All I am saying is every thing that you site is a broad references like a complete book and you expect me to hunt through it looking for things that support your side of the argument. Give me an example or something. Anything of substance. So far I see you selectively using certain things to support your side of the argument but if I was to bring up that same exact point you would dismiss it as wrong and anecdotal.
Key
Don't know why you want me to repeat what already has been said. You are lacking some basic knowledge. I'm just trying to be helpful and point you in the right direction. Some things can't be explained in a simple forum post because they are too complex. Moreover you expect people to give away their knowledge for free and at the same time you tell them that you won't ever share any of yours?
Earl's paper is 14 pages and free. It doesn't get easier than that. If you want to learn a language then YOU have to memorize the vocabulary.
Don't know why you want me to repeat what already has been said. You are lacking some basic knowledge. I'm just trying to be helpful and point you in the right direction. Some things can't be explained in a simple forum post because they are too complex. Moreover you expect people to give away their knowledge for free and at the same time you tell them that you won't ever share any of yours?
Earl's paper is 14 pages and free. It doesn't get easier than that. If you want to learn a language then YOU have to memorize the vocabulary.
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Hi Key,
If so, you do not have constant directivity...
By definition constant directivity means that on and off axis frequency response are identical, but off axis is predictably attenuated.
Why? Bass can also be constant directivity!
Note, I not fully subscribe to the need for that (you can leave [most of] the baffle step correction and use a wide baffle and you have sensible in-room response).
Yes. An Omni is actually also constant directivity, only it's directivity index is 0dB. In other words as much sound is radiated into any given angle, including away from the listener. So the reverbrant sound field (or in other words the room reverb) will be 6 - 8dB more than neccesary.
On the other hand a well designed speaker with directive bass, midrange and treble will have a DI of at least around 6dB, 8dB is doable. With correct design cardiode low frequency systems can have a 45degree off axis attenuation of 6dB and a rear null of around -20dB.
Suitable midrange and treble systems exist to match that, so we can have a constant of DI of 8dB or, in other words we can reduce the room sound by 8dB with no penalty in frequency response for either first arrival or reverbrant field. The sonic impact is quite stunning.
I always describe as the reverse of Omni's. Omni's always try to cram a large orchestra into a small room, true CD systems simply make the walls disappear. The difference (in really good cases where other things either way have been addressed) between "They are here" (Omni) and "I am there" (CD).
Ciao T
If so, you do not have constant directivity...
By definition constant directivity means that on and off axis frequency response are identical, but off axis is predictably attenuated.
Why? Bass can also be constant directivity!
Note, I not fully subscribe to the need for that (you can leave [most of] the baffle step correction and use a wide baffle and you have sensible in-room response).
Yes. An Omni is actually also constant directivity, only it's directivity index is 0dB. In other words as much sound is radiated into any given angle, including away from the listener. So the reverbrant sound field (or in other words the room reverb) will be 6 - 8dB more than neccesary.
On the other hand a well designed speaker with directive bass, midrange and treble will have a DI of at least around 6dB, 8dB is doable. With correct design cardiode low frequency systems can have a 45degree off axis attenuation of 6dB and a rear null of around -20dB.
Suitable midrange and treble systems exist to match that, so we can have a constant of DI of 8dB or, in other words we can reduce the room sound by 8dB with no penalty in frequency response for either first arrival or reverbrant field. The sonic impact is quite stunning.
I always describe as the reverse of Omni's. Omni's always try to cram a large orchestra into a small room, true CD systems simply make the walls disappear. The difference (in really good cases where other things either way have been addressed) between "They are here" (Omni) and "I am there" (CD).
Ciao T
When did I say that I wasn't going to share? It's just not organized and ready to go yet. I am actively working on my own theory/system and making it as accessible as possible. I share plenty of my ideas here and there on this forum against my more selfish probably better judgement.
This is a good answer and I see where you are coming from. I'm just not so sure in all cases VERs cause image smear as much as a lack of lateral reflections and copies of the sound in general - basically simple stereo without reproduced reflections yields unnatural results, also there is a lack of coverage generally only covering 60degress but in some rare cases extending out 90 degrees from the center degree.
Can you have directional bass? Without advanced technology or a large price tag? Can you achieve constant directivity or is omni more accessible?
