EASY FIR crossover PC based+DRC - Page 4 - diyAudio
Go Back   Home > Forums > Source & Line > PC Based

PC Based Computer music servers, crossovers, and equalization

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 4th December 2012, 10:58 AM   #31
diyAudio Member
 
Join Date: Jan 2006
Location: grenoble
Quote:
Originally Posted by natehansen66 View Post
I understand that......it's getting it done that is the problem. Typically I build my eq filters in REW and copy them to the parametric eq in J River. Measurements confirm that REW's simulated eq'd response follows the actual output fairly close. On the fly changes are easy to make. The same set of filters plugged into rePHase's eq don't produce anywhere near the same result. The A + B trick gets kind of close to the actual result, but gets tiresome when you're working with 20+ filters . The eq in rePhase is a bit buggy as well, at least in the Gain Bank.
it's possible,i never test the eq bank,only use the PEQ.it's working fine.
just to get easy conscience,with FIR EQ
REW seems to be buggy too,when using import impulse and making A+B,or A/B,AxB...(normalization,impulse centering ? )


Quote:
J River says they're working on convolution latency handling for the loopback function. I've set a second zone for now with min phase filters to use the loopback, but I'm going to look into the number of taps for the filters.
i've heard something about that,but it was for previous version,(i believe MC 16 ).now,last version must be fixed i think.

Quote:
so right away I understand that's going to require more than a hi-pass at 80 would. The default 8192 taps shows a textbook roll-off and a nice continued slope as far down as the graph will go. At 5000 taps I'm getting ripple and a greatly reduced slope for the low pass starting around -100. For the 35hz high pass the slope starts transitioning to a shallower one around -40 and at 10hz -52 has transitioned to flat (no slope).

Any "rules" on whats acceptable here? I'm thinking anything greater than -50 or so wouldn't be audible at all or have any negative effect........but then I'm just guessing and like I said I don't know anything about linear phase filters.
no rules...your ears,120 dB without ripple is a little overkill.
you are right,50-60 dB won't be audible,it's up to each other.

i can use 65000 taps without issue,no loopback function is needed with virtual cable

Last edited by thierry38efd; 4th December 2012 at 11:14 AM.
  Reply With Quote
Old 4th December 2012, 11:09 AM   #32
diyAudio Member
 
Join Date: Jan 2006
Location: grenoble
Quote:
Originally Posted by Boden View Post
Bonjour Thierry,

What are the minimal PC Hardware requirements to run your setup?

Also, is the SB Audigy working satisfactory sound quality wise pr would you rather recommend a different soundcard?

Merci,

Eelco
Hello,

you can run the DRC (8000 taps stereo )+(6-8 channels 8000 taps crossover ) with a basic laptop.
modern laptop or old desktop are more powerfull than external audio hardware (dolby lake,dx46...).

i do not believe in DAC sound,whatever a correct soundcard do the job (at least 90-95 dB S/N)
mini DSP has a 85 dB ratio (measured ).
  Reply With Quote
Old 4th December 2012, 11:18 AM   #33
diyAudio Member
 
Join Date: Mar 2011
Location: Rochester, MN
Quote:
Originally Posted by thierry38efd View Post
REW seems to be buggy too,when using import impulse and making A+B,or A/B,AxB...(normalization,impulse centering ? )
Ahh......that might explain some of my problems! I'll try using Holm instead next time.
  Reply With Quote
Old 4th December 2012, 11:52 AM   #34
diyAudio Member
 
Join Date: Jan 2006
Location: grenoble
Quote:
Originally Posted by natehansen66 View Post
Ahh......that might explain some of my problems! I'll try using Holm instead next time.
try to work with .TXT files only (impulse.txt,frequency.txt)
HOLM hates .wav files,it crashes every time with seven

about target curve.
https://docs.google.com/file/d/0B97z...it?hl=en&pli=1


Click the image to open in full size.

Click the image to open in full size.


listening spot measurement at home,manual correction,7 points.(max 4 dB)

Click the image to open in full size.

