Dirac room correction when primary listening position is not centered

[digitalmallrat]

Quick question about using Dirac room correction. I see through the program has recommended locations for the microphone and seems to prioritize around the main listening position. My question is: our living room is oddly shaped and we have an L shaped couch where the main/optimal listening position would be on the tip of the L (see crude photo here). How exactly should I run the Dirac room correction? Just center it around the main listening position, or should I place the microphone also on the other parts of the couch?

 

[Tangband]

Quick question about using Dirac room correction. I see through the program has recommended locations for the microphone and seems to prioritize around the main listening position. My question is: our living room is oddly shaped and we have an L shaped couch where the main/optimal listening position would be on the tip of the L (see crude photo here). How exactly should I run the Dirac room correction? Just center it around the main listening position, or should I place the microphone also on the other parts of the couch?

With all room correction programs the results always gets better if you consentrate only on the main listening position.
If you do this ( a single microphone measurement ) you can sucessfully do eq up to about 200 Hz .

The cons with this is that the sound will be worse than before the calibration on every other place in the room.

But:

If you only correct for the fundamental room resonanses, meaning below 80 Hz in a normal room, the sound can be better on all listening positions. The fundamental room resonanses in a room is independent of the placement of the loudspeakers and listeningposition. A fundamental room resonanse is happening when sound bounces from a wall to the opposite wall many times. There are just 3 fundamental resonances you need to correct in a normal rectangular room, depending on the geometry of the room. Wall to wall , roof to floor, wall to wall.

There is a lot of misunderstanding or confusions about the differences between room resonanses and reflections.
One must learn about the differences and learn about wavelengts to be able to make good decisions.

You wont get any help from reading magazines regarding roomcorrection programs because most hifijournalists dont understand the difference between resonanses and reflections.

 

[abdo123]

For the first primary location it’s important to have it where a listener would sit in a stereo setup. So as close as possible to the center between the speakers.

As for the other measurement points, place it where other people would be actually sitting.

However, limit the correction only to 250Hz and Below. Full-range correction over very wide and irregular spaces is a bad idea.

 

[RayDunzl]

I'd correct for the tip of the couch, assuming you might be doing some "critical listening" there, and see if the sound elsewhere is "good enough" for those locations.

If you don't listen critically in the sweet spot, do da best you can with what you got to work with, until you reach a state of satisfaction (or not), then lay back and watch a movie.

If you can save more than one "correction", try different locations.

 

[JP78]

@Tangband
So if I get your answer right. If I have a room that doesn't allow me to have the sitting position in front of the speakers, I make a straight measurement in front of the wall straight in front of the speaker. According to what you say, it will then correct it for this position, and as this measurement is well, distribute the waves better throughout the room - hence one position corrected, better distribution?

I have a 25x9m Room - stairway and straight large wall in front of the speaker - left corner kitchen, right corner large living room area with dinner table and sofa area.
So far, it's not too bad, as the speaker is going straight to a wall in the middel of the room (no sitting area in front) and comes back straight to a wall. I have a streamer that would allow for Dirac life correction.

So, you would recommend to just take the measurement as when my sweat spot for listening would be in front of the speakers - do I get your advice right?

 

[Tangband]

@Tangband
So if I get your answer right. If I have a room that doesn't allow me to have the sitting position in front of the speakers, I make a straight measurement in front of the wall straight in front of the speaker. According to what you say, it will then correct it for this position, and as this measurement is well, distribute the waves better throughout the room - hence one position corrected, better distribution?

I have a 25x9m Room - stairway and straight large wall in front of the speaker - left corner kitchen, right corner large living room area with dinner table and sofa area.
So far, it's not too bad, as the speaker is going straight to a wall in the middel of the room (no sitting area in front) and comes back straight to a wall. I have a streamer that would allow for Dirac life correction.

So, you would recommend to just take the measurement as when my sweat spot for listening would be in front of the speakers - do I get your advice right?

I will give you a short answer to your question: If your room doesnt allow you to sit in the sweet spot in front of the speakers, then the stereosound will be very bad and any room correction is a waste of both time and money. Get your loudspeakers and listeningposition perfect first, then start fiddling with correction programes.

If WAF is the problem, or the room estetics, you can forget having a good sound.
You seems to have a big room ( which is good for sound ) so Im sure you can find a solution.

 

[Axo1989]

With all room correction programs the results always gets better if you consentrate only on the main listening position.
If you do this ( a single microphone measurement ) you can sucessfully do eq up to about 200 Hz .

The cons with this is that the sound will be worse than before the calibration on every other place in the room.

