Using REW to do Room Correction

Thats correct, best is if you generate one wav for each output frequency supported, then zip them and use the zip file from REW. If you do it like that, the EQ will not show anything and you don’t need to make any EQ adjustments.

Yes. REW can do two things - generate PEQs which can be manually fed into Roons PEQ, or export waves for the convolution. So it would usually be one or the other.

Of course, nothing then stops you making additional adjustments with PEQ on top of the convolution - say you wanted more bass, or just felt something needed tweaking and it was easier to do it that way rather than go back and regenerate convolution filters.

It might be interesting to set it up both ways (convolution vs PEQ) and see how the sound output compares.

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I have done the comparison between Roon PEQ and Roon convolution.
This is the setup: MacMini USB -> Mutec MC3+USB -> Chord 2Qute (optical SP/Dif), Roon volume leveling, sample rate conversion to 192 kHz. For the convolution I used two identical mono (L and R) 192kHz impulse waves with 131k taps generated by rePhase with the PEQ settings in Roon.

Two observations: Roon PEQ dulls the sound quite a bit while convolution does not, even without PEQ correction (PEQ and individual correction “on”, but all PEQ gains at 0 dB).
Also, convolution correction seems to work stronger than Roon PEQ. For instance, applying -1 dB gain on a frequency with convolution sounds to my ears more like -3 dB with Roon PEQ.

I am quite happy with convolution in Roon.

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If thats correct then the devs at Roon has some work to do. But you say you generate the wav files in rephase, but rephase does adjust the phase also. If you generate the wav from REW, and then apply the same REW EQ to Roon, and switch between those, is there still a difference (there should not be as far as I know).

I could not hear any difference switching on/off an “empty” EQ in Roon.

I used the wavs from rePhase without changing the phase. In rePhase the phase changes caused by the PEQ are visualized but you can choose not to compensate for that (it is a manual action), which is what I did for the Roon PEQ/convolution comparison. I hear minor differences when I compensate for phase changes, but I can not tell if it is better or worse. Just different to a very small extent.

I have to mention that the Mutec MC3+ removes a lot of the jitter “veil” and lowers the background noise a lot. Maybe that is why I am picking up these differences.

I wrote a complete guide about how to do room corretion in Roon, in a way that has given me the best result. Check it out: A guide how to do room correction and use it in Roon

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When copying the Dirac measurment into roon manually, how can I set different filters for each loudspeaker?
The Dirac measurment shows different curves for each loudspeaker and sets different filters for each one.
At least this is how I think Dirac works, because you can set the target curve for each one individually.

Unfortunately, you can’t. The PEQ settings in Roon apply to both left and right speakers. You can use the average dirac measurement (making sure both L & R channels are linked together) and use that as your guide.

In light of Roon linking the L and R speakers together, how would one use REW to generate PEQ filters for Roon for a surround environment with two subwoofers? Or is Roon sound correction solely for a two channel system? JCR

@Mirco_Strauss @Jeffrey_Robbins Away from my system at the moment, but i think you can use Procedural to set up over-channel PEQ.

I just took a look more deeply and @AndersVinberg is correct. You can add a procedural EQ filter and within that create Parametric EQ operations that apply to certain channels. Hadn’t seen that before.

You can also generate stereo .wav impulse files for use with the convolution engine in Roon.

I noticed most folks on this thread were exporting REW’s measurement sweep to Roon and playing that for measurement.

I exported REW’s pink noise generator and then used the real-time measurement in REW.

Is there any reason to prefer one over the other?

Thanks,
Jeff.

The advantage for me is the setup’s simpler to playback through Roon as the cabling’s already there and I stream over Ethernet. It means I don’t have to use separate USB from my laptop to the DAC - which would mean two long USB leads as I use along one for the mic too. It also means you are playing back through the usual chain which is what you need to do if you want to measure the effectiveness (i.e. With convolution enabled).

The disadvantage is it’s more fiddly to output only left or right. You either mute channels in a procedural EQ, or in your DAC/amp if its possible (and simple). Or as fallback you could pull out speaker cable - but I’m sure for most the procedural works.

I’m sure there will be other reasons.

Next time I may investigate making two more versions of the pink pN file - with L and R separately muted to make it quicker and less likely to forget a step.

By having the signal (whether sweep or pink noise) as a file you can play in Roon, you can measure after adding Roon’s DSP correction, and thereby verify which that it all worked as expected.

Wrt sweep vs. pink noise, the sweep fits in with most exact measurement techniques, real time measurement from pink noise is very easy.

Thanks, guys.

Just to be clear, I am always playing back through Roon (so that I can test the results of different PEQ settings).

The question was just whether to use a sweep or PN. I’ve been using PN, but I might try a sweep just to see if there’s any/much difference.

Checking in to see if anyone has yet got Roon and REW to work together for multichannel speaker correction. JCR

Hi all,

I am using the minidsp umik-1 micro together with REW.

A simple question:
There is a 90-degree and a 0-degree calibration file.

Please have a look at the (symbolic) photo: Is this the 90-degree or the 0-degree position? And: what position to prefer?

Thank you!
Christoph

Your photo shows a mic at 0 degrees.

Generally, 0 degrees is used for a stereo setup.
90 degrees, i.e. Vertical or pointing to the ceiling, is used for a surround setup.

I’m sure I tested both, some years ago now, and decided that in my room, any difference was insignificant. As I’m sure you’ll appreciate it is a simple test for you to perform and come to your own conclusions.

You may like to read this excellent topic guide-how-to-do-room-correction-and-use-it-in-roon

It suggests measurements can be performed with a moving mic rather than sticking to a static/fixed position.

Thank you Alan!