A guide how to do room correction and use it in Roon


(Magnus) #181

You should zoom in so you get 20 - 20khz range and maybe 40 to 100 dB, It will make it easier to see.


(Daniel Beyer) #182

4 posts were split to a new topic: Audio DSP and Cabin Correction


(Thomas Fein) #183

Nice guide thanks.

I change on Mac constantly between Audirvana and Roon. Audirvana can include au-plugins, Roon does not.
The convolution method in Roon can in no case keep up with a room EQ of mathaudio. The sound quality is simply a class better.
I now have some experience with REW … only the achievable results even with this guide here, are not comparable to a plugin solution like RoomEQ.

To Roon staff: why not implement au / vst plugins?

If in a configuration the Au / vst interface does not work in Roon, e.g. for streaming solutions, the convolution method can still be used. Where is the problem?
For those who operate the Roon but simply PC or Mac supported, give us the Au / vst interface.

If the interface does not come I get out. First and foremost is the sound quality. And since Audirvana simply over the plugin interface sounds better.

The path over aulab / soundflower on the Mac is unfortunately too susceptible to interference.


(Mr Fix It ) #184

@moderators maybe the above post can be moved to a new feature thread?


(Geoff Coupe) #185

The suggestion of implementing au/vst plugins has been made before. This reply from brian is relevant:


(Steve) #186

But later Brian had a brainwave about it… it seems no problem or barrier is too great for his genius. :slight_smile: (not that it means we’re getting it, but I’m certainly more optimistic - at least for the distant future).


(Magnus) #187

[quote=“Thomas_Fein, post:183, topic:23800, full:true”]
The convolution method in Roon can in no case keep up with a room EQ of mathaudio. The sound quality is simply a class better.
[/quote]If that is the case, then a better solution would be to fix the EQ/convolution feature so its the same quality as mathaudio, would it not?

I have no experience with mathaudio, but I did compare this REW solution to Dirac, and the sound quality was to close to make and judgement what was best (at least for me and my equipment).


(Steve) #188

Never tried math audio, but I dare say the primary aspect affecting SQ in the Roon setup is how the filters are created. I’m happy with the REW result from the procedures outlined here but from memory Dirac was better. That said REW is free and Dirac isn’t. Also this REW technique deals with frequency/amplitude only (at least the main steps).

Those that have tried more advanced filter creation tools like Acourate swear by the results with Roon.

So I’m not saying Roons convolution is the best there is as there’s no way I could verify that, but it does seem people with high standards can get very good results from it. But something like Acourate involves a spend and some time investment.

Did you have any specific issues with the process here or it’s just the resulting sound you’re not happy with? What are the differences you’re hearing between Roon and Mathaudio. Maybe it would be worth posting your REW measurements?

The only other pointers I can think of is the target curve - perhaps the REW and mathaudio ones are dissimilar? I’ve been playing with targets since setting this up, and am only now just zoning in on a favourite. Really quite small adjustments - particularly bass - can have quite an impact on both short term and longer term enjoyment of the result and there’s quite a balancing act between what I want, and how my speakers/room react to it. At least in my setup anyway.

Without Dirac or Roons convolution from REW I just can’t turn my hifi up loud. It’s too boomy/muddy in the bass, and the treble far too aggressive. In fact it could well have caused an increase in tinnitus. With the REW/Roon room correction, I can rock out! Well, I could if I didn’t now have a baby! But when I get the window it goes loud and I smile. Good enough for me for now although one day I’ll try Acourate.

@AndersVinberg’s Acourate topic is here if you’re interested. He may be able to offer other opinions/advice as I believe he started out with REW.


(Magnus) #189

I recently bought a pair of B&W P7 Wireless headphones, and like them a lot. They have a very warm and pleasant sound. Naturally I wanted something similar from my speaker, so I experimented with house curves and found something I like.

A house curve like this is also something to try if you feel like the room correction guide gives a little to flat and “boring” sound. For example, if the room correction reduces your sound in the 100 hz area, acoustic guitars will sound less warm and more clinical.

Remember to set LF and HF slopes to zero at step 11 so you generate a pure flat response, and then you can apply the house curve like below in Roon.

