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New mysterious Genelec monitors

Blockader

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This is different from what Dirac does.

Filters in Dirac correct phase for the speakers+ room while Genelec monitors (and Hedd monitors as well) just use linear phase filters to improve the speaker performance (without any room measurement).
If you place them in any room they’re not minimum phase anymore.

New Dirac ART is hard to beat if it really works as well as advertised.


That’s why everyone should limit the correction range in Dirac or any correction software.
GLM does phase correction between speakers and genelec subs too. That is covered. That been said, no subwoofer, speaker can have min phase behavior.

Talking about phase shifts, please check group delay audibility paper from Genelec. Human hearing is most sensitive to phase shifts around 3000hz. The sensitivity of our hearing to phase shifts around bass is actually very poor.
 

juliangst

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He says in the video that there's a directivity error
Do you agree ?
View attachment 294320
Most Genelec main monitors don't look as nice as The Ones or 8xx0 speakers in frequency measurements.
I don't think those errors are that big of a deal in a real world scenario
 
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Pearljam5000

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Is there any chance the 2L studio will replace all of their 8351+W371 with 8381 ?
square5-1024x1024.jpg
EyI82cxWgAM2tuO.jpeg
Lindberg.jpg
 

Purité Audio

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Colour scheme is hideous.
Keith
 

Blockader

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Is there any chance the 2L studio will replace all of their 8351+W371 with 8381 ?View attachment 294770View attachment 294771View attachment 294772
The Genelec 8381 speaker cannot be considered superior to the 8351 or 8361 in terms of sound quality. In fact, some argue that it is even inferior to other models in the The Ones series. However, where the 8381 excels is in its loudness capability. These speakers are incredibly loud and have constant directivity. In fact, they are the only speakers in existence with constant directivity and the ability to reach 129dB SPL. The closest competitor in this regard is the Me Geithain 800K. Achieving a loudness of 129dB with sine waves is truly remarkable.

Furthermore, the sound of the 8381 differs from the others in the series. The Genelec 8361/W371, for example, exhibits a constant directivity index (DI) behavior(flat directivity index), whereas the 8381 has a constant rising DI(directivity index constantly goes up from bass to treble). During the Harman speaker target research, there were not enough examples of constant DI speakers to measure their preference ratings compared to conventional monopole forward firing speakers. However, a few constant DI speakers like the JBL M2 (constant DI from 1kHz to 9kHz only) and the Revel Ultima Studio (flattish DI due to the rear tweeter, not a true constant DI speaker) scored higher preference ratings than constant rising DI speakers. From what I recall, they scored the highest. I belong to the camp that believes constant DI speakers are superior to constant rising DI speakers, as it also makes more sense from a psychoacoustical perspective. As for examples of constant DI speakers, we have the Gedlee Nathan, KEF Blade Meta 2, Genelec 8361 (especially with W371), Gradient Revolution (generally Gradient speakers), Kii Three, and D&D 8C.
 

juliangst

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Blockader

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Explain the psychoacoustical perspective please.
1687715163704.png

Toole's book 3rd edition, page 169.

In order to precedence effect function effectively, direct sound and reflected sound should share the same tonal balance.

We know that a preferred in-room response is one that exhibits a downward slope as frequency increases. According to Geddes, this is mostly due to having objects around us which are thick enough to absorb high frequencies. This is irrelevant for our topic though, so let's move on.
My Speculation:
Taking into account the preference for a downward sloping response and the need for consistent tonal balance between reflections and direct sound, the result is flat DI speakers with a downward sloping on-axis response:

1687715686105.png

Just a food for thought, do not take what I said too seriously.
 
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Pearljam5000

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Just think about it. He sits maybe ~3m away from the speakers so what’s the point of having 120+ dB speakers ?
Yeah but don't the extra midranges and bigger woofers have extra benefited other than more SPL?
 

juliangst

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Yeah but don't the extra midranges and bigger woofers have extra benefited other than more SPL?
Just higher output. Just look at the measurents for the 8351. Where do they need improvement?
 

TurtlePaul

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Just higher output. Just look at the measurements for the 8351. Where do they need improvement?
The 8081a seems to be able to generate more directivity with a 15" woofer, a very wide traditional baffle and what is likely phase control between the front and side woofers. The directivity of the 8381a seems to reach down to below 100 hz while the 8351b "struggles" to keep directivity below 300 hz. Also, the slot loaded woofers in the 8351b create group delay up to 400 hz which needs to be DSPed out which doesn't effect the traditional woofers in the 8381a.
 