I guess I am after an answer to a different question. I don't much care about in room measurements and reflections because it's been my subjective experience that these only effect the FR in terms of what reflections you get from the typical loudspeaker that subjectively sounds good. For me I am looking for the speaker that is easiest to build and at the same time is the easiest for a person's psychoacoustic processor to blank out acclimate to or make invisible.
It's NOT clear to me that only one type of speaker can do this.
Hi,
Sure, it is easy, in technological terms.
Ho, ho, ho.Making demands now.
Actually, making a omni that is really an Omni is seriously non-trivial.
You can arrange reasonable directivity control down to around 200Hz with little trouble (other than some needed EQ). Below that wavelength really get long and we may argue that the room corner acts as waveguide (90 Degrees).
Okay, you just want "no sound overtly coming from the speaker" and "easy to build". Then drowning the speakers sound in even more room sound will do that.
Even better, a Bose 901 style speaker does it very well and is very easy to build, just 9 pcs 4-5 reasonably wide band speaker sealed or in later version reflex, even higher indirect/direct sound ratio than omni's. Okay, some EQ needed, but in this day and age this is trivial.
Of course, the results leave a lot to be desired in recreating the acoustic space or the acoustics of the recording venue, but it does answer your stated required.
Ciao T
Sure, it is easy, in technological terms.
Ho, ho, ho.Making demands now.
Actually, making a omni that is really an Omni is seriously non-trivial.
You can arrange reasonable directivity control down to around 200Hz with little trouble (other than some needed EQ). Below that wavelength really get long and we may argue that the room corner acts as waveguide (90 Degrees).
Okay, you just want "no sound overtly coming from the speaker" and "easy to build". Then drowning the speakers sound in even more room sound will do that.
Even better, a Bose 901 style speaker does it very well and is very easy to build, just 9 pcs 4-5 reasonably wide band speaker sealed or in later version reflex, even higher indirect/direct sound ratio than omni's. Okay, some EQ needed, but in this day and age this is trivial.
Of course, the results leave a lot to be desired in recreating the acoustic space or the acoustics of the recording venue, but it does answer your stated required.
Ciao T
Ich glaub mich tritt ein Pferd.
(I believe I am tread by a horse.)
If you define what happens in a studio is the ideal/original/what has to be achieved at home the discussion is over before it begins or can only be shifted towards a studio forum.
Well I guess I am making exceptions with the high end when I say omni. To me it can be 6dB down @ 10kHz 40 degrees and I still consider it an omni the same way constant directivity speakers are omni past a certain point and we aren't considering them hybrid.
It's not that I want sounds not to overtly come out of the speakers exactly. Because if it's mixed to sound like that with an LCR mixing style then I would expect some stuff to sound that way.
I am working back from the results I have achieved and I guess I am wondering how these results translate to different speakers or if it's just the speakers I use which are giving me the results. The results I am getting I don't think are some "oh the music breathes much better" type of thing. It's like smacking you over the head with a frying pan obviously better reproduction.
What I am working on isn't built around a specific speaker exactly but it's just that I am not sure what contingencies and interactions all types of speakers would have.
It's not that I want sounds not to overtly come out of the speakers exactly. Because if it's mixed to sound like that with an LCR mixing style then I would expect some stuff to sound that way.
I am working back from the results I have achieved and I guess I am wondering how these results translate to different speakers or if it's just the speakers I use which are giving me the results. The results I am getting I don't think are some "oh the music breathes much better" type of thing. It's like smacking you over the head with a frying pan obviously better reproduction.
What I am working on isn't built around a specific speaker exactly but it's just that I am not sure what contingencies and interactions all types of speakers would have.
I don't think it can be defined in any other way. The common stereo or multichannel audio reproduction chain is not capable of recreating the sound field (at your ears) from the original venue. It's the mixing engineer in his specific control room with specific loudspeakers that tries to create something that might or might not sound like reality. The consumer does not know what the engineer intended. So all the consumer can do is to recreate that specific control room or something that represents the average control room. Any different effort will result in something that is no longer accurate. It may sound more "real" but it's certainly not the original.
