by xrk971; 28th August 2013 at 09:16 PM.
  Reply With Quote
Old 28th August 2013, 11:25 PM   #223
bjorno is offline bjorno  Sweden
diyAudio Member
 
Join Date: Mar 2005
Location: Jacobsmountain
Send a message via MSN to bjorno
Quote:
Originally Posted by xrk971 View Post
Here are the parameters

SD=532 cm2
fs=44.4 Hz - measured, factory is 47 Hz
Mms=34 g
Qms=6.00 - measured, factory is 6.69
Qes=0.635 - measured, factory is 0.51
Re=5.64 ohm - measured, factory is 5.57 ohm
Le=0.982 mH - measured, factory is 1.01 mH
Vas=161 liters
xmax = 3.5 mm

I should add that the Sd, mms, xmax, and Vas were taken from the manufacturer specs and I expect the Vas may not be accurate if the Qms and Qes varied from the spec.

I did not do the measurements - provided with the drivers.
Hi xrk971,

Here is two attempts using your Driver targeting flat FR:

b
Attached Images
File Type: jpg xrk971-Driver.JPG (511.6 KB, 225 views)

Last edited by bjorno; 28th August 2013 at 11:30 PM.
  Reply With Quote
Old 29th August 2013, 03:34 AM   #224
xrk971 is offline xrk971  United States
diyAudio Member
 
xrk971's Avatar
 
Join Date: Oct 2012
Location: Virginia
Bjorno,
Thanks for the simulation. If I am reading your Hornresp input page correctly, this says that you suggest a 700 square inch CSA (or 22.5 in wide x 31 in deep) x 43 in long TL with a 9.3 in dia hole in 18 mm (3/4 in) thick plywood as the vent? This makes for a shorter box but the CSA is kind of big and the location of the driver is only 21 in off the floor - not close enough to ear level. But the volume is the same as I have and it does show that you are getting a flat bass response down to 28 or 29 Hz. I am not sure how to interpret your second sim - the one shown in the Mathcad sheet.
Regards,
X

Btw, here is the freq response (again), impedance, cone excursion, and impulse response for my 60 in MLTL.
Attached Images
File Type: png AMLTL-Beta12CX-Freq-1m.png (22.7 KB, 207 views)
File Type: png AMLTL-Beta12CX-Impedance.png (18.3 KB, 195 views)
File Type: png AMLTL-Beta12CX-Displ.png (17.7 KB, 189 views)
File Type: png AMLTL-Beta12CX-Impulse.png (13.0 KB, 189 views)

Last edited by xrk971; 29th August 2013 at 03:40 AM.
  Reply With Quote
Old 29th August 2013, 05:21 AM   #225
GM is offline GM  United States
diyAudio Member
 
GM's Avatar
 
Join Date: Jun 2003
Location: Chamblee, Ga.
OK, WinISD calcs 0.574 Qts, 151.73 L Vas, 9.17854 BL. Adding a ohm for speaker wiring and Qts = 0.62, making for a manly sized ~626.6 L/22.13 ft^3, 29.5 Hz Fb T/S max flat alignment. For sure, bigger than my speakers, fridge by ~2 ft^3 net.

GM
__________________
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
  Reply With Quote
Old 29th August 2013, 11:25 AM   #226
xrk971 is offline xrk971  United States
diyAudio Member
 
xrk971's Avatar
 
Join Date: Oct 2012
Location: Virginia
Thank you, GM. Confirms my suspicion of a need to use a refrigerator sized box.
But hey, the deep bass is really going to be good with a 95 to 97 dB efficiency.

One other question. With the Qts being higher, is this a good candidate for an open baffle? A CD horn in a 12 in coax in an open baffle is something I don't recall ever coming across before.

Last edited by xrk971; 29th August 2013 at 11:30 AM.
  Reply With Quote
Old 30th August 2013, 03:20 AM   #227
xrk971 is offline xrk971  United States
diyAudio Member
 
xrk971's Avatar
 
Join Date: Oct 2012
Location: Virginia
Sorry guys, I just realized I had a typo on the params I provided earlier. Also there are two drivers and they differ slightly so I averaged them out. How do you get WinISD to provide the BL and Vas based on the parameters I provided?

Here are the new averaged T/S params.
Thanks,
X


SD=532.4cm2
fs=46.1Hz
Mms=34g
Qms=5.258
Qes=0.695
Re=5.55ohm
Le=0.979mH
  Reply With Quote
Old 30th August 2013, 04:32 AM   #228
GM is offline GM  United States
diyAudio Member
 
GM's Avatar
 
Join Date: Jun 2003
Location: Chamblee, Ga.
Note the 'auto calculate' box is checked and the colors of the input values shows what's inputted Vs calculated.

GM
Attached Images
File Type: gif Eminence Beta 12CX measured [early, higher Qt].gif (14.2 KB, 47 views)
__________________
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
  Reply With Quote
Old 30th August 2013, 05:11 AM   #229
xrk971 is offline xrk971  United States
diyAudio Member
 
xrk971's Avatar
 
Join Date: Oct 2012
Location: Virginia
I did not realize I had such a limited version 0.44. I just downloaded the 'Pro' version and it has these nice features. What an upgrade!
  Reply With Quote
Old 30th August 2013, 05:15 AM   #230
GM is offline GM  United States
diyAudio Member
 
GM's Avatar
 
Join Date: Jun 2003
Location: Chamblee, Ga.
A lot more accurate overall too.

GM
__________________
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
  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
Tell us about your accidental discoveries sprinter Music 32 21st October 2013 06:22 AM
Accidental Death of a DoZ... aspringv Solid State 13 22nd July 2012 09:38 AM
Accidental DIY Audio Waterdog Introductions 9 23rd January 2012 06:31 PM
RB250 Rewiring - accidental mess up? InfiniteGain Analogue Source 5 30th January 2009 10:11 PM


New To Site? Need Help?

All times are GMT. The time now is 02:47 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