rePhase, loudspeaker phase linearization, EQ and FIR filtering tool

[jmbee]

HI Rvrazvan, i made a short description of my simple way to use RePhase as phi équalizer in Foobar (with foo-convolve.)
in French, but may help i hope.

crd
Egalisation fir avec RePhase - Le blog de jimbee

[pos]

Hi jmbee

Yes, your tutorial is more in line with what Rvrazvan seems to be looking for!
Especially the second part, "Test avec filtre iir standard L-R. trois voies", as the first part is dealing with a system that is already quite linear in phase (using a modified DCX2496 for substractive filtering)

By the way, when using the foobar convolver plugin, it is best to uncheck the "Auto level adjust" checkbox.

[ra7]

has some one figured out a proper ABX procedure for testing this? I'm afraid I may be halucinating with all the positive changes I'm hearing

[thierry38efd]

Can you switch the plugin during listening ?

A specific attention is needed to exactly match the level with or without convolution .
0.5 dB less or more and test is not decisive .

(play a sine at 1 KHz and bypass convolver to adjust level.)

[ra7]

I don't think bypassing the convolver is a good idea. I generated an impulse that makes no correction and use it as the alternate to the 'fixed' impulse. So, the convolver runs for both the cases.

The big thing is not knowing what is being played when you do the listening.

How about this:
1. Play a song in Foobar with the corrected impulse and record the output of the soundcard.
2. Play the same song with uncorrected impulse with convolver running perfect impulse and record output of soundcard.
3. Play both recorded files through speakers using the ABX plugin in Foobar.

Will this capture the change correctly?

[thierry38efd]

I don't think bypassing the convolver is a good idea. I generated an impulse that makes no correction and use it as the alternate to the 'fixed' impulse. So, the convolver runs for both the cases.

this is the simplest way to adjust level.
time to switch "flat impulse" to "corrected impulse" do not allow an accurate setting.
auditive memory is not required,when bypassing on the fly.

How about this:
1. Play a song in Foobar with the corrected impulse and record the output of the soundcard.
2. Play the same song with uncorrected impulse with convolver running perfect impulse and record output of soundcard.
3. Play both recorded files through speakers using the ABX plugin in Foobar

yes,you can convolve "offline" and record.
why don't use multiple instance of foobar instead ? play/pause for each instance.

[pos]

Offline convolution looks like a good solution indeed.
SoX should be able to do that using the txt impulse format (never tried though).

What are you loudspeakers and correction settings?
What improvements are you hearing (halucinating? ) ?

[jmbee]

Originally Posted by pos

Hi jmbee

Yes, your tutorial is more in line with what Rvrazvan seems to be looking for!
Especially the second part, "Test avec filtre iir standard L-R. trois voies", as the first part is dealing with a system that is already quite linear in phase (using a modified DCX2496 for substractive filtering)

By the way, when using the foobar convolver plugin, it is best to uncheck the "Auto level adjust" checkbox.

Hi Pos,

Thank you for the advice, i have corrected.
Even with the DCX in subtractive-delay, Rephase alows to improve low frequency response, less boominess, more focused.

crd

[ra7]

Originally Posted by pos

Offline convolution looks like a good solution indeed.
SoX should be able to do that using the txt impulse format (never tried though).

What are you loudspeakers and correction settings?
What improvements are you hearing (halucinating? ) ?

It's a simple two-way with vented Deltalite2515 and SEOS12. I have large tractrix horns, but they are down for repair at the moment.

I corrected the vented response and the 6th order crossover at about 1200 Hz.

On one particular song, there is percussion with flute. With corrected phase, I seem to latch on to the flute, and everything makes sense. Without corrected phase, I latch on to the bass and the music doesn't make as much sense.

Instruments have more power in space, i.e., better defined, easily localized and I can follow them more easily. In general, it feels more relaxed as I can follow things more easily.

[pos]

Have you tired correcting only the bassreflex, and only the 1200Hz cross, to see where the differences come from?