Equal Loudness Contour filter with MiniDSP. Can be done? - Page 4 - diyAudio
Go Back   Home > Forums > Commercial Sector > Manufacturers > miniDSP

miniDSP Low cost, modular Digital Signal Processor (DSP) kits for the DIYer from miniDSP.

Reply
 
Thread Tools Search this Thread
Old 16th December 2013, 08:09 AM   #31
diyAudio Member
 
Join Date: Apr 2007
I just bought a 2x8 and I have been trying to figure out if any progress has been made on this? It seems like such a simple thing to implement.
__________________
Simplicity is elegance.
DIY=Sticken It To The Man
  Reply With Quote
Old 24th April 2014, 09:32 PM   #32
diyAudio Member
 
Join Date: Dec 2013
Same here, anyone knows if this is dead or implemented differently by miniDSP? (having the disappointment of a nice curve with REW and 2x4 at ~90dB, but 2 small ones sleeping making the listening at ~60dB pretty bad at evenings (especially basswise)
  Reply With Quote
Old 24th April 2014, 10:39 PM   #33
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Hi,

If you want a spanner in the works I can throw you several :

a) The FM curves are equal loudness related to fixed levels
at 1KHz. Whilst it is clear in those curves response to levels
varies at different frequencies, by necessity they include the
ludicrous assumption @ 1KHz ear response to relative levels
is perfectly linearly logarithmic.

b) So FM curves don't tell you how loud it actually is, and
annoyingly I've never seen an attempt to quantify the
perception of different levels @ 1KHz.

c) If your confused say move the the reference point to
3KHz and assumed that is perfectly linearly logarithmic.
The curves will change but won't tell you any more *.

d) IMO you cannot assume any frequency is in any
way is perfectly linearly logarithmic, much to my
frustration in the way F&M information is presented.

e) So if you have twigged F&M curves show equal
loudness curves relative to completely arbitrary
levels at 1KHz, they don't tell you how loud it is.

rgds, sreten.

* But wiil change what you can read into the spacing.
__________________
There is nothing so practical as a really good theory - Ludwig Boltzmann
When your only tool is a hammer, every problem looks like a nail - Abraham Maslow

Last edited by sreten; 24th April 2014 at 10:43 PM.
  Reply With Quote
Old 25th April 2014, 01:58 AM   #34
diyAudio Member
 
Join Date: Jun 2003
Location: Hamilton, was Ottawa (Canada)
80 year update!


ISO 226:2003 (/2008)
Acoustics -- Normal equal-loudness-level contours

Abstract

This International Standard specifies combinations of sound pressure levels and frequencies of pure continuous tones which are perceived as equally loud by human listeners. The specifications are based on the following conditions: the sound field in the absence of the listener consists of a free progressive plane wave; the source of sound is directly in front of the listener; the sound signals are pure tones; the sound pressure level is measured at the position where the centre of the listener's head would be, but in the absence of the listener; listening is binaural; the listeners are otologically normal persons in the age range from 18 years to 25 years inclusive.

ISO 226 2003.jpg

See this great thread at ... the grumpy place:
http://www.diyhifi.org/forums/viewto...+curves#p47818
  Reply With Quote
Old 3rd May 2014, 04:25 PM   #35
diyAudio Member
 
otto88's Avatar
 
Join Date: Dec 2007
Quote:
Originally Posted by minidsp View Post
To all,

Sorry for the late reply. We weren't ignoring all the good comments and ideas.

[B]The idea is indeed very good.[B]
With miniDSP, [B]we indeed have the ability[B] to implement a simple Loudness control using the well known Fletcher and Munson curves.

Not much work apart from programming the features, adding and toggle for the external control potentiometer (from volume to loudness). Then adding some controls in the UI for selecting the high and low freq.

A good idea that we'll try to implement in the future.

DevTeam.

Dear Dev Team

We're patient, but it's now been three and a half years . .
Where does this very popular, not much work plug-in fit in your plans?

