Genelec GLM Review (Room EQ & Setup)

[thorvat]

Not necessarily and depending on how much you will later move your head, for example for monitoring usually small distances are recommended.

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Most folks here are not monitoring but listening, and most of those who monitor are professionalists who don't need our advice how to spatially average when doing room EQ.

Btw, shoulder width of that sofa is more likely to be larger than 60 cm, certainly not 30cm, otherwise you won't be able to fit in it.

Regarding moving my head, I like to enjoy glass of wine and a cigar while listening and that accounts for more than 30cm of movements. I'd say it's the same with most of the people as nobody probably uses listening chair with seatbelt.

 

[Frgirard]

Most folks here are not monitoring but listening, and most of those who monitor are professionalists who don't need our advice how to spatially average when doing room EQ.

professionals see EQ as a problem, not a solution.
This product like sonarwork, Arc... are intended for home studio owners.

 

[Purité Audio]

professionals see EQ as a problem, not a solution.
This product like sonarwork, Arc... are intended for home studio owners.

That simply isn’t true, every engineer I know uses EQ, low bass is extremely difficult to deal with even in a ‘treated’ room.
Keith

 

[Frgirard]

That simply isn’t true, every engineer I know uses EQ, low bass is extremely difficult to deal with even in a ‘treated’ room.
Keith

what does it change ? of two evils, obviously the less bad is chosen, the money is the king.

 

[Tangband]

My advice to use GLM :

1. Do a single microphone measurement, but left and right loudspeaker separate ( can be done in GLM where the sine-sweep goes twice ) . Measurement mic should be placed where your head is when you listen.

2. After that , go in manually in GLM and set every correction thats higher than the rooms fundamental resonances, to zero. Meaning : set every correction higher than 80 Hz to zero.

2. Go in manually in GLM and adjust all the corrections beyond 80 Hz to half of the measurement values. If GLM wants to correct -10 dB at 44 Hz , then you print -5 dB instead.

3. Manually use GLM and shelving filtering for frequencies from 150 Hz and downwards , set to + 4 and up to + 7 dB bass gain . This can be done by lowering all the frequencies above 150 Hz , ie using reversed shelving .
Just go in manually and adjust it with the shelving filter. Your eyes see the room and your brain expects some room-gain in the bass area. You need more bass than a flat frequency response ( as Toole and more have suggested ) .

4. If listening to the 83xx series as home-hifi speakers ( and not nearfield ) , go in manually in GLM and do a shelving from 2500 Hz and upwards, - 1 dB .
In some cases, thats gonna make the sound better if you listen from , say , 3 meters away.

Enjoy the high-end sound result .

 

[q3cpma]

2. After that , go in manually in GLM and set every correction thats higher than the rooms fundamental resonances, to zero. Meaning : set every correction higher than 80 Hz to zero.

You have a castle or something? Because "normal" rooms' Schroeder frequency is nearer to 200 Hz than 80.

 

[Frgirard]

3. Manually use GLM and shelving filtering for frequensys from 150 Hz and downwards , set to + 4 and up to + 7 dB bass gain . This can be done by lowering all the frequensys above 150 Hz , ie using reversed shelving .

on reflections like the SBIR, you do nothing

 

[Frgirard]

You have a castle or something? Because "normal" rooms' Schroeder frequency is nearer to 200 Hz than 80.

200 Hz ? 300 Hz see 600 Hz. the schroeder frequency doesn't existe in domestic room. Replaced by the area transition.

 

[q3cpma]

200 Hz ? 300 Hz see 600 Hz. the schroeder frequency doesn't existe in domestic room. Replaced by the area transition.

Well, it sure isn't a single frequency, but I'd fear screwing the direct sound by EQing as high as 600 Hz.

 

[Tangband]

on reflections like the SBIR, you do nothing

Well, I´m thinking Its better to move the loudspeakers out of the front wall ( more than 1,1 metre ) or put them very close to the wall with some acoustic material right behind the loudspeaker, than trying to compensate with eq for SBIR .

Putting the Genelecs close to the wall, you can use shelving manually in GLM from about 700 Hz and downwards to compensate for the extra gain from the wall. The damping material behind the speaker should then be as the small picture shows.

I´m really a fan of only correcting the fundamental resonanses in the room, not the reflections. Others may think differently.

 

[thewas]

Most folks here are not monitoring but listening, and most of those who monitor are professionalists who don't need our advice how to spatially average when doing room EQ.

Btw, shoulder width of that sofa is more likely to be larger than 60 cm, certainly not 30cm, otherwise you won't be able to fit in it.

Regarding moving my head, I like to enjoy glass of wine and a cigar while listening and that accounts for more than 30cm of movements. I'd say it's the same with most of the people as nobody probably uses listening chair with seatbelt.

A multipoint or MMM average won't differ significantly in the modal region whether it is 30 cm or 60 cm, also it doesn't mean that a wider one automatically should sound better if you move your head 15+1 instead of 15 cm out of the middle.
By the way personally when I listen on my own its easier to keep my head position quite exactly in the middle (which is also more important for stereo image balance) than in the other 2 axes

Spoiler

especially depending on the glass(es) of wine.

 

[thorvat]

A multipoint or MMM average won't differ significantly in the modal region whether it is 30 cm or 60 cm

That depends on the speaker-room interaction so it varies from case to case. I never use 30cm cube space when doing room EQ unless listening distance is short. Assuming most typical home listening distance (2-3m) you will find quite significant differences between multipoint measurements of the 60cm cube, and all of them would be in the modal region. Some of them would be in the transition region and above 900Hz there would be practically none. If you enlarge the measurement space the differences will grow, but again mostly in the modal region. As room doesn't affect response above 900Hz the differences you will see there would only come as a result of slight HF response change coming from changing the angle of the mic to the speaker (HF roll-off).