Last edited by thierry38efd; 4th December 2012 at 12:15 PM.
  Reply With Quote
Old 4th December 2012, 02:50 PM   #35
pos is offline pos  Europe
diyAudio Member
 
pos's Avatar
 
Join Date: Feb 2008
Location: Paris
Quote:
Originally Posted by natehansen66 View Post
I understand that......it's getting it done that is the problem. Typically I build my eq filters in REW and copy them to the parametric eq in J River. Measurements confirm that REW's simulated eq'd response follows the actual output fairly close. On the fly changes are easy to make. The same set of filters plugged into rePHase's eq don't produce anywhere near the same result. The A + B trick gets kind of close to the actual result, but gets tiresome when you're working with 20+ filters . The eq in rePhase is a bit buggy as well, at least in the Gain Bank.
Hi

It is possible that the EQ implementation in rephase is different than the one in Jriver and REW.
There is a lot of different approches when it comes to Q interpretation in EQs (proportional, constant, etc.). Things get even worse with stuff like shelvings, where the corner frequency can be different from one implementation to another...
The EQ bank and paragraphic banks should give the exact same result, but it might be different to what Jriver, REW, or a DCX would produce.
I can try to improve this in a futur version, to mimic REW or another reference implementation more closely.

I will also probably implement an import for a measurement to be able to see the effect of the EQ (as well as filtering and phase tweaking) directly on measuremments instead of havving to use Holm or REW for the convolution.
  Reply With Quote
Old 4th December 2012, 10:47 PM   #36
diyAudio Member
 
Join Date: Mar 2011
Location: Rochester, MN
Quote:
Originally Posted by pos View Post
Hi
I will also probably implement an import for a measurement to be able to see the effect of the EQ (as well as filtering and phase tweaking) directly on measuremments instead of havving to use Holm or REW for the convolution.
Please do! I wouldn't change the way you implement the eq, but being able to see the effect in the same software would be huge.

The issues I'm having is with the Gain Bank. It only accepts + gains (by design?), and the numbers get stuck sometimes. If I mistype a value it gets "stuck" and won't change unless I clear the bank.

Other than those small issues (and my issues with J River which are being sorted) the software works quite well. I've always wanted to try linear phase but was put off by the cost of the software available so thank you for your efforts!
  Reply With Quote
Old 4th December 2012, 11:07 PM   #37
pos is offline pos  Europe
diyAudio Member
 
pos's Avatar
 
Join Date: Feb 2008
Location: Paris
The initial intent with the bank EQ section was to be able to load EQs generated by another software (like REW), but that was never implemented (I wanted to stay away from automated corrections) and now I would like to remove these bank tabs altogether, and add some more paragraphic EQ tabs to replace them...

Regarding the negative gains entered with the numerical pad, yes it is a bug I will have to correct, thanks for the report!
In the meantime you can use the up and down keys to adjust values (this is the preferred method for most of the entires, like frequency, Q, slopes, gain, etc...), and that will give you negative gains (that you will also be able to correct with the numerical pad afterward).
  Reply With Quote
Old 12th December 2012, 06:40 PM   #38
diyAudio Member
 
Join Date: Jan 2006
Location: grenoble
Default CPU load with 20 convolutions

cpu load with a basic laptop ( t4500 2 cores )
10 stereo convolutions of 8192 taps.(20 convolutions total )

the FIR crossover and FIR DRC can be done with Jriver (media center or jukebox (freeware)) and with any VST host

as we can see,any laptop is ok to do the job.

VSThost load 40%
cpu load 20 % (two cores ).

you can manage a 7.1 sytem (each tri ampified) for a total of 21 convolutions+DRC for each one with a laptop.
and a bass management (like velodyne sms 1 ) too.with high resolution in the low frequency (16000 taps ).

Click the image to open in full size.

Last edited by thierry38efd; 12th December 2012 at 06:45 PM.
  Reply With Quote
Old 12th December 2012, 07:26 PM   #39
diyAudio Member
 
Join Date: Jan 2006
Location: grenoble
same cpu (t4500 2 core laptop processor )

36 stereo convolutions of 8192 taps (72 total x 44100=26 billions ).

cpu load (VSThost use only 1 core )
91 %
Click the image to open in full size.
  Reply With Quote
Old 12th December 2012, 08:53 PM   #40
Boden is online now Boden  Netherlands
diyAudio Member
 
Join Date: Mar 2010
Dear Thierry,

Could a Pentium III machine do the job?

Kind regards,

Eelco
  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
iDFT-based XOs (FIR) steph_tsf Digital Line Level 15 5th November 2013 11:59 PM
AVX based FIR VST, crossover / EQ / DRC and delay KOON3876 PC Based 97 26th November 2012 08:18 AM
Is there any PC based software to crossover the L & R channels to the sub? spot PC Based 11 29th November 2011 12:46 PM
Looking for a New PC based Loudspeaker Crossover - What is available? mikaljones21 PC Based 9 28th June 2010 03:53 PM
Linux XO/DRC Fanless PC w. Lynxtwo jon_denmark Digital Source 6 20th July 2007 07:54 AM


New To Site? Need Help?

All times are GMT. The time now is 12:08 PM.


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