Thanks

Otto
  Reply With Quote
Old 3rd May 2014, 05:55 PM   #36
Davey is offline Davey  United States
diyAudio Member
 
Join Date: Dec 2001
Location: Bremerton, WA.
If I were miniDSP I would put this at the bottom of my to-do list.

And I don't think it's as simple to implement as everyone might think. You're talking about a continuous level-sensing EQ that modifies the shelving actively at various levels. Plus, you'd need to have the capability to threshold "calibrate" it some way for various speaker efficiency, amplifier voltage gain, source level, etc, combinations.

This is not trivial....IMHO.

A user could easily set up a simple shelving filter with the existing hardware and switch it on/off manually. This would be much the same as a traditional "loudness" switch/control that might have been found on equipment from decades past. I think that would achieve 90% of the goal here.....IMO.

Some of the other DSP platforms have forms of "dynamic" EQ, although I don't like the way those work and it's not, strictly speaking, the same as the request here.

Cheers,

Dave.

Last edited by Davey; 3rd May 2014 at 06:06 PM.
  Reply With Quote
Old 3rd May 2014, 07:02 PM   #37
diyAudio Member
 
otto88's Avatar
 
Join Date: Dec 2007
Ideally it would be a continuous level-sensing EQ that modifies the shelving actively at various levels.

But might there be something in between the complexity of that ideal, and two (treble and bass) simple shelving filters?
  Reply With Quote
Old 6th May 2014, 02:27 PM   #38
JohnR is offline JohnR  Australia
diyAudio Member
 
Join Date: Dec 2001
Location: Steak and Kidney
I'm with Davey... I mean, it would be very cool to have some sort of Labview-like DSP programming visual language to enable these kinds of things, but I can only imagine the development and support costs (having been there, somewhat).

If you want different EQ configurations, just set them up with one of the platforms that allows it and switch with a remote. You don't need infinitely-variable loudness contours, two or three would do it, surely?
  Reply With Quote
Old 6th May 2014, 04:00 PM   #39
diyAudio Member
 
otto88's Avatar
 
Join Date: Dec 2007
Quote:
Originally Posted by JohnR View Post
You don't need infinitely-variable loudness contours, two or three would do it
Yes, I now see that infinitely-variable is a lot of complexity.
2-3 would help. Better than one!

I was going to use one setting for a mild midbass hump.
It'd be nice to have a setting with both a midbass hump, and (for listening at lower volumes) a "loudness contour".
of course the "standard" setting
And I have a *lot of difficulty with the intelligibility of dialog. A setting that emphasises consonants, about 2-5 kHz - I would find that very useful for anything spoken (and possibly song lyrics) etc

I'm no EE, but wonder what part of the miniDSP limits the number of settings currently to a total of four. Memory?

What's most important is to get an "excellent"/ "smooth" crossover.
But then, to be able to tune it to say 3 different sorts of material/ volume?
That would be icing on the cake. I'd be happy to pay some extra, for some extra flexibility.
  Reply With Quote
Old 6th May 2014, 04:12 PM   #40
Davey is offline Davey  United States
diyAudio Member
 
Join Date: Dec 2001
Location: Bremerton, WA.
"Loudness" compensation in playback equipment has always puzzled me since I think the ear/brain adjusts for this automatically. When I go to the Seattle Symphony does the orchestra need to "equalize" their sound when playing softly vice full force? Everything we hear in nature is not equalized depending upon absolute SPL.

Dave.
  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
First Speaker, trying to figure out a contour filter SState13 Full Range 7 9th September 2009 12:10 AM
contour/notch filter for Fe208e sigma? adamt Full Range 1 16th April 2009 02:15 PM
Preamp with Loudness compensation and Subsonic filter quicknick Solid State 7 7th April 2009 05:16 PM
Equal-Loudness-Curves / Fletcher-Munson / ISO 226 / etc. - WHY do we care? smellygas Multi-Way 29 25th February 2009 04:11 PM
Equal-Loudness Curves for low frequencies? Sjoerd v L Subwoofers 4 9th June 2005 10:22 PM


New To Site? Need Help?

All times are GMT. The time now is 08:28 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