Best, Markus
so You are probably looking for this:
http://www.diyaudio.com/forums/multi-way/121385-loudspeakers-room-system-41.html#post2088246
only I would suggest Fostex or similar low Qts 8-incher that can be housed in a small and short closed cabinet instead of Visaton in TL
Fostex should be treated in the way I describe in another thread at "fullrange" section of diyaudio, and the thing needs some correction for lifting the bass
but it is much easier to make than folded TL for Visaton
the thing has been called CFS (for "ceiling firing system" aka "ceiling flooder", copyright by Mr el`Ol)
and probably the best placement for it is described in the very first post of the thread
I understand Your point of view
You aim at "accuracy" because You think that it is something achievable, in contrast to "realism" which finally depends on "recording and mixing techniques" so we can do nothing about it at the stage of sound reproduction (what is lost at the stage of production is lost ultimately)
but I sincerely think that in fact it is all quite the contrary
it is rather the "accuracy" that is really unachievable because we have no access to any reference "original sound" necessary to define such "accuracy"
we have no access to that particular "sound field of the mastering/mixing room" that You are speaking of
after all there are various "mastering/mixing room" arrangements and various electronics and monitors
therefore ultimately "accurate" would have to mean "the same electronics and monitors and room arrangement" as the producers has used when making that particular recording
it is something completely unachievable for many obvious reasons
and only "to recreate that specific control room" would be enough, "to recreate (...) something that represents the average control room" would not
but we are not lost, we still have the other alternative "ideal", that of "realism" which is understood as fidelity to the basic elements of real experience of real auditory event
and from that perspective we are not doomed to "whatever is in the recording", doomed too "something that might or might not sound like reality"
and it is not at all about "recreating the sound field (at your ears) from the original venue", it is not at all necessary!
it is about recreating anything sounding like a real sound field
that is necessary and at the same time sufficient for satisfaction of most music lovers
sound sources sounding "like real", space sounding "like real", not necessarily 100% exactly as "original sound sources", "original space" but at least essentially resembling them
You say:
I ask - where is this mythical original?
And who cares for such an original if it is evident for all listeners that in fact it is fake? perhaps nice, perhaps 99% "accurate" but ultimately fake
On the other hand what we all have and which we all can use as a reference is basic real experience of real auditory event
One doesn't need to go to that particular "original venue" to have criteria to assess "realism" of sound reproduction, any similar real auditory event would supply sufficient criteria for telling the real from the fake
because all experiences of real auditory events are the same in their basic structure
and experience of the presence of some real auditory event before us, "the reach-out-and-touch effect", is achievable even in stereo but not by means of standard front-firing speakers
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I wonder why Dr Toole apparently is not "so sure" as well
gedlee said:
but of course - He puts "emphasis on "preference" as opposed to "accuracy"", yes, it is true
nevertheless He bases his statements not on "simple personal impression from a simple listening test" but rather on rigorous multiple tests with many participants
one cannot counter with an argument like "his ideas support Harman products"
also an argument that "His support for this is a little weak and in some points it is contradicted by his own data " misses the point
the point is that scientifically determined normal listener's preference simply contradicts certain interpretation of "the data"
perhaps this interpretation is wrong because as Markus76 put it:
or perhaps this certain interpretation of "the data" harmonizes with preferences of a certain type of listener with certain, peculiar expectations ie. the audiophile
perhaps the problem is that "imaging" is very loosely defined audiophile concept indeed, and especially the so-called "pinpoint imaging" that is not known to be found in nature and that nobody besides the audiophile seem to care about at all?
what if "precise pinpoint imaging" is in reality just an artefact that is indeed produced only when some special conditions are met like "no VERs"?
but then - the real question is who cares? after all an artefact is just an artefact
and high fidelity is something else, it is not about artefacts, is it?
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ps.
