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Genelec GLM Review (Room EQ & Setup)

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amirm

amirm

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sarumbear

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This is a misunderstanding of what DRC/DSP FIR filtering products actually does... There is indeed filter insertion loss as there is no boosting, but it is typically 5 to 7 dB of loss. But can easily be recovered by adding some digital gain. It is a completely different paradigm than PEQ.
I’m sorry but the graph you posted shows up to 25dB attenuation was used to flatten the curve. What am I missing?
 

Dimifoot

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MMM was not used for GLM so I am not sure why you are suggesting that. Also, MMM technique's job is to filter the response, not to provide better results.
Because we have two ears, approx.20cm apart, and we don’t stand absolutely still while listening to an album.
 

Vini darko

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Very intresting looks alot easier than my cumbersome 31 band GEQ.
Thanks for the reveiw Amir.
Zeos did a video on this set up wich made it look both complex and easy at the same time :D
 

mitchco

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I’m sorry but the graph you posted shows up to 25dB attenuation was used to flatten the curve. What am I missing?

The after response data was offset by 25 dB in REW so one could clearly see the visual difference. Has nothing whatsoever to do with the actual FIR filter attenuation, which in this specific case was about 6 dB.
 

tktran303

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Mitchco,

I don’t think you’re going to change Amir’s response on this matter; this is a review to guide a purchase decision not a comprehensive discussion on room/speaker correction; as in your book

https://www.amazon.com/Accurate-Sound-Reproduction-Using-DSP-ebook/dp/B01FURPS40

Clearly amir has set it up as is and reviewed it for a single mic spot, which experienced users will understand that it accurate for one ear, but not the other. It is a quick and dirty “room correction” .

Users who have experienced room correction using products like Dirac or Acourate (almost a decade old now) know of their benefits of measuring over multiple points vs the single mic point correction, and using mixed FIR and IIR filters to correct for all frequencies; whilst minimising delays.

Be careful you may find yourself banned.
 
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sarumbear

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The after response data was offset by 25 dB in REW so one could clearly see the visual difference. Has nothing whatsoever to do with the actual FIR filter attenuation, which in this specific case was about 6 dB.
I was talking about the difference I marked in the attached image.
0D0A7A5C-237D-442A-BCF2-6DE83652628E.jpeg
 

mitchco

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I am well aware of this as I said "transition frequencies." Plural. That does not change the nature of the task. Tiny corrections through FIR filter or PEQ makes little to no audible difference and even when audible, a listener needs to apply judgement to them. With PEQ like solutions like GLM, it is dead simple to turn the correction filter on and off and judge the results blind or otherwise. Convolution type filters tend to be all or nothing as far as UI, and also very slow to change depending on system making such comparisons very difficult if not impossible.

As a general rule, superbly built speakers are of no need of correction in higher frequencies other than overlaying a target curve which should to be taste.

You may have forgot I developed a convolver that switches level matched FIR filters instantly so making such comparisons is a breeze. And works with most music players, DAW's and system wide audio on Mac or Windows.

Re: As a general rule, superbly built speakers are of no need of correction in higher frequencies other than overlaying a target curve which should to be taste.

Yup, believe it or not, we are saying the same thing :)

Re: Tiny corrections through FIR filter or PEQ makes little to no audible difference and even when audible, a listener needs to apply judgement to them.

We will have to agree to disagree. The point in fact is PEQ can't make "enough" tiny corrections. 5 band PEQ compared to FIR filtering with typically 0.7 Hz frequency resolution is again something completely different, which is both measurable and audible.
 

mitchco

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I was talking about the difference I marked in the attached image. View attachment 151783

Again, no, 25 dB of attenuation was not applied to achieve this. There is indeed 25 dB of peak to peak variation in the response and typical of about every room measurement I receive and I have received hundreds from around the world. But again, this is not how digital room correction works using FIR filters. As @tktran303 has suggested, let me take this on in another thread or better yet, a video I have been planning for this precise topic. of how state of the art FIR filtering actually works. So I will bow out of this thread as it is a review of a product and get back to you with a walkthrough so folks can see how it is achieved. Cheers.
 