But:

If you only correct for the fundamental room resonanses, meaning below 80 Hz in a normal room, the sound can be better on all listening positions. The fundamental room resonanses in a room is independent of the placement of the loudspeakers and listeningposition. A fundamental room resonanse is happening when sound bounces from a wall to the opposite wall many times. There are just 3 fundamental resonances you need to correct in a normal rectangular room, depending on the geometry of the room. Wall to wall , roof to floor, wall to wall.

There is a lot of misunderstanding or confusions about the differences between room resonanses and reflections.
One must learn about the differences and learn about wavelengts to be able to make good decisions.

You wont get any help from reading magazines regarding roomcorrection programs because most hifijournalists dont understand the difference between resonanses and reflections.

I don't agree with this really, but it may be just the semantics of 'fundamental'.

If you model or measure a small-medium room there are numerous room modes: axial, tangential and oblique. Starting from lowest frequencies you will see multiples of your lowest modes, for all directions. In a typical room, combinations of these might reduce energy at LP from the mid-bass through to the lower midrange, for example.

Position of the speakers will make a definite difference to the interplay of peaks and nulls at LP, and position of LP in the room will do the same.

You can certainly limit correction to just the sub-bass and bass frequencies if you like. And you can correct for a small LP sweet spot. But I don't do either of those, for me using Sonarworks with multiple measurements (~40 iirc) around LP gives beneficial correction cross the audible frequency range. I use the B&K '74 curve to give a gentle downward slope to FR as my room isn't heavily furnished. Dirac gives you all sorts of options for measurement numbers and target curves etc. Sonarworks will correct FR and timing for a slightly off-centre LP, I'd assume Dirac has an equivalent. But we assume a basic stereo triangle as you say in your next post, I completely agree there.

What you can't do with DSP really though is fix your room's reverb time (but this may be mitigated somewhat as a side effect of reducing certain peaks).

 

[Tangband]

A thick rug in front of the listeningposition on the floor between the speakers , as big as the L and R speaker distance or more, can bring down the rooms reverb level significantly. A wooden or concrete floor without a rug will sound terrible. This is the first acoustic fix to do, before others and before using any DSP roomcorrection. Then, your speaker needs to be set up correctly in the room so you can hear the base tunes in the clearest way. This must be done by listening to real music.

Further, ( in my opinion ) 2 channel playback needs some reflections from the sidewalls to fill up the flaws in the stereo system - utimately about 20 ms delayed reflections , meaning you need a big listeningroom.

 

[Axo1989]

A thick rug in front of the listeningposition on the floor between the speakers , as big as the L and R speaker distance or more, can bring down the rooms reverb level significantly. A wooden or concrete floor without a rug will sound terrible. This is the first acoustic fix to do, before others and before using any DSP roomcorrection. Then, your speaker needs to be set up correctly in the room so you can hear the base tunes in the clearest way. This must be done by listening to real music.

Yes for sure, but minimal/ad hoc treatments (like a rug, or furniture) have their limitations. Incidentally Darko's latest video shows his experience just now moving to a house in Portugal: the architecture is all hard surfaces and reverb so his rug and sofa aren't doing it. His otherwise untreated RT60 as around a second across the range. Shite. Waiting for a visit from his acousticians obviously.

I don't have a reverb issue personally: Japanese architecture is pretty much the opposite. My RT60 is around 200 ms across the range which is mixing room dry and just how I like it.

Further, ( in my opinion ) 2 channel playback needs some reflections from the sidewalls to fill up the flaws in the stereo system - utimately about 20 ms delayed reflections , meaning you need a big listeningroom.

I think you are a classical music listener? I recall Toole likes his envelopment and along with Rubinson goes on about the flaws of stereo vs multi-channel which I'm sure is applicable to their use cases. I rarely listen to recordings of live performances though (a bit of C20/21 avant-garde is all) so I mostly keep the vermouth out of my audio cocktail.

The euphonic side wall reflection vs general reverb time issues are somewhat distinct however. I like a bit of the former for sure.

 

[JP78]

I will give you a short answer to your question: If your room doesnt allow you to sit in the sweet spot in front of the speakers, then the stereosound will be very bad and any room correction is a waste of both time and money. Get your loudspeakers and listeningposition perfect first, then start fiddling with correction programes.

If WAF is the problem, or the room estetics, you can forget having a good sound.
You seems to have a big room ( which is good for sound ) so Im sure you can find a solution.

Thanks @Tangband.
I agree to your general tendency, and good is definitely possible. Reason I'm exploring is simply that I bought a device that allowed me to connect my Counterpoint DA-1 OE as a DAC that comes with this capabilities so I try to explore. You would be surprised how good it sounds (with no correction at all), I have separate listening room in the same house, so I have something very nice to compare. Would love to invite you over, but there is some thousand miles between us .

