Lab horn USB crossover and general advice |
Post Reply | Page <12 |
Author | ||
snowflake
Old Croc Joined: 29 December 2004 Location: Bristol Status: Offline Points: 3122 |
Post Options
Thanks(0)
|
|
it's designed to be used in stacks of six which raises the impedance minimum slightly. most speakers have minimum impedance dips below the nominal impedance. the labhorn impedance is high enough to treat the box as a 4 ohm load for amplifiers in the band of operation 28Hz-100Hz.
that Tom Danley isn't a wally |
||
gen0me
Young Croc Joined: 20 February 2016 Location: UK Status: Offline Points: 999 |
Post Options
Thanks(0)
|
|
Thats why I pasted imp curve for 4. To lose all doubts. This horn gets even worse than usually. It has second valley so low.
Didnt read it all but impedance in horns just has this valleys. And they are worse than in brs or open air. Its just not true! I recommend 3 speakers on 2ohm channel. |
||
snowflake
Old Croc Joined: 29 December 2004 Location: Bristol Status: Offline Points: 3122 |
Post Options
Thanks(0)
|
|
how could a driver possibly have lower impedance loaded in a box than in free air?
as someone who has built and operated labhorns (as well as reading all the design process documentation and the Marshall Leach paper) this is not a real problem. they operate as 4R boxes. |
||
tv00
Old Croc Joined: 10 August 2009 Location: Denmark Status: Offline Points: 1886 |
Post Options
Thanks(0)
|
|
BPH also has this, a stack of 6 of mine are above 2 ohm impedance from 34-160hz
|
||
www.facebook.com/babysoundsystem
|
||
gen0me
Young Croc Joined: 20 February 2016 Location: UK Status: Offline Points: 999 |
Post Options
Thanks(0)
|
|
2ยท2.27ohm<5ohm You can clearly see on documentation (http://www.eminence.com/pdf/LAB_12.pdf) that free air impedance is higher than 5 ohm |
||
snowflake
Old Croc Joined: 29 December 2004 Location: Bristol Status: Offline Points: 3122 |
Post Options
Thanks(0)
|
|
well you are comparing apples and pears. simulate the lab12 driver in free air in hornresp and you will see it gives a minimum impedance of 4.33 ohms - less than the 5.26 ohms per driver when loaded on the horn. maybe that graph is wrong, or scale is in dbohms rather than ohms or something
Edited by snowflake - 29 March 2017 at 8:06pm |
||
gen0me
Young Croc Joined: 20 February 2016 Location: UK Status: Offline Points: 999 |
Post Options
Thanks(0)
|
|
Right. Looks like they added something in measurements... Nice one! |
||
Post Reply | Page <12 |
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 |