Equalizer APO, REW and Rephase WOW!

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I've been working on calibrating audio systems for so long and now this combination is truly something special to me.

I would like to offer help to anyone who would like to learn how to make use of these tools because all of them are free and they can replace a lot of very expensive hardware.

Here's a great example of that.

Using Equalizer APO, you can copy the L and R channel to other outputs on an 8 channel sound card. Then you can use REW to dial in the exact FR that you want and save those filter settings to a file. Then open rephase, import the measurement from REW and the filter settings. In rephase you can also correct the phase and set up crossovers for each channel. Save the impulse as a mono WAV and select that as the convolution filter in Equalizer APO and WHAM you've got an active crossover, linear phase system.

You can then remeasure that channel, create another filter to fine tune the response and load that into the next bank in rephase to make a more refined impulse file. You can repeat that enough times to make your frequency response look unbelievably smooth.

This system is superior to a lot of pro tools like Diraclive because for one thing, dirac live is practically useless for phase correction because you can only get accurate phase data at close range with lower volume levels. Rephase allows you to correct phase blind by inputting the crossover topology.

One of the best things about Equalizer APO's convolver is that it's suprisingly low latency.

I'm starting this thread to see what kinds of projects you all have going on using any of these amazing tools.
 
Yes it's a great solution.

But it's not perfect. I miss a system wide solution in the sense that some programs will think your sound output is configured for 7.1 and not stereo. Then you have to chose stereo sound in each program, for instance in Netflix you have to set this for each new episode or movie you want to watch. Some programs or games cause serious head scratching before you figure out how and where to change this.
 
Do you know how to time-align channels after i set a impulse response in APO for only 2 outputs of the 6 i use?
Is there a setting that i can tell EqAPO to start play all channels at the same time AFTER it did all calculations?

Thank you!

Yes, this can be a major issue. One of the things that I like to do in this situation is to export the REW filter settings as text and in EQAPO at the control/include and select that text. That will apply the EQ with no latency for those channels. If you use the convolver it will screw with latency quite a lot. I often use the convolver to correct phase only so that I can use the same impulse for each channel. In this way I'm mainly phase correcting the crossover and not so much going for ultimate phase linearity.

It seams that if you run the convolver on every channel EQAPO is smart enough to line things up pretty well, but using the convolver on just 2 channels has problems.
 
Yes it's a great solution.

But it's not perfect. I miss a system wide solution in the sense that some programs will think your sound output is configured for 7.1 and not stereo. Then you have to chose stereo sound in each program, for instance in Netflix you have to set this for each new episode or movie you want to watch. Some programs or games cause serious head scratching before you figure out how and where to change this.

Yes, I haven't been able to solve that problem. Does anyone know how to copy a channel to another device? That would help get around this issue. Then you could let the default sound card be in stereo but copy the channels to another sound card that is running in 7.1 for some fancy crossover tricks or even use 7.1 as default and copy to several other 7.1 devices for a really elaborate crossover setup. I'm hoping we can help each other solve some of these issues.
 
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CabinetMakerRyan:

Currently not supported by eqapo. Must be the same device.
Pondering if it's possible to re-route the audio by other means, have not seen any obvious path yet.

If device is set to "not default" for windows, audio will not be routed. Cannot link with device such as virtual audio cable, cannot link with actual audio cable, cannot copy sound from one device to another. I'm stuck.

Also mentioned this somewhere else, but it may seem that setting gain in config affects q of filter somehow. It sounds very different if you change gain in rephase as opposed to setting gain in config.

... Currently considering moving to Linux due to more customizeable audio path. Do not completely understand what's going on but sometimes I notice lag on audio/picture, other times it seems fine. My filters are 22ms, do not think the filters themselves are the problem, maybe the audio path in Windows varies somehow depending on program.
 
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...
Ok, so after much desperation I finally managed to find a program called Pedalboard 2, it works, it's simple enough for even me to figure out, and after configuring it I just set it to automatic startup procedure with admin rights, seems to work fine. It seems to automagicly do the job even after reboot, which is awesome. CPU usage is not worth mentioning at all, between 0 and 0,5%.

