Does GLM alter the sound other than trimming peaks/boosting nulls?

[RobL]

On a whim I turned off GLM on my 8361’s and reverted to simply using the DIP switches to trim the bass. I’ve had them like this for a few days now and I’m finding I actually prefer this to what GLM was doing. They sound much more “interesting” to me. Now, I had to shelve down the highs a few dB down after GLM calibration as they just seemed too much, but playing these sans GLM I don’t get the same impression from the highs, they just sound right to me.
I think it’s probably the uncut highs that I’m enjoying now but what am I doing wrong in GLM that forces me to trim them?
Anybody else found they enjoyed their speakers without GLM over with it?

 

[Joachim Herbert]

With GLM active there may be the impression of less bass, which might be a reason to dial down treble to "balance" the sound.

I for one enjoy GLM very much.

 

[Sancus]

Why not just take a quick MMM measurement with it on and off and find out the answer? Then you can tune your GLM response. Amount of bass and treble is a matter of taste and specific recordings anyways.

 

[Trell]

For your 8361 there is this, perhaps other settings as well.

>>>7.14.7 Extended Phase Linearity

The option selects the Extended Phase Linearity ‘ON’ or ‘OFF’ and is effective when you are using
The Ones monitors (8331A, 8341A, 8351B or 8361A) in the group.
The ‘ON’ setting maintains the input-to-output delay constant down to about 100 Hz and has a
slightly higher input-to-output latency. The ‘ON’ setting is a default setting for The Ones in GLM
and will only affect The Ones models.
The ‘OFF’ setting keeps the input-to-output delay constant down to about 500 Hz and has a low
input-to-output latency.
If using The Ones with other models that have wide linear phase characteristics, the Extended
Phase Linearity (ON) is highly recommended.
Note: Firmware may have to be updated to enable this feature.<<<

https://assets.ctfassets.net/4zjnzn055a4v/7jLw9cbFMRvbkbxmQKqNVN/f340eda426e2b5c2c3354fd5424fcd08/GLM4_System_Operating_Manual_2021-07-14_-_FINAL.pdf

>>>Phase linear performance across both cross-over points of a 3-way coaxial monitor raises the bar
for uncompromised reproduction even further, including improved stereo imaging focus and precision,
enhanced off-axis performance and more stable Ultra Nearfield (UNF) imaging. Because Genelec two-way Smart Active Monitors already feature linear phase down to about 100 Hz, GLM 4.1 therefore also
improves the performance of systems that blend The Ones (8331A, 8341A, 8351B, 8361A) and other Smart Active models. <<<

https://support.genelec.com/hc/en-us/articles/4411087024786-What-are-the-benefits-of-the-extended-phase-linearity-mode-EPL-

 

[RobL]

Why not just take a quick MMM measurement with it on and off and find out the answer? Then you can tune your GLM response. Amount of bass and treble is a matter of taste and specific recordings anyways.

I am playing around with the speakers now, I recalibrated and took off the high shelf in GLM I had attenuating the highs. GLM’s highest filter is at 676hz (-0.9 dB), no correction applied above that but (for example on the song “Time On My Hands” by Asgeir) when I switch back and from corrected to not using the Stored DIP switch there is a considerable difference in “air” in the singers voice with the uncorrected version sounding much nicer to my ears.
I don’t have time to play around with REW at the moment but will try to find any differences.
Also, has GLM always applied correction above Schroeder? I don’t remember it correcting that high before.

 

[Joachim Herbert]

Did you ever generate a GLM report? This gives pretty comprehensive insights on room interaction and might be helpful to understand what's going on.

Also, did you try to delete the filters GLM generated above say 300 Hz?

 

[RobL]

Did you ever generate a GLM report? This gives pretty comprehensive insights on room interaction and might be helpful to understand what's going on.

Also, did you try to delete the filters GLM generated above say 300 Hz?

No, I didn’t try deleting any filters. I’ll give it a try when I have some time to mess with it.
GLM certainly improves the bass, I’ve no doubt about that. I just find there’s something more compelling when listening with the sound uncorrected. I actually found a reviewer who had a similar experience to mine HERE.

I’ll quote the review:

In almost every loudspeaker setup, spatial information contained on the recording mixes with that which is caused by one's own listening room - the "heard room" is a mix of both. In many cases, this results in an authentic mix that gives me, as a listener, the illusion of being in the same room where the recording was made. This also works with the "unadapted" Genelecs.

After measuring the room, my perception is different: it seems as if my listening room is no longer part of the spatial illusion, rather I am looking at the acoustic events from the outside, am more of a viewer than a participating audience. On the one hand I get an even more concrete picture of the recording and its spatial conditions, on the other hand I am more on the outside, in the observer's position. This is probably more correct for assessing the recording - but it seems less authentic to me in the sense of "natural hearing".

 

[Joachim Herbert]

Just read the review (again). Unfortunately GLM does not take the room out of the equation as described by the reviewer.

Again, I recommend to generate a GRADE report that shows what is going on in your room. This will help to understand what you are experiencing. The report provides great explanations to the findings.

 

[RobL]

Just read the review (again). Unfortunately GLM does not take the room out of the equation as described by the reviewer.