I moved my hifi around a lot to come to the current quality - its certainly not as my main setup in a perfect room, but positioning it in the middle is a decent alternative, tested out and proven it self. I use a large rug in front, a wall absorber in the back - and months of repositioning. It's old gear but does well (Sonusfaber Electa Amator II, a Counterpoint NPS 100e, the DAC and Roon capable device with DSP and digital passthrough and a TEAC VRDS 10 connected).

And I agree, sitting in front always rocks - but mate, there is life and this is not always possible - so I look for the next best.

@Axo1989
That's what I'm exploring, that device comes with a parametric EQ and Dirac Live 3x. I never used any of it, so I'm just wondering what it could do to a room acoustic like mine. In my main listing room I worked with deflectors and positioning, rugs etc to get to my perfect LP. It's a fact that I can't do this upstairs. with kids and family I still try to maximise my listening experience in the area we life most. I agree to both of you Axo/Tangband, and that's the situation I'm in.

So the question is not what is best - but what is best for the situation.
I would be interested in your opinion:
- i.e. could I measure delay
- i.e. would I just change certain frequencies
- I'm just probing if any of the parametric EQ and or Dirac would be usable / I'm decently happy with what I have, it came with a micro to measure, but I simply wouldn't understand what to measure or how to position the points to measure as all guides point to a "sit in front", maybe its a pointless question then.

Or is your general advice dont bother, and life with what I have? Anyhow, thanks for your input so far, I appreciate.

 

[Axo1989]

So the question is not what is best - but what is best for the situation.
I would be interested in your opinion:
- i.e. could I measure delay
- i.e. would I just change certain frequencies
- I'm just probing if any of the parametric EQ and or Dirac would be usable / I'm decently happy with what I have, it came with a micro to measure, but I simply wouldn't understand what to measure or how to position the points to measure as all guides point to a "sit in front", maybe its a pointless question then.

I use Fuzzmeasure and Sonarworks, most here describe using REW and Dirac so others would be better to describe software specifics. But in general terms you can do everything with the latter softwares (I like the former for use-of-use). I also use full-range EQ rather than parametric as I prefer not to tweak (once I start down that road, I can't stop). But you can do either in Dirac (or both).

Measuring reverb time (RT60) in the room and frequency response (FR) within the listening area will be informative in any case, so I'd start there.

I'd say for an informal layout still try to get a stereo triangle for your speakers and part of the listening area if possible. I can't precisely visualise your room layout from the description so if you can do a sketch/plan people here will give better advice. But just measure as is for now.

In Dirac use the options for a larger listening area (there should be one that uses multiple mike positions) and apply a common or default curve and see if you like it. There may also be an option for time correction for an off-centre listening position. You should be able to toggle these on/off to compare.

If the FR curve shows particular peaks you can correct for those using parametric EQ if you like that approach. I wouldn't stress too much if you are happy now, but if these things interest you then try them.

 

[Tangband]

Thanks @Tangband.
I agree to your general tendency, and good is definitely possible. Reason I'm exploring is simply that I bought a device that allowed me to connect my Counterpoint DA-1 OE as a DAC that comes with this capabilities so I try to explore. You would be surprised how good it sounds (with no correction at all), I have separate listening room in the same house, so I have something very nice to compare. Would love to invite you over, but there is some thousand miles between us .

I moved my hifi around a lot to come to the current quality - its certainly not as my main setup in a perfect room, but positioning it in the middle is a decent alternative, tested out and proven it self. I use a large rug in front, a wall absorber in the back - and months of repositioning. It's old gear but does well (Sonusfaber Electa Amator II, a Counterpoint NPS 100e, the DAC and Roon capable device with DSP and digital passthrough and a TEAC VRDS 10 connected).

And I agree, sitting in front always rocks - but mate, there is life and this is not always possible - so I look for the next best.

@Axo1989
That's what I'm exploring, that device comes with a parametric EQ and Dirac Live 3x. I never used any of it, so I'm just wondering what it could do to a room acoustic like mine. In my main listing room I worked with deflectors and positioning, rugs etc to get to my perfect LP. It's a fact that I can't do this upstairs. with kids and family I still try to maximise my listening experience in the area we life most. I agree to both of you Axo/Tangband, and that's the situation I'm in.

So the question is not what is best - but what is best for the situation.
I would be interested in your opinion:
- i.e. could I measure delay
- i.e. would I just change certain frequencies
- I'm just probing if any of the parametric EQ and or Dirac would be usable / I'm decently happy with what I have, it came with a micro to measure, but I simply wouldn't understand what to measure or how to position the points to measure as all guides point to a "sit in front", maybe its a pointless question then.

Or is your general advice dont bother, and life with what I have? Anyhow, thanks for your input so far, I appreciate.

….You can always try with room correction and If the music sounds better - it is better .
If it sounds worse - you can turn it off completely.

 

[JP78]

Thanks both - encouraging I'll just start to play around.
I'll report back after some weeks about what I learned,
thanks for the exchange