|
What I am doing wrong ? |
Post Reply 
|
| Author | |
3sky 
Registered User 
Joined: 05 July 2008 Location: slovakia Status: Offline Points: 21 |
 Post Options
 Thanks(0)
 Quote Reply
 Topic: What I am doing wrong ?Posted: 17 June 2016 at 2:53pm |
|
When I simulate manufacturer recommended enclosure for BMS 12N630 ,I am getting completely different tuning frequency.(and high x-max) Why is that ? Are my ts parameters wrong ?
I have also simulated Tony Wilkes Q12 box and it gave me air velocity of 45 m/s.   Edited by 3sky - 17 June 2016 at 3:08pm |
|
 |
|
|
LunchieTey
Young Croc 
Joined: 06 February 2005 Location: Australia Status: Offline Points: 934 |
Post Options
Thanks(0)
Quote Reply
Posted: 17 June 2016 at 3:40pm |
|
Some enclosures(even name brand) have mechanical power limits BELOW their thermal limits. Also MUSIC often makes less cone excursion than pure sinewaves so a couple of mm on a driver like this will not be the end of the world(not always the case though so be careful)
Also from what I read, Tony tuned the Q12(double woofer version) to 45hz not 38 and it was 70L (35 per driver) and you have 44(which will mean more excursion for you. Try it again at 35L and 45hz.
|
|
|
Speaker addict
|
|
|
|
|
Meat
Old Croc 
Joined: 05 June 2009 Location: Manc Status: Offline Points: 1514 |
Post Options
Thanks(0)
Quote Reply
Posted: 17 June 2016 at 3:43pm |
|
Tony frequently used slightly undersized (compared to the simulations) ports in his designs in order to minimise enclosure size. As I understand they were tested and if there wasn't a problem they stayed like that.
|
|
|
Don't test the champignon sound
|
|
|
|
|
3sky
Registered User
Joined: 05 July 2008 Location: slovakia Status: Offline Points: 21 |
Post Options
Thanks(0)
Quote Reply
Posted: 17 June 2016 at 5:44pm |
|
35 L box with port size of 100x215 (from Q12 plan) gives me tuning of 48Hz and air velocity 42 m/s
I think the tuning is OK . Tony wrote in one post that the fact that end of the port is very close to drivers magnet lowers the tuning frequency a little bit.So in realty it might be 45Hz. But the air speed seems very fast.What do you normally take to be highest limit for air velocity ? I am sure that Q12 works perfect.I just think I might be making some mistake when working with WinISD which makes my simulations inaccurate.
Edited by 3sky - 17 June 2016 at 6:04pm |
|
|
|
|
3sky
Registered User
Joined: 05 July 2008 Location: slovakia Status: Offline Points: 21 |
Post Options
Thanks(0)
Quote Reply
Posted: 17 June 2016 at 6:03pm |
|
This is the 60L box. Tuning is actually close enough.But excursion seems very large (5,5 mm over drivers xmax).
 |
|
|
|
|
LunchieTey
Young Croc
Joined: 06 February 2005 Location: Australia Status: Offline Points: 934 |
Post Options
Thanks(0)
Quote Reply
Posted: 17 June 2016 at 6:35pm |
|
Well bigger boxes and lower tuning mean MORE excursion.
What did you expect? And remember, MUSIC is different to TEST TONES so don't stress over small differences.
|
|
|
Speaker addict
|
|
|
|
|
3sky
Registered User
Joined: 05 July 2008 Location: slovakia Status: Offline Points: 21 |
Post Options
Thanks(0)
Quote Reply
Posted: 17 June 2016 at 8:17pm |
|
Thank you
I dont have much experience ,that is why I thought the differences are big. So it looks like I have the software set up correctly.I want to build small and loud sub with even higher tuning that Q12. Most commercial P.A 12 inch subs have steep peak aground 65 Hz(or even higher). What do you think of this ?  Edited by 3sky - 17 June 2016 at 8:18pm |
|
|
|
|
bee
Old Croc
Joined: 14 June 2011 Location: Middlesex Status: Offline Points: 4553 |
Post Options
Thanks(0)
Quote Reply
Posted: 17 June 2016 at 9:52pm |
correct re port, this was what led to the q18fp design, using port assisted alignment to driver, and the b6 loading design.
|
|
|
https://www.elements-audio.com
|
|
|
|
|
bee
Old Croc
Joined: 14 June 2011 Location: Middlesex Status: Offline Points: 4553 |
Post Options
Thanks(0)
Quote Reply
Posted: 17 June 2016 at 9:55pm |
|
port tuning of the q12 was 43hz, this allows the box to play +-3db at 35 hz.
|
|
|
https://www.elements-audio.com
|
|
|
|
|
Post Reply
|
|
| Tweet |
| Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |
Topic Options
3sky wrote: