Loudspeaker measurement using SMAART live ? - diyAudio
Go Back   Home > Forums > Loudspeakers > Multi-Way

Multi-Way Conventional loudspeakers with crossovers

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 5th August 2009, 10:00 PM   #1
Empee is offline Empee  Netherlands
diyAudio Member
 
Empee's Avatar
 
Join Date: Sep 2006
Default Loudspeaker measurement using SMAART live ?

Hi there !

It's been a while since I've been here but I have a question
(and I have searched )

Is there anyone using SMAART Live as to measure T/S parameters of loose drivers ?

I'm trying to get it to work but none of my speakers tested so far
match the manufacturer's data.

I'm using the differential set-up as explained here

The soundcard is Sound Devices' USBPre


What I do is make a free air impedance plot,
then do a second plot with 30 gramms added to the cone,
read the data from my screen and plug it into this online calculator.


Does anybody use this method or do you have any comments on a better set-up or a different / more accurate calculation method ?


Kind regards from the Netherlands,

Empee
__________________
In the end, all is good
If it's not good, it's not the end
  Reply With Quote
Old 5th August 2009, 10:20 PM   #2
ergo is offline ergo  Estonia
diyAudio Member
 
Join Date: Mar 2001
Location: Tallinn, Estonia
Try http://www.libinst.com/praxis_downloads.htm

Praxis allows measuring impedances and calculates T/S by curve fitting method and does that also in demo mode without buying the Audpod...

Ergo
  Reply With Quote
Old 6th August 2009, 09:44 AM   #3
diyAudio Member
 
Join Date: Nov 2008
try SAT LIVE by Thomas Neumann

www.take-sat.de

navigate to the english part and the endglish forum
  Reply With Quote
Old 12th August 2009, 04:50 AM   #4
just another
diyAudio Moderator
 
wintermute's Avatar
 
Join Date: Aug 2003
Location: Sydney
Blog Entries: 22
Hi Empee. I haven't used the software you mention, but I'll make a few comments

You say that the tested speakers don't match the manufacturers data. How close a match are you expecting? You should be very surprised if they do match! There are always tolerances.

Also breakin will affect what you measure (fs should drop after breakin) but in general even though all the parameters change, the overall effect is that the (modeling) results will be the same (as all the parameters change relatively). Have you performed a breakin?

What drive levels are you using when performing the testing. Dickason recommends using the lowest drive level practical. preferably (from memory, it's been a while) you shouldn't be able to hear any sound from the speaker when you are doing the test. If you can here the MLS pulse you are probably driving it too hard. Ideally you want the level low enough that it doesn't over excite the driver, but high enough that the signal is far enough above the noise level, that you get valid data that isn't coloured by noise.

Thirdly how are you mounting the driver when performing the test? It should be firmly clamped so that it can't vibrate, in a vertical position (assuming that is how it will be mounted in the speaker) preferably with as little around it (ie in free air) as possible. It is surprising the differences in measurements that can result from adequate/inadeaquate clamping of the driver.

Anyway although I haven't answered your question, hopefully the questions I have asked may be of value.

Tony.
__________________
Any intelligence I may appear to have is purely artificial!
Some of my photos
  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
Recommendations on pc audio interface for loudspeaker measurement diypole Multi-Way 9 15th July 2009 01:45 PM
Sound card for loudspeaker measurement preiter Everything Else 8 13th August 2007 01:32 AM
Loudspeaker Quality Measurement dm1179 Multi-Way 1 14th June 2007 08:57 AM
Easy Loudspeaker Measurement System Set Up hongrn Multi-Way 3 24th July 2006 09:56 PM
Is the semiomnidirectional loudspeaker clossest to live... Bojan Hajdinjak Multi-Way 14 3rd June 2004 10:32 PM


New To Site? Need Help?

All times are GMT. The time now is 01:58 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