as to "the data" argument
I believe that consistent listeners' preferences determined through scientifically rigorous listening tests under controlled conditions also belong to the category of "the data"
moreover, these data seem to me even more relevant than data collected by a microphone under anechoic conditions
after all sense of hearing doesn't work as microphone and listening rooms are rather "echoic" as hell
as to "the data" argument
I believe that consistent listeners' preferences determined through scientifically rigorous listening tests under controlled conditions also belong to the category of "the data"
moreover, these data seem to me even more relevant than data collected by a microphone under anechoic conditions
after all sense of hearing doesn't work as microphone and listening rooms are rather "echoic" as hell
I think I will stick to "what sounds right"
I believe thats about the best one can hope fore
It will also approach "accurate", especially in terms of "beat", "timing", "definition", etc
Well, in fact it covers just about every fancy word existing in audio
But Im not sure we all have the same understanding of the definition "accurate"
graaf, your position sounds about right too
I think we all too often hear bad excuses fore poor sound
Well, maybe we dont even agree on how to define good or poor sound
Please dont tell me there are exact data and specs on that
I believe thats about the best one can hope fore
It will also approach "accurate", especially in terms of "beat", "timing", "definition", etc
Well, in fact it covers just about every fancy word existing in audio
But Im not sure we all have the same understanding of the definition "accurate"
graaf, your position sounds about right too
I think we all too often hear bad excuses fore poor sound
Well, maybe we dont even agree on how to define good or poor sound
Please dont tell me there are exact data and specs on that
Ok, let me try it from a totally different angle
Music can be broken into very accurate mathematic
But music played stricktly that way sound mechanical
A good musician gives the music "soul"
And its by "twisting" the purely accurate
Some are better at it than others
Some never learn it
Other are masters
And thats about what music reproduction is about too
Good music reproduction reveals those fine feeling that a good musician puts into his music
You may call it "nuances"
Funny to think about
Playing music, you better lay off the stricktly accurate
But we need accurate technology to reproduce it
Music can be broken into very accurate mathematic
But music played stricktly that way sound mechanical
A good musician gives the music "soul"
And its by "twisting" the purely accurate
Some are better at it than others
Some never learn it
Other are masters
And thats about what music reproduction is about too
Good music reproduction reveals those fine feeling that a good musician puts into his music
You may call it "nuances"
Funny to think about
Playing music, you better lay off the stricktly accurate
But we need accurate technology to reproduce it
Accuracy has nothing to do with music, the two things are entirely seperate. I can acurately reproduce the sound of war, and that's not music.
We certainly don't agree on accuracy if you think that music or preference has anything to do with it.
With all due respect, no you don't.
You're describing Audio's Circle of Confusion. The solution is standardization.
The optimal reproduction system has to be capable of delivering a wide range of auditory spaces. Realism is only a subset of audio reproduction.
Depends on how real the auditory illusion needs to be. We don't know which subset of listening cues is "right". You hear something real when listening to your omni loudspeakers - I hear something that reminds me of sound perception in concert halls. Not my favorite space to listen to the news.
The original is what was heard by the mixing engineer. His contribution is part of the art. You probably would alter a painting because it doesn't look the way you want it to. I would never do that. I would adjust the lighting until I could see exactly what Picasso saw.
I claim that what you're describing is only one specific auditory event. There are many more. Walk into a field covered in snow and listen: pinpoint localization. It doesn't get more real than that.
By the way, we "learn" auditory spaces. A newborn baby is not able to localize sounds. A great read is Barry Blesser's "Spaces Speak" (Spaces Speak, Are You Listening: book overview).
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Hi,
So, we are not talking about a true omni, but a very generic variable directivity speaker which starts out with 0dB directivity and becomes progressively more directive as frequency rises?
If the change of directivity is fairly smooth without obvious peaks and dips this kind of speaker works okay, much better than a true omni, that is for sure, but much less well than a true constant directivity (including low frequencies) system.
It is also basically the same turned out en masse by the speaker making industry with varying degrees of success.
I have heard many (true) omni's and they always hit me over the head with a frying pan, that is true, but not by how good they are...
In the end it is everyones preference. I have friends who have and actually like Bose 901's and we are still friends and do not continuously argue about Speakers...
Ciao T
Some POST SCRIPVM
BTW, a system with very well controlled directivity and directional bass is the MEG RL-901K, it is a basically conventional large format 3-Way Studio monitor (active) with the LF unit working into a short transmission line / resistive vent and using a suitable EQ for flattening the LF response lost. The DI stays around 8-10db very flat for most of the Audio band.
How this is achieved is of more than passing interest BTW, IMNSHO.
The LF section as said is basically a variation of the U-Frame, giving cardiode LF with a 10dB rear null down to 30Hz (using active cardiode LF systems can get a null better than 20dB BTW) with the maximum null (and hence TL tuning frequency) around 100Hz. The cost is that the speaker needs a fair bit of equalisation below 100Hz to get real bass output, but I can attest it has excellent and very low bass nevertheless.
The midrange is a smallish cone on a narrow open baffle with a rear "muffler" fitted and suspended in front of the LF cone. The result is an essentially flat DI in the coverage range of this cone Driver (550Hz-2.8KHz).
By selecting the right (dome) tweeter the directivity is again well matched to the cone driver, at high frequencies a phaseshield in front of the tweeter actually broadens the dispersion at the cost of some HF rolloff, which is equalised.