A bit concerned about lag, it's definitely different from before, not sure if it's for the better or worse yet, but seems more stable at least.

niallmoody.com - Pedalboard2

It may well be that there are other programs more suited for the job, but this worked for me, at least in my quest for linking different devices together, I pray to the deity of digital sound processing that this will be sufficient. Should there be too much lag still I can probably get it down to around 10ms for filters with a bit more work, but it seems fine for the short time I've tested it.
 
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Sorry about the bumping.

Just want to point out that one of the main advantages of Pedalboard 2 is that you can route the stereo channels to whichever output you want on your designated soundcard.

So I tried to cut away the pre-mix of eqapo just to test it, and went for 10,667ms filters, now there is exactly the same amount of lag on my monitor as my audio signal path, when watching the audio output of the hdmi cable compared to the audio cable there is no delay when watching the default output of windows, but the lag of the (actual) hdmi output is visible on screen, and also the oscilloscope of foobar there is no lag between audio and video.

Win!
 

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I've been working on calibrating audio systems for so long and now this combination is truly something special to me.

I would like to offer help to anyone who would like to learn how to make use of these tools because all of them are free and they can replace a lot of very expensive hardware.

Here's a great example of that.

Using Equalizer APO, you can copy the L and R channel to other outputs on an 8 channel sound card. Then you can use REW to dial in the exact FR that you want and save those filter settings to a file. Then open rephase, import the measurement from REW and the filter settings. In rephase you can also correct the phase and set up crossovers for each channel. Save the impulse as a mono WAV and select that as the convolution filter in Equalizer APO and WHAM you've got an active crossover, linear phase system.

You can then remeasure that channel, create another filter to fine tune the response and load that into the next bank in rephase to make a more refined impulse file. You can repeat that enough times to make your frequency response look unbelievably smooth.

This system is superior to a lot of pro tools like Diraclive because for one thing, dirac live is practically useless for phase correction because you can only get accurate phase data at close range with lower volume levels. Rephase allows you to correct phase blind by inputting the crossover topology.

One of the best things about Equalizer APO's convolver is that it's suprisingly low latency.

I'm starting this thread to see what kinds of projects you all have going on using any of these amazing tools.

Are these links ok for free download?

https://sourceforge.net/projects/equalizerapo/

https://sourceforge.net/projects/rephase/

REW - Room EQ Wizard Room Acoustics Software
 
...
Ok, so after much desperation I finally managed to find a program called Pedalboard 2, it works, it's simple enough for even me to figure out, and after configuring it I just set it to automatic startup procedure with admin rights, seems to work fine. It seems to automagicly do the job even after reboot, which is awesome. CPU usage is not worth mentioning at all, between 0 and 0,5%.

A bit concerned about lag, it's definitely different from before, not sure if it's for the better or worse yet, but seems more stable at least.

niallmoody.com - Pedalboard2

It may well be that there are other programs more suited for the job, but this worked for me, at least in my quest for linking different devices together, I pray to the deity of digital sound processing that this will be sufficient. Should there be too much lag still I can probably get it down to around 10ms for filters with a bit more work, but it seems fine for the short time I've tested it.

Thanks! I'm going to check this out, this looks like it has a lot of potential.
 
Thanks! I'm going to check this out, this looks like it has a lot of potential.

I thought so to, until I discovered that it stops working when the screen saver kicks in so it needs a restart, probably not a problem for non hdmi outputs.
Also does not seem to work with other VST plugins than the default selection.

Still looking around.
 
I've been working on calibrating audio systems for so long and now this combination is truly something special to me.

I would like to offer help to anyone who would like to learn how to make use of these tools because all of them are free and they can replace a lot of very expensive hardware.

Here's a great example of that.

Using Equalizer APO, you can copy the L and R channel to other outputs on an 8 channel sound card. Then you can use REW to dial in the exact FR that you want and save those filter settings to a file. Then open rephase, import the measurement from REW and the filter settings. In rephase you can also correct the phase and set up crossovers for each channel. Save the impulse as a mono WAV and select that as the convolution filter in Equalizer APO and WHAM you've got an active crossover, linear phase system.