This is probably not for the audio-purists though :slight_smile:


#190

I’m new to Roon but have experimented with room correction before using a DSpeaker Anti-Mode 2.0, REW and various home cinema systems (e.g. Audyssey). With each of those systems you place your microphone on a stand, run a sweep and take several measurements. The software then averages it all out.

My question about using “Pink PN” and moving the mic is this: don’t you run the risk of the mic picking up the sound of you moving around? For example, if you don’t move smoothly enough or your grip on the mic changes, the mic will pick this up surely?


(Mr Fix It ) #191

When running sweeps you should be out of the room…run the sweep via a remote terminal/screen/vnc session if you can

ie place the mic in the spot…get out of the room and measure…and repeat for each measurement position.


#192

Thanks wizardofoz, but I was wondering about the “moving mic” technique that Magnus describes at the top of this thread.


(Mr Fix It ) #193

I stand by the fact that you should not be in the room…unless perhaps you have a mic placed in your ear (like the Smyth Research guys do) … see the video here https://ksr-video.imgix.net/projects/2525427/video-690844-h264_high.mp4 buts this an entirely different means to an end but the principals are still there.

I have one of these coming…I’ve done the demo and and demo’d the unit to others…its insanely mind blowing. If there is a CANJAM or other show on nearby go check it out if they are participating.

But I digress … I guess you could sit in the listening position and have the mic on a stand and be very quiet…but Ideally most procedures suggest being out of the room or at least far away from the mic.

Also turn of other sources of noise like fans and A/C etc. Close windows and try to do it when there as little external noise interference as possible like passing traffic or construction work :smiley:


(Magnus) #194

There is typically a noise floor of 40+ dB, and in that case whatever sound you do (breathing etc) will not make a lot of difference. Also, you are present when listening normally, and your body influence how the sound reacts in the room, so from that perspective you should sit in your listening position when doing measurements.

I would guess its different when doing very precise measurement in quite rooms like a studio, maybe for phase adjusting speakers etc. But for normal room correction in a home environment, I would say its better if you are at the listening position than outside the room.

Using the moving-mic with Pink PN sound makes the reading more reliable, since it automatically averages the measurement over an area. But if you rather do 8+ sweeps for each channel and average them out in REW that also works (but will take longer time). My suggestion then would be to use the positions Dirac uses (see picture):

Measure for each channel for spot 2-9, and one measurement for both channels on position 1. Then average them for each channel (+ spot 1) in REW and perform equalization.


(Mr Fix It ) #195

I agree that having your body in the listening position is probably going to be the most accurate, but most programs, Dirac included don’t suggest as the fist measurement for Dirac would npmean the mic would be in your body/head.

Most guides will also say you should be out of the way, if not out of the room.


(Steve) #196

Out of the room is pretty impractical.

When I last measured, I put myself well back behind the mic with mic on an arm, and took measurements with me in several different positions to see what the effect was - it was negligible - they were all essentially the same.

I know some systems say to remove key furniture that’s in the listening area. Personally I ignore this since they’re there when I listen. Ok they may move slightly, but why correct for theoretical Room when you have the exact one at your disoosal. A dummy (or volunteer) at the listening seat could be a good idea, but I’ve never gone that far, and I remove myself because I measure over a wide area - I like listening generally in the room, including standing up.


(Magnus) #197

I think it also depends on what kind of room correction you want to perform. For example, if you measure a big couch in a living room, and want room correction to cover a wide area, then its probably best to stay out of the way (or at least behind the mic). But for a specific listening position, I think you should be at the listening position.

But it also depends on how you measure. I use the moving mic, 2 spirals in opposite directions outside each ear, and one spiral in front of my face, which is much easier to perform with some accuracy if you sit at your listening position.

I tried the Dirac measurements earlier, and by using the 90 degree microphone correction it was easy (and convenient) to do that when sitting at your listening position. The central one I did by leaning the head back a little and measure at the nose tip. The result was to close to tell apart from the moving mic method, but took much longer to perform in REW (a total of 17 sweep measurements vs 2 60 seconds measurements).


(Rémi) #198

Just discovered this thread, fantastic tutorial, an easy and efficient way to perform room/speakers correction in the frequency domain. If there is a Roon Award contest, @magnus you have my vote!

