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REW Help - how to measure with EQ applied?

QMuse

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My setup is win10 laptop running Roon and REW connected to ADI-2 DAC, which feeds two NC400 amps.

What would be a good way to check the results of the REW filters?

REW can generate filters in wav format and IIRC there is a way to load them in Roon. You should also take care to apply fitler attenaution in Roon equal to max filter gain which is specified on upper right corner of REW's EQ window. Attenuation wouldl probably differ for left and right channel fitlter so in Roon you should use larger of them for both channels.
 

QMuse

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REW can generate filters in wav format and IIRC there is a way to load them in Roon. You should also take care to apply fitler attenaution in Roon equal to max filter gain which is specified on upper right corner of REW's EQ window. Attenuation wouldl probably differ for left and right channel fitlter so in Roon you should use larger of them for both channels.

Here is a step-by-step guide how to do it with Roon.
 
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airs

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Here is a step-by-step guide how to do it with Roon.

Thanks Qmuse! I found a program called Voicemeeter which effectively allows Roon and EQ APO to work in tandem. I’m not certain I’m doing it correctly yet but so far it looks like this:

1. Measure and create filters in REW
2. Export filters as text
3. Load filters into EQ APO, adjust gain (using additional preamp control), and channels as needed
4. Repeat steps 1-3 until satisfied
5. Set Voicemeeter to use your DAC in exclusive mode
6. Set Roon to output using the Voicemeeter device.
7. Change settings and filters on/off in EQ APO for instant effect on your music playing in Roon.

Anyone else have experience with this type of chain? Hopefully I’m not butchering things!
 
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QMuse

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Thanks Qmuse! I found a program called Voicemeeter which effectively allows Roon and EQ APO to work in tandem. I’m not certain I’m doing it correctly yet but so far it looks like this:

1. Measure and create filters in REW
2. Export filters as text
3. Load filters into EQ APO and adjust gain and channels as needed using additional preamp control.
4. Re-measure with REW and create more filters if necessary, import them into EQ APO, etc.
5. When satisfied, set Voicemeeter to use your DAC in exclusive mode
6. Set Roon to output using the Voicemeeter device.
7. Change settings and filters on/off in EQ APO for instant effect on your music playing in Roon.

Anyone else have experience with this type of chain? Hopefully I’m not butchering things!

I haven't tried it but I would certainly avoid adding EQ APO in the chain when Roon can do it without it.
 
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airs

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I haven't tried it but I would certainly avoid adding EQ APO in the chain when Roon can do it without it.

Is there a detriment to using EQ APO in the chain? I find it easy to use and more feature rich than Roon's EQ options. It also updates the sound instantly - there's no pause in the music like you get when you make a change in Roon.
 

Daverz

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REW can generate filters in wav format and IIRC there is a way to load them in Roon. You should also take care to apply fitler attenaution in Roon equal to max filter gain which is specified on upper right corner of REW's EQ window. Attenuation wouldl probably differ for left and right channel fitlter so in Roon you should use larger of them for both channels.

Do you mean the "headroom reqd" number?
 

QMuse

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Is there a detriment to using EQ APO in the chain? I find it easy to use and more feature rich than Roon's EQ options. It also updates the sound instantly - there's no pause in the music like you get when you make a change in Roon.

I think EQ APO bypasses ASIO and goes via Windows audio stack, which I would avoid if possible, and in this case it's certainly possible. You will be using Roon's convolution engine to run filters you designed with REW so you shouldn't be interested in any "EQ features" some other tool offers.

There is also a general recommendation to avoid unnecessary chains in audio link.
 
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Matias

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I use Equalizer APO to apply the curves. and then i measure again for verification
This. As demonstrated here in this excellent video.

 
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airs

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I think EQ APO bypasses ASIO and goes via Windows audio stack, which I would avoid if possible, and in this case it's certainly possible. You will be using Roon's convolution engine to run filters you designed with REW so you shouldn't be interested in any "EQ features" some other tool offers.

There is also a general recommendation to avoid unnecessary chains in audio link.

Thanks QMuse, I will look into this. Currently I have EQ APO operating on the Voicemeeter Virtual WASAPI device's output, which is mapped to my ADI-2 DAC ASIO. Roon is configured to use the Voicemeeter Virtual WASAPI device as well. The Roon chain displays it as "lossless" but perhaps it doesn't have the ability to look into the details of the link.

