Hf horn design |
Post Reply | Page 12> |
Author | |
gen0me
Young Croc Joined: 20 February 2016 Location: UK Status: Offline Points: 999 |
Post Options
Thanks(0)
Posted: 13 June 2017 at 1:13pm |
Any idea how to get ts parameters of hf drivers?
Producents dont publish them. Yyou cant measure them adding mass to membrane. You cant measure it by free air measurement and in volume as they have closed rear. Are there some standard parameters for bullets, 0,75" 1" and so on? Edited by gen0me - 13 June 2017 at 1:20pm |
|
bass*en*mass
Old Croc Joined: 03 September 2009 Location: "unknown" Status: Offline Points: 4009 |
Post Options
Thanks(0)
|
another "advanced" question there..
|
|
gen0me
Young Croc Joined: 20 February 2016 Location: UK Status: Offline Points: 999 |
Post Options
Thanks(0)
|
Sorry
I found some example for 2" in abec but its noname. The only thing that comes to my mind is to check drivers response on 2 different horns and try to adjust parameters. First 3d scan those horns.. Is there really any way to simulate driver up to 20k? How companies do it? Try and error? Edited by gen0me - 13 June 2017 at 8:32pm |
|
bass*en*mass
Old Croc Joined: 03 September 2009 Location: "unknown" Status: Offline Points: 4009 |
Post Options
Thanks(0)
|
for horn simulations, which are what you likely looking for, you wont need the driver specs afaik as most are simply relying on ideal cone/diaphragm behaviour and just show the horn response, re drivers, you could measure those without a horn to get an idea of their "natural" response, or just compare published graphs, with a pinch of salt (basically it mainly depends on diaphragm size and material, compression ratios and throat arangement + horn geometry afaik) - details depend on what you want to achieve..?! remember the horn doesnt end where the horn flare ends/all depends on your specific driver and its internal geometry+ideal coupling to the flares within reason.. simply put.. not an expert by far at all but thats what i concluded..
|
|
gen0me
Young Croc Joined: 20 February 2016 Location: UK Status: Offline Points: 999 |
Post Options
Thanks(0)
|
I made some sims in hornresp taking as base parameters from abec. Sd ~15, bl 5, cms 1e-5, rms 4, mms 0.5, Le 0.1, Re 6.7. And I got what I was looking for. Looks like top of the bandwidth doesnt depend almost at all from horn. At least normalized char. It depends mostly from Mms and Bl of a driver.
|
|
PavelP
Registered User Joined: 25 March 2011 Location: Russia Status: Offline Points: 159 |
Post Options
Thanks(1)
|
Elliot Thompson
Old Croc Joined: 02 April 2004 Location: United States Status: Offline Points: 5172 |
Post Options
Thanks(0)
|
You can measure the TS Parameters of a Compression Driver using ARTA/LIMP. There is no need to add mass to the membrane as the driver is sealed. You can attain the fs, QMS, QES in addition to the QTS using ARTA/LIMP Best Regards, Edited by Elliot Thompson - 25 June 2017 at 7:59pm |
|
Elliot Thompson
|
|
studio45
Old Croc Joined: 16 October 2007 Location: United Kingdom Status: Offline Points: 3863 |
Post Options
Thanks(0)
|
So would you use the standard LIMP sealed box method to do that, ie take one impedance sweep with the compression driver throat open to the air and then another with it mounted onto the box, firing inwards?
Given that the volume in the driver throat is difficult to calculate due to complex shapes, I suppose you need to use a comparatively large test box to minimise that error?
|
|
Studio45 - Repairs & Building Commotion Soundsystem -Mobile PA
|
|
Elliot Thompson
Old Croc Joined: 02 April 2004 Location: United States Status: Offline Points: 5172 |
Post Options
Thanks(0)
|
Yes. Like cone loudspeakers, Compression drivers should be measured in free air as there is no limitation based on the enclosure size or Horn assembly. You can make a second measurement with the horn assembly attached to the compression driver and compare the TS Parameters of the compression driver attached and detached from the horn assembly. There is no sound escaping from the rear of the compression driver so you do not need a box. The horn assembly acts like a box as far as the compression driver is concerned. Best Regards, Edited by Elliot Thompson - 26 June 2017 at 3:20pm |
|
Elliot Thompson
|
|
PavelP
Registered User Joined: 25 March 2011 Location: Russia Status: Offline Points: 159 |
Post Options
Thanks(0)
|
Elliot Thompson, there's no 'horn' option in Limp, only closed box volume, so all the data you gain will be useless. And btw horn don't really acts as closed box. The only variant is to bigger rear chamber volume of the driver for the second measurement.
|
|
Elliot Thompson
Old Croc Joined: 02 April 2004 Location: United States Status: Offline Points: 5172 |
Post Options
Thanks(0)
|
You are not reading what I wrote correctly. You are measuring the driver in Free Air. Best Regards, |
|
Elliot Thompson
|
|
PavelP
Registered User Joined: 25 March 2011 Location: Russia Status: Offline Points: 159 |
Post Options
Thanks(0)
|
Sorry, english is not my native language.
Without back chamber you mean? |
|
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 |