Curvature

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View attachment 294854
Toole's book 3rd edition, page 169.

In order to precedence effect function effectively, direct sound and reflected sound should share the same tonal balance.

We know that a preferred in-room response is one that exhibits a downward slope as frequency increases. According to Geddes, this is mostly due to having objects around us which are thick enough to absorb high frequencies. This is irrelevant for our topic though, so let's move on.
My Speculation:
Taking into account the preference for a downward sloping response and the need for consistent tonal balance between reflections and direct sound, the result is flat DI speakers with a downward sloping on-axis response:

View attachment 294857
Just a food for thought, do not take what I said too seriously.
CD is not the same as the language Toole uses in his book. He usually writes things like "smooth directivity". Constant directivity aims for flat response not only on axis, but also off axis. Since this is really hard to accomplish in practice you end up with a sloping response that somewhere in MF/HF, say due to a waveguide, shows an abrupt change in slope. Take the KEF speaker you posted. At 4kHz, the tweeter responses suddenly transitions to flat. Charles Sprinkle (of JBL, Harman, Kali) finds CD objectionable for that reason (the change in slope).

1687747984498.png


The other main reason that a sloping response occurs in rooms, in addition to absorption, is because of loudspeaker directivity: longer bass wavelengths and omni at low frequencies, with progressively less energy radiated as you move up in frequency.

Edit: Typo and parenthetical comment.
 
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Blockader

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The other main reason that a sloping response occurs in rooms, in addition to absorption, is because of loudspeaker directivity: longer bass wavelengths and omni at low frequencies, with progressively less energy radiated as you move up in frequency.
I haven't phrased it correctly last time, let me try again: During our evolution, we have always been surrounded by objects thick enough to absorb high frequencies, which is why our hearing appreciates a room response with a downward slope more. Our hearing perceives rolled-off high treble as neutral because of this. This is Geddes' speculation

The case you mentioned only applies to forward firing monopole speakers. An omnidirectional speaker with flat on-axis would have flat in room response.(theoretically) Or a perfect dipole speaker with CD from 20hz to20khz with flat on-axis would also have flat in room response. Desirable? No. Just talking about the behavior of speakers here. Needless to say a cardioid speaker or a dipole speaker would be object to SBIR less because directivity index of cardioid and dipole dispersion pattern is about 4.8 whereas DI of omnidirectional dispersion is 0. Dipoles and cardioids interact with the room less around them in low frequencies. Less SBIR is definitely more desirable, you can see how little difference there is between estimated in room response of 8C or Kii Three vs measured in room response.

Constant directivity does not really aim for on-axis flat response. Constant directivity is constant behavior of the frequency dependent off-axis/on-axis ratio.(both rising DI and flat constant DI fit to this definition) Flat on-axis response was preferred on forward firing monopole speakers. We do now know what kind of on-axis response would be preferred on dipole speakers, cardioid speakers, omnidirectional speakers etc. For forward firing monopole speakers though, yep flat on-axis was preferred.

Charles Sprinkle (of JBL, Harman, Kali) finds CD objectionable for that reason (the change in slope).
Yet he designed JBL M2 which had flat DI from 1khz to 9khz and it scored high.
 
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dasdoing

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I think the main reason room responses of a flat speaker seams to slope down is wrong mic. in a highly reflective room you can't use a free field meassurement mic, but most of the cheaper ones are.

out of the box they are close to diffuse field cause of their quase omni behaviour,
but than they provide us calibrations that are meassured in a quase-anechoic room. therefore the HF will be brought down:
diff-vs-free-field-fr.gif


now, a reflective room isn't diffuse field like either. it's somewhere inbetween
 

Blockader

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I think the main reason room responses of a flat speaker seams to slope down is wrong mic. in a highly reflective room you can't use a free field meassurement mic, but most of the cheaper ones are.

out of the box they are close to diffuse field cause of their quase omni behaviour,
but than they provide us calibrations that are meassured in a quase-anechoic room. therefore the HF will be broght down:
diff-vs-free-field-fr.gif


now, a reflective room isn't diffuse field like either. it's somewhere inbetween
basically sound power of forward firing monopole speakers is higher in low frequencies than high frequencies. That's why in room response of well designed monopole speakers exhibit a downward slope towards high frequencies.

