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Not mine but that from Toole's research.That is your perrogative.
Not mine but that from Toole's research.That is your perrogative.
First of all: I listened to your Borg this year at the Munich High-End Show and liked it very much, also your "diffusor room" (looked like the hofa diffusors in self built cabins).No, No, it can be done, but it's not easy. 95% of all subwoofers I have heard in the field have been set wrong.
Of course such extreme case will resonate like hell and that will show in the spinorama.Yes if you really want you can build a box out of paper which has not a single resonance which you can easily see in spinorama measurements.
Edit: but obviously there is sound coming out ot this cabinet which is significant.
So, how many speakers did you construct in your life and measured the cabinet output?? It sounds like not so many. Again, the fact that you cannot measure it, does not mean there is no effect. And you have to differentiate the resonance of the cabinet. Standing wave modes are easy to see in impedance or SPL measurements and port resonances as well. But they are obvious (but still not often treated properly). I'm talking here about panel resonances.Yes if you really want you can build a box out of paper which has not a single resonance which you can easily see in spinorama measurements.
Edit: but obviously there is sound coming out ot this cabinet which is significant.
I can’t get the logic there, if any sound is emitting from the cabinet, or say port, it can be an obvious resonance....sorry, but that is not correct.
KEF and Neumann also use such a Klippel laser vibrometer (am sure Genelec too), I have visited both R&D departments.The cabinets of the speakers you named aren't bad but you certainly have other brands which engineer better cabinets and you can measure such things with a laser vibrometer like @Karl-Heinz Fink is using.
I strongly doubt that, a small entry series Genelec (the same like 8030C) recently measured at Stereophile had possibly the cleanest cabinet acceleration spectrum ever measured there, hope KHF will send his Epos there, but I doubt it will happen.I am sure the cabinet of the epos speaker is much better than the small Neumann or Genelec speakers which are limited by its size and weight even they certainly also did some optimization in that regard.
Yes, unfortunately a lof ot the audio "engineering" since the big players left in the mid 80s is either snake oil or putting effort into some directions which have very low impact on the acoustic result and preference but is more just a marketingSo you really think most of the engineers are simply doing snake oil stuff?
I don't see the discussion here getting out of the technical aspect as it should? By the way personally I really enjoy reading the participation of experienced engineers like KHF here and even thanked him for it in a private message.I remember the discussion here when the new ps audio speakers where coming out and all of the measurement ultras tried to bash the speaker right away, because of the history of ps doing none sense audio. https://www.audiosciencereview.com/forum/index.php?threads/ps-audio-fr30-speakers.27160/
So it turns out that the engineer behind the speaker replies in that thread and that he is way more competent than all measurements ultras combined. If you read this thread I feel embarrassed. There is the opertunety to ask a developer about everything speaker related and some people think they have to teach him the right way of doing it. At the same time they don't fully understand the research they are promoting since even the developers behind the research don't work like the ultras think they are working...
I can feel here the same behavior and it is destroying a nice constructive discussion. You all have to be aware that you can learn at least a bit from every other person here, even if you disagree at some particular point.
Contradicted by Dr. Toole (source)....sorry, but that is not correct.If a cabin is not showing any resonances in measurements, it doesn’t matter if the company uses laser or any voodoo. Show the proof that the cabin on the Epos is better or it’s just your feeling which has no place here
....I would not call that "add a subwoofer to your speaker" setup. . I'm in Munich from time to time, sure I can come and visit you......depends a bit on your coffee machine. Multiple subs on a wall can work well....done that in the past with cardioid subs.First of all: I listened to your Borg this year at the Munich High-End Show and liked it very much, also your "diffusor room" (looked like the hofa diffusors in self built cabins).
Therefore I sat a pretty while in the sweet spot (that happens not very often there)
I'm very curious what your ears would say to my system, as I'm using multiple, wallmounted subs and think time alignment /group delay works quite well, but other impressions are important to me and always welcome So if you're in Munich sometime, and you would have some "boring time", I would be pleased to invite you. My coffee Is quite ok
Take a very small 2" wideband speaker and put it in the part of an egg create with proper seal and some paper "bracing" and you would have very hard time to find a distinct resonance, but you have a lot sound transmission and very small resonances.Of course such extreme case will resonate like hell and that will show in the spinorama.
? I was exactly arguing that you can't see all (small) resonances with the spinorama measurements but there is no doubt that these resonances are there and can be measured and be significant, since the human brain is able to detect these even if other sounds are louder.So, how many speakers did you construct in your life and measured the cabinet output?? It sounds like not so many. Again, the fact that you cannot measure it, does not mean there is no effect. And you have to differentiate the resonance of the cabinet. Standing wave modes are easy to see in impedance or SPL measurements and port resonances as well. But they are obvious (but still not often treated properly). I'm talking here about panel resonances.