And that is the reason why room EQ, which typically affects 20-600Hz region, should always be done based on spatially averaged measurements because room affects that region mostly so you need to average the response in the space you will be using for listening. Width, depth and height of measurement space depend on your listening distance and your listening requriements and typically should be as shown on your sofa pic for a single seat listening.

also it doesn't mean that a wider one automatically should sound better if you move your head 15+1 instead of 15 cm out of the middle.

I need to move more than 1cm to reach my glass of whine and to handle the cigar.

 

[Tangband]

That depends on the speaker-room interaction so it varies from case to case. I never use 30cm cube space when doing room EQ unless listening distance is short. Assuming most typical home listening distance (2-3m) you will find quite significant differences between multipoint measurements of the 60cm cube, and all of them would be in the modal region. Some of them would be in the transition region and above 900Hz there would be practically none. If you enlarge the measurement space the differences will grow, but again mostly in the modal region. As room doesn't affect response above 900Hz the differences you will see there would only come as a result of slight HF response change coming from changing the angle of the mic to the speaker (HF roll-off).

And that is the reason why room EQ, which typically affects 20-600Hz region, should always be done based on spatially averaged measurements because room affects that region mostly so you need to average the response in the space you will be using for listening. Width, depth and height of measurement space depend on your listening distance and your listening requriements and typically should be as shown on your sofa pic for a single seat listening.



I need to move more than 1cm to reach my glass of whine and to handle the cigar.

correcting reflections between 80-600 Hz from listening position , using multi measurements or a single one, always gonna have the trouble that :

1. You mess up the direct sound from the loudspeaker , correcting reflections.

2. you gonna have different results depending on where you sit - 60 cm at one side from listening position the results gonna be worse than any correction at all.

3. Solution : only correct the rooms fundamental resonances from listening position . Dont correct reflections coming from the loudspeakers bouncing on the floor and walls . Work on loudspeaker installation instead. Use absorbers on the walls.

4. Instead - at first : do proper installation of your loudspeaker . Then use the shelving functions in GLM manually between 80-600 Hz to get the right balance .

We have had very good listening results by doing this .

5. It seems that many dont see the difference between reflections ( coming from the speaker bouncing on the walls, roof and floor to the listener ) and resonances (fundamental resonances in a room comes from two solid surfaces - wall to wall, roof to floor , wall to wall ) . There are only three fundamental roomresonances in a rectangular normal room. All below 80 Hz , and that depends on the size of the room. Those three can be corrected without issues.

Correction of those resonances will be good everywhere in the room and has nothing to do with listening position or loudspeaker position .

 

[thewas]

Assuming most typical home listening distance (2-3m) you will find quite significant differences between multipoint measurements of the 60cm cube, and all of them would be in the modal region.

Not in my room, which gives for 30 or 60 cm MMM cube very similar measurements, even actually for single point measurement when done and smoothed carefully as I had shown here.

correcting reflections between 80-600 Hz from listening position , using multi measurements or a single one, always gonna have the trouble that :

1. You mess up the direct sound from the loudspeaker , correcting reflections.

2. you gonna have different results depending on where you sit - 60 cm at one side from listening position the results gonna be worse than any correction at all.

3. Solution : only correct the rooms fundamental resonances from listening position . Dont correct reflections coming from the loudspeakers bouncing on the floor and walls . Work on loudspeaker installation instead. Use absorbers on the walls.

4. Instead - at first : do proper installation of your loudspeaker . Then use the shelving functions in GLM manually between 80-600 Hz to get the right balance .

We have had very good listening results by doing this .

5. It seems that many dont see the difference between reflections ( coming from the speaker bouncing on the walls, roof and floor to the listener ) and resonances (fundamental resonances in a room comes from two solid surfaces - wall to wall, roof to floor , wall to wall ) . There are only three fundamental roomresonances in a rectangular normal room. All beyond 80 Hz , and that depends on the size of the room. Those three can be corrected without issues.

Correction of those resonances will be good everywhere in the room and has nothing to do with listening position or loudspeaker position .

Spot on!

 

[ernestcarl]

I’ve seen some very well respected acousticians that aren’t afraid of equalizing SBIR around 600Hz from a large console, for example. Some form of frequency dependent windowing (filtering) is applied for such things. Obviously, informed judgment has to applied on case by case basis since this correction is likely only made in consideration for a single main listening/working position in said scenario. It’s quick enough to change DSP presets with the push of a button and to audition for oneself the potentially “harmful” effects of this EQ preset vs a milder or limited modal only EQ.

 

[ernestcarl]

I need to move more than 1cm to reach my glass of whine and to handle the cigar.

I like to shift around a lot or lean to one side or the other with my elbow on the armrest and hand to my chin. Even with my nearfield desk setup I sometimes lean very close to the screen, but also, sometimes sit very much further back. So this “optimal” single mic calibration thing just doesn’t sit well with me — pardon the pun.

Though, seriously, who still smokes today?
Even my grandma has already quit the habit.

 

[q3cpma]

I’ve seen some very well respected acousticians that aren’t afraid of equalizing SBIR

? How do you EQ SBIR?

 

[abdo123]

? How do you EQ SBIR?

only the first null is infinitely deep, the other nulls can be boosted if you have the headroom.

 

[Frgirard]

? How do you EQ SBIR?

Like that but the glm doesn't do it and manually it's impossible.

https://gearspace.com/board/showpost.php?p=13868480&postcount=39

 

[Frgirard]

only the first null is infinitely deep, the other nulls can be boosted if you have the headroom.

The problem is that we wanr to treat the reflection of order one not the others.