Music1969

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No offence to you @amirm, fine review. But I don't get it. How is this room eq? I would expect something more like this:

View attachment 151767

This is what one should expect from "state of the art room" eq. As I have shown in multiple posts on ASR, it is not just at one listening point either...

There is a big difference between PEQ and room eq that is based on high resolution FIR filtering. I would be happy to prepare some FIR filters for you if you send me some REW measurements.

Kind regards,
Mitch

Not enough "taps" to do anything in the most important bass region with GLM?

Looking at before and after, it's almost enough to say GLM does nothing. The small differences probably just small position change?
 
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enricoclaudio

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I would like to see a comparison between the Genelec GLM and miniDSP SHD with Dirac Live. I'm planning on upgrading my Dynaudio BM5 MKIII with Genelec 8341s by the end of next year. My only concern is how I can add my Rythmik Audio E22 subwoofer with the Genelec GLM. As far I know the only subwoofers you can use with the GLM are the Genelec Smart subwoofers.
 

HiFidFan

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As far I know the only subwoofers you can use with the GLM are the Genelec Smart subwoofers.

My research (been looking at SAM monitors for a few months) leads me to believe that this is true.
 

ernestcarl

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MMM was not used for GLM so I am not sure why you are suggesting that. Also, MMM technique's job is to filter the response, not to provide better results.

From my experience, MMM can also provide better results (to some degree) precisely because it filters the response.
 
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Because we have two ears, approx.20cm apart, and we don’t stand absolutely still while listening to an album.
The moment you worry about such things, you need to throw out the measurements and use your ears. No single microphone is going to represent your two ears and the brain. Correction here is at low frequencies only which doesn't involve such psychoacoustics (due to very long wavelengths involved).
 
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amirm

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From my experience, MMM can also provide better results (to some degree) precisely because it filters the response.
It is just another average (easier for humans to see, but lower resolution). This is needed if you want to interpret the tonality of higher frequencies. But in bass, you want high resolution to find the exact frequencies of peaks and you want to be very careful in providing any type of averaging, spatial or otherwise.
 
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amirm

amirm

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Be careful you may find yourself banned.
You should be careful to not get banned with such nonsense commentary. Keep it out of this forum. I know Mitch and unlike you, he has earned his spot here.
 

echopraxia

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Note that the overall signature was somewhat bright as is typically the case when you take out the excess bass. Genelec provides dual shelving filter overrides to boost the lows and reduces the highs. This is limited 3 dB max correction however. I found the effect subtle even at maximum correction and wanted to have more room for adjustment.
Note that you actually can fully manually control the underlying shelf filters to achieve much larger (as well as more granular) corrections, just not via the “Sound Character Profile” menu for some reason. All that menu does is assign a few preset values to the shelf filter slots.

To achieve full control of there parameters, you have to take a completely different approach that is not intuitive IMO: You first have to select “None” in the “Sound Character Profile” menu, after which point the shelf filters per speaker will now become fully user-editable. You can then enter in any parameters you want for the shelf filters after clicking on each speaker. When you use the “Sound Character Profile” menu, all it does is overwrite these shelf filter parameters and disable editing them by hand in each speaker’s filter editor window.

I currently use this approach to manually tune the shelf filters, since in my current room I find the sound character presets to be either too bright or too dark, so I tune it very precisely by just adjusting these shelf filters manually for each speaker.
 
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beeface

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Genelec must have a lot of good people making good decisions are their company.

NOW, if only made made speakers that looked good too!
I don't mind the industrial design, especially in a white or custom finish. I'd concede they're not the prettiest, but there's definitely uglier loudspeakers out there IMO.
 
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