Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Multi-Way Conventional loudspeakers with crossovers

ARTA
ARTA
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 April 2020, 09:22 PM   #961
mbrennwa is offline mbrennwa  Switzerland
diyAudio Member
 
mbrennwa's Avatar
 
Join Date: Mar 2005
Location: Zurich, Switzerland
ARTA
Quote:
Originally Posted by Hensolo View Post
Hello. There are several measurement questions in ARTA. I am making IR measurements of several speakers in a speaker enclosure. Then to upload to VituixCAD for analysis.
1. To measure the impulse response of the speakers in the speaker housing, at what distance should the microphone be?
I put on the axis of the tweeter at a distance of 1 m from the tweeter.
2. To measure the IR of each speaker, the microphone must remain in one position? That is, on the axis of the tweeter 1m from him.
3. How to get the window on the IR chart?
I do this, but not sure what is right.
4. If you take measurements from 3 m - this is the listening point, I will get a lot of reflections. But they can not be included in the window. So maybe it’s more accurate to take measurements with 3 meters?
Since you want to use your measurements with Vituix, you'll have to understand how Vituix uses the data. The Vituix manual(s?) have some instructions, but it's not always easy to understand what's going on behind the scenes.
__________________
------
Scan waveguides (elliptical / circular) – MATAA audio analyser – Open Source Monkey Coffin
  Reply With Quote
Old 29th April 2020, 10:41 AM   #962
kimmosto is offline kimmosto  Finland
diyAudio Member
 
kimmosto's Avatar
 
Join Date: Oct 2005
Location: Kuopio
Quote:
Originally Posted by Hensolo View Post
...what...remain in one position? ...How to
See links to measurement instructions in my signature below. That is quite universal and standard method to produce measurement data at home (without large space or anechoic). Compatible with any XO simulator which does not damage timing differences in measurement data with minimum phase extraction and has simple geometry calculation with driver's origin and mic position. For example LspCAD and VituixCAD.

Last edited by kimmosto; 29th April 2020 at 10:50 AM.
  Reply With Quote
Old 30th April 2020, 06:35 AM   #964
kimmosto is offline kimmosto  Finland
diyAudio Member
 
kimmosto's Avatar
 
Join Date: Oct 2005
Location: Kuopio
^It is not needed to measure at 1 m. It's just decent compromise indoors at home to get at least 4.5 ms time window to far field measurements to get some resolution to midrange without reflections. Some diyers could have huge space, outdoors or some other anechoic to be able to measure at 2-2.5 m or with time window much longer than 4-5 ms.
This has nothing to do with -180/+180 deg wrapping of phase response. Excessive wrapping of phase response is removed by setting Reference time in FFT tool so that one of the drivers in the construction has very close to minimum phase response, and other drivers use the same Reference time to capture timing differences between the drivers. Usually Reference time is adjusted for tweeter. This is mentioned in both measurement instructions.
In my documentation ARTA just measures and saves pir files. Convert IR to FR tool in VituixCAD makes time windowing, FFT and timing offset for pir files, and Merger tool combines near field and far field measurements (or far field and far field).
  Reply With Quote
Old 30th April 2020, 11:02 AM   #965
Hensolo is online now Hensolo
diyAudio Member
 
Join Date: Jan 2020
Quote:
Excessive wrapping of phase response is removed by setting Reference time in FFT tool
Where is the FFT tool located? How to set the reference time?
I take a FR2 measurement in ARTA, then through the 'Recorder' I look at the delay time. Then I switch to IR. I set the delay from FR2. I take a measurement. Then, from the first peak of the impulse, I count the delay back and put the cursor. After the end of the impulse with a max peak, I put a marker so that I get the required number of samples.
If ARTA has the correct delay value, it must draw the correct graph. Here you can make the gate larger. So that there is a minimum number wrapping of phase. Are you doing another?
  Reply With Quote
Old 30th April 2020, 12:17 PM   #966
kimmosto is offline kimmosto  Finland
diyAudio Member
 
kimmosto's Avatar
 
Join Date: Oct 2005
Location: Kuopio
Quote:
Originally Posted by Hensolo View Post
Where is the FFT tool located? ...
Tools -> Convert IR to FR.

Measurements with ARTA, beginning on page 7.

User manual, pages 50-52.
  Reply With Quote
Old 30th April 2020, 02:50 PM   #967
Hensolo is online now Hensolo
diyAudio Member
 
Join Date: Jan 2020
I read the instructions. I understood almost everything, but it takes time to try. If I clicked 'Get Ref. Time', how to undo it? Or how to take a step back? When I do IR in ARTA, is it not necessary for me to get the delay value first?
And again about the distance from the microphone to the speaker. I have 4 speakers + port. To make the correct measurements of the far field, it is need to put the microphone at a height of the middle of the tweeter at a distance of 1 m and from this point to measure all the speakers? And then in Vituix, enter the vertical offset for the three speakers except tweeter? Or measure each speaker at its height at a distance of 1 m and then do not enter their vertical offset from the tweeter?
  Reply With Quote
Old 3rd May 2020, 11:22 AM   #968
kimmosto is offline kimmosto  Finland
diyAudio Member
 
kimmosto's Avatar
 
Join Date: Oct 2005
Location: Kuopio
Could someone else find, copy and paste from already written instructions. I'm quite busy and tired to repeat the same.
  Reply With Quote
Old 3rd May 2020, 08:23 PM   #969
ScottG is offline ScottG  United States
diyAudio Member
 
Join Date: Feb 2003
Location: US
^ I'm surprised you've provided this much support for a product that you didn't produce.

-and not once received a THANK YOU!



I'll say it though: thank you Kimmosto.
__________________
perspective is everything
  Reply With Quote
Old 4th May 2020, 07:38 PM   #970
kimmosto is offline kimmosto  Finland
diyAudio Member
 
kimmosto's Avatar
 
Join Date: Oct 2005
Location: Kuopio
^You're very welcome!
Best to support few common programs as long as I don't make my own.
  Reply With Quote

Reply


ARTAHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Arta box. miklos Equipment & Tools 2 19th September 2014 07:27 PM
Help with Arta- HOLMImpulse viki_v2 Software Tools 2 12th September 2012 02:04 AM
arta vs cliowin ermes Multi-Way 0 4th March 2011 02:37 PM
ARTA - using ARTA to measure room acoustics! OMF Software Tools 0 25th November 2009 01:55 PM
ARTA help Cousin Billy Multi-Way 2 13th February 2009 12:16 AM


New To Site? Need Help?

All times are GMT. The time now is 02:58 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Copyright ©1999-2020 diyAudio
Wiki