Again, I recommend to generate a GRADE report that shows what is going on in your room. This will help to understand what you are experiencing. The report provides great explanations to the findings.

I’ll generate a report but won’t it only show me early reflections, reverberation, itu compliance etc. that would be identical corrected or not?
I agree that GLM doesn’t make the “listening room no longer part of the spacial illusion”, but he does notice a less authentic listening experience even if his explanation is incorrect.

 

[Trell]

I’ll generate a report but won’t it only show me early reflections, reverberation, itu compliance etc. that would be identical corrected or not?
I agree that GLM doesn’t make the “listening room no longer part of the spacial illusion”, but he does notice a less authentic listening experience even if his explanation is incorrect.

Do you use SinglePoint or MultiPoint when calibrating with GLM? There is also the option during calibration to use Individual EQ or Symmetrical EQ as well. I assume you used Cloud AutoCal2

 

[Joachim Herbert]

I’ll generate a report but won’t it only show me early reflections, reverberation, itu compliance etc. that would be identical corrected or not?

It shows what listening experience you can reasonably expect. That is a great starting point.

I agree that GLM doesn’t make the “listening room no longer part of the spacial illusion”, but he does notice a less authentic listening experience even if his explanation is incorrect.

Expectation bias. He is a reviewer with a background in high end audio, so room correction must have a negative impact. Somehow.

But hey, it's just fine to enjoy these speakers without room alignment.

 

[RobL]

Do you use SinglePoint or MultiPoint when calibrating with GLM? There is also the option during calibration to use Individual EQ or Symmetrical EQ as well. I assume you used Cloud AutoCal2

I use single point-individual calibration with cloud autocal2. I’m gonna have to fire up REW and take a few readings to see what differences are there above Schroeder frequency. Will try to do that soon.

 

[Trell]

I use single point-individual calibration with cloud autocal2. I’m gonna have to fire up REW and take a few readings to see what differences are there above Schroeder frequency. Will try to do that soon.

I think it’s worth trying out multiple points calibration with GLM.

 

[RobL]

Expectation bias. He is a reviewer with a background in high end audio, so room correction must have a negative impact. Somehow.

I don’t know if you can simply write his experience off as expectation bias, I might have agreed if I didn’t compare them myself. Can we just take for granted that they will sound superior because a graph looks better to the eye?

But hey, it's just fine to enjoy these speakers without room alignment.

Yes, I suppose but I also spent $400 on a Room Correction system that should improve my experience, right? I still hope there is something I’m overlooking (wouldn’t be the first time, lol). So far my experience with room correction is 0-2. I had Anthem ARC with my previous system but had to stop using it as it seemed very erratic…certain bands would go in and out of attenuation, or so it seemed to my ears.

 

[Joachim Herbert]

Seems I cannot provide any useful information, so good luck to you!

 

[bodhi]

Yes, I suppose but I also spent $400 on a Room Correction system that should improve my experience, right? I still hope there is something I’m overlooking (wouldn’t be the first time, lol). So far my experience with room correction is 0-2. I had Anthem ARC with my previous system but had to stop using it as it seemed very erratic…certain bands would go in and out of attenuation, or so it seemed to my ears.

No, you spent money for Room Correction system that modifies frequency response in a room in a certain way that is widely accepted as "more correct". But maybe this preference is for studio work since from experience I know many people cut the treble by 2-3dB for music enjoyment purposes.

I had bass boosted by 3dB from 100Hz and treble cut 3dB for some time and that sounded more "correct". Then I decreased the cut to 1dB and was amazed how much more correct it sounded, more detail and all. I think removed the shelf couple of weeks back and still sounds better. I also think that when after I while I experiment with it again I'm amazed how natural -3dB cut sounds and so on ad infinitum.

 

[RobL]

No, you spent money for Room Correction system that modifies frequency response in a room in a certain way that is widely accepted as "more correct". But maybe this preference is for studio work since from experience I know many people cut the treble by 2-3dB for music enjoyment purposes.

I had bass boosted by 3dB from 100Hz and treble cut 3dB for some time and that sounded more "correct". Then I decreased the cut to 1dB and was amazed how much more correct it sounded, more detail and all. I think removed the shelf couple of weeks back and still sounds better. I also think that when after I while I experiment with it again I'm amazed how natural -3dB cut sounds and so on ad infinitum.

What is baffling me is that with no treble cut in GLM, only whatever filters it applies on it’s own, I can hear a significant difference in mids and highs with the uncorrected sound seeming more appealing to me. This shouldn’t be if GLM isn’t messing with things outside it’s chosen filters.

 

[Joachim Herbert]

Taking out the room modes changes the tonal balance, making the system sound "thinner" or brighter. You can try for yourself adding the respektive filters. Even simpler: Run GLM without any filter at all and compare GLM on/off.

 

[Rntlee]

Measured my right speaker in REW with GLM (green) and without GLM (blue)...what the heck is GLM doing? no wonder I find it dull sounding!

No filters or shelves other than what GLM applied for correction.

 

[thewas]

Measured my right speaker in REW with GLM (green) and without GLM (blue)...what the heck is GLM doing? no wonder I find it dull sounding!

View attachment 300070

No filters or shelves other than what GLM applied for correction.

Could you please post the filters applied by GLM, looks like 2 shelving ones above 500 Hz?