To switch the EQ over to Roon's Convolution engine, I need to create the filters as WAV files and zip them up. What I don't yet understand is how to duplicate what I've done in EQ APO in REW filters. That is,

1. Apply a specific filter to a specific channel
2. Apply a gain to a specific filter
 
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QMuse

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Thanks QMuse, I will look into this. Currently I have EQ APO operating on the Voicemeeter Virtual WASAPI device's output, which is mapped to my ADI-2 DAC WASAPI. Roon is configured to use the Voicemeeter Virtual WASAPI device as well. The Roon chain displays it as "lossless" but perhaps it doesn't have the ability to look into the details of the link.

To switch the EQ over to Roon's Convolution engine, I need to create the filters as WAV files and zip them up. What I don't yet understand is how to duplicate what I've done in EQ APO in REW filters. That is,

1. Apply a specific filter to a specific channel
2. Apply a gain to a specific filter

I think Roon requires a single wav stereo filter which would contain filter for both channels in a single file.

You don't apply gain to a filter as it is already there - you have to apply attenaution in convolution engine to compensate (annulate) for that gain in order to avoid clipping.
 
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airs

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I think Roon requires a single wav stereo filter which would contain filter for both channels in a single file.

You don't apply gain to a filter as it is already there - you have to apply attenaution in convolution engine to compensate (annulate) for that gain in order to avoid clipping.

Roon asks for either a single WAV file, or a ZIP file containing multiple WAV's.

With respect to gain and channels, in EQ APO I apply gain on a per filter basis. The same is done for channel assignment - its per filter. How is this accomplished in REW filters which get exported to WAV for import to Roon?
 
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I found the answer to how to apply filters to individual channels in Roon - you can use the Procedural Equalizer to choose which channels to apply EQ to. I have not yet found a way to apply gain to individual channels/filters, though. Perhaps this would be done with a broad filter from 20-20000?
 

Soniclife

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I found the answer to how to apply filters to individual channels in Roon - you can use the Procedural Equalizer to choose which channels to apply EQ to. I have not yet found a way to apply gain to individual channels/filters, though. Perhaps this would be done with a broad filter from 20-20000?
In roon you can add the 'parametric EQ' into the playback chain, and then configure each filter individually.
https://kb.roonlabs.com/DSP_Engine:_Parametric_Equalizer
This is a great way to explore the impact of each filter, as you can turn them on and off during playback.

I prefer to export the filters as wav from REW, zip them and import into roon in the convolution filter.
https://kb.roonlabs.com/DSP_Engine:_Convolution
In REW do File > Export > Export Filter Impulse as WAV.
Select stereo, you correct left and right measurments that have the filters in them, and select all the sample rates at the bottom. Same them, zip them and import as detailed above.

For measuring the filters export the test signal from REW into roon, and play it as any other file. Pink noise and RTA method works well for this.
https://www.audiosciencereview.com/forum/index.php?threads/rew-moving-microphone-method-help.12641/
 

o2so

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In roon you can add the 'parametric EQ' into the playback chain, and then configure each filter individually.
https://kb.roonlabs.com/DSP_Engine:_Parametric_Equalizer
This is a great way to explore the impact of each filter, as you can turn them on and off during playback.

I prefer to export the filters as wav from REW, zip them and import into roon in the convolution filter.
https://kb.roonlabs.com/DSP_Engine:_Convolution
In REW do File > Export > Export Filter Impulse as WAV.
Select stereo, you correct left and right measurments that have the filters in them, and select all the sample rates at the bottom. Same them, zip them and import as detailed above.

For measuring the filters export the test signal from REW into roon, and play it as any other file. Pink noise and RTA method works well for this.
https://www.audiosciencereview.com/forum/index.php?threads/rew-moving-microphone-method-help.12641/

Long shot but how do you export the test signal from REW to Roon?
 

YSC

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I got a strange question, done the Equalizer APO to my holoaudio Spring 2 dac, but after applying the EQ and re measure in REW it basically didn't change at all... any idea why that may be? the driver should be using Java in REW as default
 

BrokenEnglishGuy

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Oh I see



So you cannot re-measure the result and see it from REW - APO EQ.... I thinked i was doing something wrong because is very wtf.


Why you cannot see the results? its very dumb.
 

YSC

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Oh I see



So you cannot re-measure the result and see it from REW - APO EQ.... I thinked i was doing something wrong because is very wtf.


Why you cannot see the results? its very dumb.
lol that's a long time back, since then I found it's the windows 11 setting blocking the APO from being effective, now it's up and running amazingly
 
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