On in other words, total acoustic power of bass frequencies is higher than high frequencies even at same SPL levels because of their wider dispersion patterns. Lower frequencies dominate higher frequencies in reflections.
 
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dasdoing

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basically sound power of forward firing monopole speakers is higher in low frequencies than high frequencies. That's why in room response of well designed monopole speakers exhibit a downward slope as the frequency goes higher.

On in other words, total acoustic power of bass frequencies is higher than low frequencies even at same SPL levels because of their wider dispersion patterns. Lower frequencies dominate higher frequencies in reflections.

is that really the case though? narrower dispersion also means that the reflections have more energy. in PA narrow dispersions are used to throw sound farer for example
 

Blockader

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is that really the case though? narrower dispersion also means that the reflections have more energy. in PA narrow dispersions are used to throw sound farer for example
narrow dispersion behavior happens mostly in high frequencies. Because high frequencies have small wavelengths, their radiation pattern tends to narrow down as the frequency goes higher. As long as the speakers are not cardioid, dipole, the woofer is not 17 meters large, or their baffle is not larger than 17 meters, bass waves are omnidirectional.(below 200hz usually but this also depends on the baffle size of the speakers) Basically if the speaker is significantly smaller the wavelengths it is playing, its radiation pattern is omnidirectional. On the other hand, high frequencies' have smaller wavelengths they have very narrow dispersion. What waveguides does it to add diffractions in a controlled way to make the radiation pattern of the speakers wider of narrower.
same spl x larger radiation pattern = higher sound power.
 
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youngho

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CD is not the same as the language Toole uses in his book. He usually writes things like "smooth directivity". Constant directivity aims for flat response not only on axis, but also
Toole usually writes "relatively constant or at least smoothly changing"

Yet he designed JBL M2 which had flat DI from 1khz to 9khz and it scored high.
Many of the top Harman speakers have had what I call stairstep directivity with relatively flat DI between a few hundred and a few thousand hertz, then relatively higher but relatively flat again until 7-10 kHz, then rising after that:



 

Curvature

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I think the main reason room responses of a flat speaker seams to slope down is wrong mic. in a highly reflective room you can't use a free field meassurement mic, but most of the cheaper ones are.

out of the box they are close to diffuse field cause of their quase omni behaviour,
but than they provide us calibrations that are meassured in a quase-anechoic room. therefore the HF will be brought down:
diff-vs-free-field-fr.gif


now, a reflective room isn't diffuse field like either. it's somewhere inbetween
You misunderstand. In the graph what's shown is the response of a pressure microphone, which are used in specific scenarios (like closed box tests). The microphone we use for measurement are free field and do not have that kind of aberration. There's a difference in construction which accounts for the change in response. Pressure microphones are also more directionally sensitive than free field mics.

Constant directivity does not really aim for on-axis flat response. Constant directivity is constant behavior of the frequency dependent off-axis/on-axis ratio.(both rising DI and flat constant DI fit to this definition)
This is perfect CD, taken from Geddes' paper.

1687793220110.png


Another "more feasible" version of the same.

1687793274267.png


Here's his model on a great loudspeaker's polar pattern:

1687793348342.png


I think you're overstating the case when you talk about the "definition" of CD in terms of DI, same as you do for dipole or cardioid speakers "interacting with the room less" (dipoles excite pressure minima where monopoles excite maxima, while cardioid speakers have limited relevance in the modal region of small rooms). Same goes for this overstatement:
We do now know what kind of on-axis response would be preferred on dipole speakers, cardioid speakers, omnidirectional speakers etc.
Unless there have been some kind of preference studies done that I'm unaware of, there are no separate target on axis curves for those speakers.

Almost none of this pertains to a "psychoacoustical perspective" about constant vs. rising DI you wrote about originally.
 

Curvature

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What waveguides does it to add diffractions in a controlled way to make the radiation pattern of the speakers wider of narrower.
Waveguides can only ever constrain radiation. They can never make it wider. What's done for tweeters to widen radiation in the HF is inserting a phase plug. At the crossover waveguides constrain the lower range of the tweeter so it does not destructively cancel with the higher range of the woofer.
 
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