I don't know how good your setup is, but you can try something. Listen to your speakers and listen to the height of a singer in a track. Use something more simple (High-End Pling Pling) for a start. OK, now you take a heavy book and place it on top of the speaker. Not too thick or big, so it does not change the baffle load for the driver. Now tell me what you hear. If your system is good, you will hear something. Just let me know.
Or you can place the two speakers face to face....as close together as possible. Invert the phase on one speaker (swap the cable) and that cancels out as much as possible of what the active drivers do. Listen to the port output or check if you can hear something coming out of the plastic terminal panel. You can also try a stethoscope and find some spots on the side panels. This is not rocket science and can help you to detect a few things. It costs no money to do.
We use a Laser scanner vibrometer (POLYTEC) and scan the individual panels. We calculate the radiated energy from there. Nowadays, we put a model of the speaker in COMSOL and simulate the output. That works well, and normally, we get the same results with the real sample. This is no voodoo at all...that's the way cars get designed to avoid noise and is one part of what we do outside HiFi.
The Klippel laser vibrometer does not do cabinet walls but only speaker drivers. It should be a Polytec...it's the only one more or less. B&W got one, not sure about KEF. Smaller cabinets make it easier to get them quiet. The accelerometer only shows one spot.....that does not really tell you what is radiated because there might be an area with an opposite phase. The Klippel laser scanner software is very good at predicting the output from the scan. In-phase, out-of-phase and so-called quadrature components are clearly separated. We do something similar with the Polytec....just our own software.KEF and Neumann also use such a Klippel laser vibrometer (am sure Genelec too), I have visited both R&D departments.
I strongly doubt that, a small entry series Genelec (the same like 8030C) recently measured at Stereophile had possibly the cleanest cabinet acceleration spectrum ever measured there, hope KHF will send his Epos there, but I doubt it will happen.
Source: https://www.stereophile.com/content/genelec-g-three-active-loudspeaker-measurements
I am quite sure that in the frequency region where the egg has its first "balloon mode" you will see a change in the frequency response and even impedance. About very small resonances see the quote of Toole that NTK posted above.Take a very small 2" wideband speaker and put it in the part of an egg create with proper seal and some paper "bracing" and you would have very hard time to find a distinct resonance, but you have a lot sound transmission and very small resonances.
You can even use an array of small and light acceleration sensors to do operating modal analysis of vibrating and radiating surfaces, I was doing such often in my past job. Another option that is also used frequently in automotive NVH to detect parasitic sound sources are acoustic cameras which in the end are arrays of microphones which like the NFS use some math to deconvolute the vectors.The Klippel laser vibrometer does not do cabinet walls but only speaker drivers. It should be a Polytec...it's the only one more or less. B&W got one, not sure about KEF. Smaller cabinets make it easier to get them quiet. The accelerometer only shows one spot.....that does not really tell you what is radiated because there might be an area with an opposite phase. The Klippel laser scanner software is very good at predicting the output from the scan. In-phase, out-of-phase and so-called quadrature components are clearly separated. We do something similar with the Polytec....just our own software.
Not mine but that from Toole's research.
....oh sorry; maybe I was reading it too fast.Take a very small 2" wideband speaker and put it in the part of an egg create with proper seal and some paper "bracing" and you would have very hard time to find a distinct resonance, but you have a lot sound transmission and very small resonances.
? I was exactly arguing that you can't see all (small) resonances with the spinorama measurements but there is no doubt that these resonances are there and can be measured and be significant, since the human brain is able to detect these even if other sounds are louder.
So I was trying to put this argument to the extrem with my claim that you can't see obvious resonances with spinorama measurements with a very thin cabinet out of paper but you certainly have sound which is transmitted and therefore you have to have small resonances.
Impedanz isn't included in the spinorama measurements and with bracing the resonances are in in the higher frequencies where there isn't enough power to get very strong resonances.I am quite sure that in the frequency region where the egg has its first "balloon mode" you will see a change in the frequency response and even impedance. About very small resonances see the quote of Toole that NTK posted above.
It says that frequency response matters the most and also that large resonances which are audible can be also seen in them, see above quote from Toole that NTK posted. Also I never said that a horribly ringing loudspeaker will be preferred to one with just a slightly poorer directivity, but that in decent hifi loudspeakers (not some 10€ plastic PC ones) usually the most audible problems which will reduce the preference are frequency response based (so direct and reflected sound) ones.Does it say in his research that ringing and other artifacts that makes the music sound "wrong" or unnatural is preferrable to slightly poorer directivity?
It says that frequency response matters the most and also that large resonances which are audible can be also seen in them, see above quote from Toole that NTK posted. Also I never said that a horribly ringing loudspeaker will be preferred to one with just a slightly poorer directivity, but that in decent hifi loudspeakers (not some 10€ plastic PC ones) usually the most audible problems which will reduce the preference are frequency response based (so direct and reflected sound) ones.
What do you mean with artefacts from processing?I was thinking about artifacts from processing rather than poor cabinets.