You can then remeasure that channel, create another filter to fine tune the response and load that into the next bank in rephase to make a more refined impulse file. You can repeat that enough times to make your frequency response look unbelievably smooth.

This system is superior to a lot of pro tools like Diraclive because for one thing, dirac live is practically useless for phase correction because you can only get accurate phase data at close range with lower volume levels. Rephase allows you to correct phase blind by inputting the crossover topology.

One of the best things about Equalizer APO's convolver is that it's suprisingly low latency.

I'm starting this thread to see what kinds of projects you all have going on using any of these amazing tools.

Hey! so i've been a lurker here for some time, and too have found sanctuary in REW/EAPO but have had minimal success pulling off convolution successfully. I have a rather unique setup compared to most

GEAR
htpc: win7, plex for 90% of stuff watched. EAPO with a miniDSP UDAC8 which is a usb DAC converter giving me 8 RCA outputs at 2vRMS

denon 2310: has multi-in, use to power LCR (diysg fusion8) and SUR L+R (volt 6s)

diy icepower amp: have 3 magnum12 woofers in a custom 2.5cuFt tuned to 24hz that are powered off this

CURRENT SETUP

EAPO pushes all channels to virtual channels for processing (split.txt)

LR4 for a 250hz split between LCR highs (fusion8) and LCR lows (magnum12s) (crossover.txt) https://sourceforge.net/p/equalizerapo/discussion/general/thread/6630d140/

subsonic LR4 17hz on the subs (subsonic.txt)

hp LR4 70hz on SUR (surcross.txt)

delays on each channel with some basic math as a starting point then using the generated sign wave at crossover freq to adjust in REW with RTA for highest output (delays.txt)

level match with pink noise to each channel independently, -20db signal, with -10 volume output calibrated to 72db on all channels (levels.txt)

eq <-- this is where i'd love to use the filters, but for now i took the LCR highs measured together, did an auto eq in REW and use a single filter for LCR highs. reason for this was when i did each speaker independently, the sound just lost all of it's dynamics. Sounded dull and soft. perhaps i did something wrong who knows

then the rest of the includes are essentially the channel mapping back to the outputs, and since i have no dedicated SUB channel, the SUB output is added to each of the LCR low channels at a -4dB*SUB+Low

That said, could you walk me through how i would achieve replacing my EQ section with a rePhase convolution filtering? i used DRC designer, but that wanted me to have impulse responses for LR in stereo. i'd like to have a convolution filter for each channel if possible. all 8 if doable
 
Just got to say I moved over to just using Pedalboard with Engineers filter from Robin Schmidt
RS-MET

Been toying especially with the Elliptical filters, ridiculously sharp filters. Currently trying out 16 order elliptic with 0,1db ripple. It's very effective, trying to find a downside other than a few % more cpu usage.
Extremely simple setup, just "connect the dots", set the filters to whatever you want and just press play. I've spent so much time chasing around for a good solution, and it's been hiding under my nose. Just have to use the 32bit version of Pedalboard, and then it's all good.
 

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The Pedalboard + VST plugins is a much faster way to test filters and setup than using EQ Apo, the EQ Apo is probably superior in sound quality, at least when combined with RePhase. But Pedalboard and the various filters from Robin Schmidt is just really good for switching between setups, can have an array of different EQ and filter setups, with very few mouseclicks (4) I can change between whole setups of filter settings to see which I prefer. Also added 1 "global" EQ, as well as 1 for each channel.

So far my personal preference seems to be a mix consisting of 96db/oct LR at 104hz 48db/oct LR at 337hz and 12db/oct Bessel at 1157hz in my setup, currently looking for the right VST phase correction tool. It really is quite nice to have some buttons to tweak, even though they are on a screen. Feels like a more "hands on" approach than using REW, RePhase and EQ Apo. I guess that's the sum of it, people are different and have different preferences.
 
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