Test tones for listening tests - diyAudio
Go Back   Home > Forums > Loudspeakers > Full Range

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 20th January 2008, 08:38 PM   #1
diyAudio Member
 
Join Date: Feb 2004
Location: Appleton, WI
Default Test tones for listening tests

I have some test tones which were downloaded from an mp3 source.

The thing I noticed in the lower and lowest freq tests was:

1.) lots of Xmax activity by the driver itself

2.) some tone change as the sound played. The only analog I can think of is a transmission change in a car like the speaker was 'warming up' and changing pitch without changing the frequency on the player setting.


I cannot ascribe it to my hearing. It seems to be a mechanical thing.
  Reply With Quote
Old 20th January 2008, 10:46 PM   #2
jnb is offline jnb  Australia
diyAudio Member
 
Join Date: Dec 2006
Is it a multiple test tone?

I haven't used an mp3 tone but I wouldn't. Have you tried noise based testing... Arta, for example?
  Reply With Quote
Old 21st January 2008, 12:23 AM   #3
diyAudio Member
 
Join Date: Feb 2004
Location: Appleton, WI
Is this a digital source?

I was just using free stuff and do not have things like a scope and tone generation equipment.
  Reply With Quote
Old 21st January 2008, 12:28 AM   #4
jnb is offline jnb  Australia
diyAudio Member
 
Join Date: Dec 2006
I hope there's no misunderstanding. Arta (computer program) will generate its own test tones. All you need is a mic.
  Reply With Quote
Old 21st January 2008, 04:12 AM   #5
diyAudio Member
 
Join Date: Feb 2004
Location: Appleton, WI
Ok, I know a bit about this sort of software but not much.

Maybe some day I will be able to do testing. I thing audiorountable had some info on this but I don't really know where the how to would be covered.
  Reply With Quote
Old 21st January 2008, 04:58 AM   #6
hermanv is offline hermanv  United States
diyAudio Member
 
Join Date: Apr 2004
Location: Northern California
IMHO Test tones are valuable for measuring frequency response, impedance maybe 2nds and 3rds, but utterly worthless for listening tests.

At a loud enough levels, sine wave tones will heat voice coils or crossover components in a way that music never will. So the sound changes over time as things get hot.
  Reply With Quote
Old 21st January 2008, 05:36 AM   #7
diyAudio Member
 
Richard Ellis's Avatar
 
Join Date: Sep 2006
Location: Mar del Plata, a BIG seasonal getaway city, can see the Ocean from our residence.
Default Test tones

Test tones can test for enclosure integrity...some years ago a buddy of mine who was in the DJ business neede his speakers rebuilt,,,we changed drivers for a more balanced (Accurate) response & made a new enclosure. We did an A-B test at thirty hertz with the old against the new...the old set was merely vibrating the enclosure to death complete with air-leaks, resonances, and harmonics.
The old set would not propagate the low frequency,,,the new one on the otherhand set the windows in motion quite well.
____________________________________Rick..........
  Reply With Quote
Old 22nd January 2008, 01:23 PM   #8
diyAudio Member
 
happy.gringo's Avatar
 
Join Date: Sep 2005
Was the speaker you tested a fullrange? I have heard similar "transmission changes" when I played with a 2 way crossover, which I assumed were phase problems, but I really don't know. I use this freeware signal generator and it did help alot in setting the tweeter level:
http://www.natch.co.uk/downloads/SigJenny/SigJenny.html
  Reply With Quote
Old 22nd January 2008, 08:52 PM   #9
diyAudio Member
 
Join Date: Feb 2004
Location: Appleton, WI
Nope just single FE127e.


The test tones gave so much excusion I thought the
surround was going to fly off.


The sound is sort of like a balloon being flapped by a bicycle wheel.

I have another test going today with less batting inside and covering just 2 walls.
  Reply With Quote
Old 23rd January 2008, 01:36 AM   #10
hermanv is offline hermanv  United States
diyAudio Member
 
Join Date: Apr 2004
Location: Northern California
Quote:
Originally posted by loninappleton
<snip>
The test tones gave so much excursion I thought the
surround was going to fly off.

The sound is sort of like a balloon being flapped by a bicycle wheel.

I have another test going today with less batting inside and covering just 2 walls.
In most enclosure designs the air in the chamber acts as a spring against the cone. In a ported design, the enclosure spring disappears below the port resonance frequency. At or below this frequency the woofer cone is un-damped, causing it to flop about kind of like a balloon being flapped by a bicycle wheel.

Don't test woofers blow their cutoff point, it provides no information and can damage the woofer. Do not operate woofers beyond the Xmax rating, either by too low a frequency or too high a drive level.
  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
Listening tests Rob M Everything Else 119 26th January 2014 08:40 AM
Test tones edjosh23 Everything Else 13 29th December 2004 04:04 PM
Test Tones Jye Multi-Way 3 17th May 2004 02:27 AM
test tones on CD? millwood Solid State 27 19th December 2003 09:21 AM
Computer generated test tones Pete Fleming Multi-Way 2 31st October 2001 01:39 AM


New To Site? Need Help?

All times are GMT. The time now is 04:27 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