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

A Study of DML's as a Full Range Speaker
A Study of DML's as a Full Range Speaker
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 7th April 2020, 07:01 PM   #1711
bradleypnw is offline bradleypnw
diyAudio Member
 
Join Date: May 2019
Quote:
Originally Posted by davelang View Post
Donít you have to mike the speakers or room? Whatís to stop a ambient noise from getting into the feedback loop?
The speaker and mic are both controlled by REW.
  Reply With Quote
Old 7th April 2020, 07:09 PM   #1712
davelang is offline davelang  United States
diyAudio Member
 
davelang's Avatar
 
Join Date: Nov 2007
Location: South Dakota
A Study of DML's as a Full Range Speaker
Donít want to beat a dead horse but say you have a 60 cycle rumble in your house and a 60 cycle signal coming from your siggen out to the speakers - how does the program know what component of that signal amplitude is from what source?
  Reply With Quote
Old 7th April 2020, 07:42 PM   #1713
intaud is offline intaud  United States
diyAudio Member
 
Join Date: Jan 2020
Location: New York
Quote:
Originally Posted by davelang View Post
Donít want to beat a dead horse but say you have a 60 cycle rumble in your house and a 60 cycle signal coming from your siggen out to the speakers - how does the program know what component of that signal amplitude is from what source?
I use a USB measurement mic from MiniDSP. It comes with a calibration file which REW uses in its measurements. The idea is to have your measurement signal from about 1m around 80dB which should be well above the noise floor. The low end is always difficult due to influences from the room. REW is a great tool and FREE.

Thanks, Dave
  Reply With Quote
Old 7th April 2020, 07:48 PM   #1714
tagis is offline tagis  United States
diyAudio Member
 
Join Date: Feb 2020
Location: Colorado
Hi Dave, When making the REW measurements the program does see the ambient noise along with the signal coming from the signal so one tries to keep it quite or should.

I have been playing around with the exciter response since the impedance is not constant across the frequency band. So one does not have equal power across the frequency band. If your amplifier is flat or constant gain and using the equation P= V^2/R one sees how the power varies across the frequency. I have been using a two prong approach where I use a DSP Power amp. ( where I model out the impedance of the exciter) and then a DSP filter to flatten out the speaker response .

This give a very good audio response . I have all my friends who are in various local jazz groups over (before Covid-19 lock down) and they all are all so impressed. They can not believe the sound that the system produces it is a transcendental experience the closest to having the musicians there.....
Cheers
Steve
  Reply With Quote
Old 7th April 2020, 08:09 PM   #1715
davelang is offline davelang  United States
diyAudio Member
 
davelang's Avatar
 
Join Date: Nov 2007
Location: South Dakota
A Study of DML's as a Full Range Speaker
Thank you bradleypnw, intaud, and tagis!

I think I get it. The system records ambient noise as part of its calibration file and then somehow subtracts it from the sound from a calibrated sound file and then outputs to the speakers a corrected signal to flatten and smooth the final sound output.

I just downloaded the software... I need to stop blathering... Thanks for helping me understand. Truly appreciated.
  Reply With Quote
Old 8th April 2020, 01:47 AM   #1716
gapmedia is offline gapmedia  Australia
diyAudio Member
 
gapmedia's Avatar
 
Join Date: Jun 2006
It is best to try and have your background noise as low as possible when testing, as REW hears everything during the measurment, and includes it. I don't think REW takes into account/subtracts other noises and room reflections happening in your room at the time, it just records them all along with your speakers' output. This is why anechoic chambers are best for testing, and probably why JBL(?) used to test their systems outside and 40 feet in the air, on a quiet day I presume. REW is a very complete system, with lots to learn. Have fun!

Last edited by gapmedia; 8th April 2020 at 02:08 AM.
  Reply With Quote
Old 8th April 2020, 02:17 AM   #1717
bdjohns is offline bdjohns  United States
diyAudio Member
 
Join Date: Feb 2010
Location: Iowa
Quote:
Originally Posted by gapmedia View Post
It is best to try and have your background noise as low as possible when testing, as REW hears everything during the measurment, and includes it. I don't think REW takes into account/subtracts other noises and room reflections happening in your room at the time, it just records them all along with your speakers' output. This is why anechoic chambers are best for testing, and probably why JBL(?) used to test their systems outside and 40 feet in the air, on a quiet day I presume. REW is a very complete system, with lots to learn. Have fun!
On HolmImpulse you can select a "noise" graph. I have assumed that that response is anything that was not part of the original test signal, that it was either ambient or created by the speaker. The noise usually is near the level of the harmonic distortion graph.
  Reply With Quote
Old 8th April 2020, 02:29 AM   #1718
bradleypnw is offline bradleypnw
diyAudio Member
 
Join Date: May 2019
In my case I: sweep then equalize, sweep then equalize, sweep then equalize, ad infinitum. If any background noise showed up in one sweep it would be gone in the next.
  Reply With Quote
Old 8th April 2020, 04:03 AM   #1719
gapmedia is offline gapmedia  Australia
diyAudio Member
 
gapmedia's Avatar
 
Join Date: Jun 2006
Quote:
Originally Posted by bradleypnw View Post
In my case I: sweep then equalize, sweep then equalize, sweep then equalize, ad infinitum. If any background noise showed up in one sweep it would be gone in the next.
Hi bradleypnw. Are you using REW for the above? I'm not (that) familiar with HolmeImpulse if you're using that, as 'dbjohns' mentioned. I tend to use REW for measurements, DRCDesigner to play with DSP/DRC, and then playback through JRver to test measurements and implement any DSP/DRC. Not saying these are the best software to use, just don't cost that much (some free) and work well for me.

I have started to look into room diffusers and bass traps, but these really have a low WAF. But in the end, would probably, in terms of performance increase be worth the grief.
  Reply With Quote
Old 8th April 2020, 04:38 AM   #1720
gapmedia is offline gapmedia  Australia
diyAudio Member
 
gapmedia's Avatar
 
Join Date: Jun 2006
Quote:
Originally Posted by spedge View Post
I have the same sound track of walking on the moon,and was wondering if I could use my phone to make a comparison,but what about royalties and the like? Do you upload the same as a picture?
I'm willing to give it a try.
Recordings I've made of church organs on my phone have sounded ok ,as long as you take the acoustics into account.
Even if the recording doesn't sound great,it does give an idea of what to expect
Just a thought
Steve
Hi Steve. For these files I recorded the audio into my laptop and exported from a video editing program as mp4's with no picture. There are, I'm sure, other ways to create audio only mp4's. mp4 seems to be the only uploadable format allowed on this forum for A/V files, other than zipping other formats, but then only to 3.18meg in size.

My way of looking at it is who would want my DML recordings in their music collection, and a lot of the music I have purchased and now listen to is due to exposure from this site and others like it.
  Reply With Quote

Reply


A Study of DML's as a Full Range SpeakerHide 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
Full Range Voice Range single speaker and enclosure loninappleton Full Range 23 8th May 2014 11:14 PM
Proposal for a full range speaker radio Full Range 20 23rd April 2014 05:03 PM
Design Study: Full Range Line Array Dumbledog Multi-Way 5 27th October 2013 12:45 PM
Full range speaker package. perceptionchanges Swap Meet 1 15th July 2013 03:08 AM
Full range active speaker zebra100 Full Range 10 24th August 2009 11:28 AM


New To Site? Need Help?

All times are GMT. The time now is 07:22 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