There is no doubt that the spatial averaging technique of the moving mike technique across your preferred listening area allows for a very efficient correction of the speakers and room in amplitude, at least as good as Dirac & Co.

Amplitude correction is the indisputable STEP 1 that any “dematerialised” audiophile has to implement. The cost is ridiculous against the benefits. Consider it before buying any cable of any kind above 100$ (price of the microphone). STEP 0 is of course to ensure proper placement of the speakers and listener, as well as room treatment is feasible.

My experience is that the audio message and soudstage can be further improved with additional corrections/convolutions, that can come on top of the amplitude correction (Roon allows to chain convolutions so you can pile up as many as your processing power allows).

  • STEP 2 : correction of the phase curve and time alignement of speakers : the impact goes from “no change” to “wow” depending on your speakers and personal sensitivity. I recommend to try it if you listen a lot of acoustic recordings, percussions, guitars… The dynamic and clarity should improve. Dirac/Acourate/HAF/Audiolense do it pretty well with a cost (evaluation is free though). You can implement it for free using REW in combination with Rephase but it requires some time and is a bit more technical than the RTA/MMM amplitude correction presented by Magnus.

  • STEP 3: further help your brain to feel you’re with the musicians
    Hifi is about creating an illusion of you being with the musicians playing in a studio, a concert hall, a jazz club… Frequency balancing of the reverberant sound corrects the unnatural tone of the reverberation caused by the directivity pattern of your speakers and the specifics of your room (for example if you have an irregular reverberation time over the spectrum, check the RT60 screen in REW under “Overlays”). The brain doesn’t like it because it’s not natural of a studio/concert hall/jazz club. I have implemented this correction in my (difficult) room and got a terrific improvement in the soundstage despite the absence of any room treatment. The walls have disappeared, the soundstage is super-wide (goes well beyond the walls !).
    X-talk reduction is in my view is a must if you listen a lot of acoustic “live” recordings made with dummy heads or standard stereo recordings (two microphones, one for “left ear”, one for “right ear”). These recordings are fine when listened to via headphones. But when listened with speakers, what comes from the left speakers goes to your left ear AND right ear, same for right speaker ! This is the X-talk. Quite strangely it is not proposed in standard by DSPs even though it is not that difficult to implement.

In my case going through STEP 3 provided a lot of benefits on most of my records, with no negatives. I went through HAFservice and they took care of STEP 1/2/3. (NB: I am not affiliated to HAF in any way, and paid for the service, actually 3 times cheaper than Dirac). It would be good if bigger players like Dirac could provide such advanced features ! We discuss it here and also here.

EDIT: tor those interested here is my view on the current market offering for room/correction/convolution. One could add a column for the REW/MMM/RTA approach documented in this thread : Amplitude correction only (the most important thing to do anyway), quite easy to apprehend and implement, and completely free, except for the cost the microphone of course.


(Steve) #199

I love that statement. Time and time again I see people discussing spending sometimes thousands on speaker cables, interconnects, digital cables, and power cables, yet have no idea what/how these cables intend to improve. Placebo aside, it could well just be a case that any particular cable has a frequency reduction/increase right where you need it, and is why they sound ‘better’ rather than due to any expensive magic. Of course the trial and error to find the right combination is probably worse than needle in a haystack.

Hey, I’ve been there (haven’t we all?) - maybe not thousands of pounds but I’ve spent money chasing cable and ‘decrapifier’ improvements that would be completely insignificant to Room Correction - I was literally blown away when I discovered Dirac.

I know room design/treatment is the best and also simplifies things (it just works with whatever you put in there) but for so many of us it’s just not an option. Those who are in this position but ignore DRC because it ‘takes the life out of the sound’ or whatever criticisms you hear - really should try a modern implementation. I can only assume all the bad press is from poor implementations, maybe old ones using early technology/maths.

I ignored many times when more knowledgeable people said ‘measure your room’. I paid a hefty price with kit changes that were never going to fix the problem. Now I say it to everyone! Measure!!

And after that the biggest difference has been speaker isolation (isoacoustic gaia footers to be precise), which has been similarly transformational for my suspended floor setup and the second best money I’ve ever spent (or will spend, they’re on loan). :slight_smile:


(John B) #200

Most likely a silly question but did you have to change your DSP settings because the gaia footers raised the speaker somewhat?

.sjb