If I remember right (this may have changed in intervening years - I remember the technology of the 1980's RL-900 East German Studio Monitor which it is derived from, never opened the new version), the filter was first order around the midrange with derived lowpass and high pass filters for the LF and HF Driver. Analogue all-pass filters where used to correct the delay between the different drivers. The result is also a very good impulse response, something German Studio Monitor designs tended to emphasise since the Eckmiller coax of the late 1930's.
In principle, in an age where Behringer makes very cheap digital crossovers that allow a fair bit of equalisation which can be easily modified for pretty good sound and where "gainclones" make easy and cheap DIY Multiamplification at pretty good quality both easy and cheap it should not be difficult to DIY such a system at a quite reasonable cost, using whatever similar size drivers take ones fancy.
Heck, with cost of Behringers A500 Amp or the Alesis RA500 you can even afford to buy a stack of them and mod them for best SQ instead!
Even more fun, as someone had mentioned standardisation, in the last days of russian communist occumpation of the eastern parts of germany such a standardisation had been achieved,
The basically same frequency response in the mid and high range and (dictated by size as to cutoff frequency) the same DI was shown by all the then manufactured HiFi Speakers AND it was found in the Studio Monitors as well.
The Recordings made and mastered using a MEG RL-900 translated very well into a domestic setting with the BR-25 or BR-50 Boxesm, which used basically the same Midrange and High Frequency drivers as far as cone geometry, general frequency response, waveguide shape etc. where concerned.
In Germany the BR-25 and BR-50 Speakers made in East Germany still hold some degree of "cult" status and the BR-50 was sold as selected (for matched and flattest FR) studio Monitor in the West for obscene sums of REAL money when I first arrived there in early '89.
Shame that all of this went down the tube in the german re-unification, though the east german audio scene has had a late comeback and I am sure it amuses many of us to no end to notice that MEG Monitors are now the most widely used in the public Radio and TV Services in the new unified Germany (even if late, revenge is sweet..)
So, we are not talking about a true omni, but a very generic variable directivity speaker which starts out with 0dB directivity and becomes progressively more directive as frequency rises?
If the change of directivity is fairly smooth without obvious peaks and dips this kind of speaker works okay, much better than a true omni, that is for sure, but much less well than a true constant directivity (including low frequencies) system.
It is also basically the same turned out en masse by the speaker making industry with varying degrees of success.
I have heard many (true) omni's and they always hit me over the head with a frying pan, that is true, but not by how good they are...
In the end it is everyones preference. I have friends who have and actually like Bose 901's and we are still friends and do not continuously argue about Speakers...
Ciao T
Some POST SCRIPVM
BTW, a system with very well controlled directivity and directional bass is the MEG RL-901K, it is a basically conventional large format 3-Way Studio monitor (active) with the LF unit working into a short transmission line / resistive vent and using a suitable EQ for flattening the LF response lost. The DI stays around 8-10db very flat for most of the Audio band.
How this is achieved is of more than passing interest BTW, IMNSHO.
The LF section as said is basically a variation of the U-Frame, giving cardiode LF with a 10dB rear null down to 30Hz (using active cardiode LF systems can get a null better than 20dB BTW) with the maximum null (and hence TL tuning frequency) around 100Hz. The cost is that the speaker needs a fair bit of equalisation below 100Hz to get real bass output, but I can attest it has excellent and very low bass nevertheless.
The midrange is a smallish cone on a narrow open baffle with a rear "muffler" fitted and suspended in front of the LF cone. The result is an essentially flat DI in the coverage range of this cone Driver (550Hz-2.8KHz).
By selecting the right (dome) tweeter the directivity is again well matched to the cone driver, at high frequencies a phaseshield in front of the tweeter actually broadens the dispersion at the cost of some HF rolloff, which is equalised.
If I remember right (this may have changed in intervening years - I remember the technology of the 1980's RL-900 East German Studio Monitor which it is derived from, never opened the new version), the filter was first order around the midrange with derived lowpass and high pass filters for the LF and HF Driver. Analogue all-pass filters where used to correct the delay between the different drivers. The result is also a very good impulse response, something German Studio Monitor designs tended to emphasise since the Eckmiller coax of the late 1930's.
In principle, in an age where Behringer makes very cheap digital crossovers that allow a fair bit of equalisation which can be easily modified for pretty good sound and where "gainclones" make easy and cheap DIY Multiamplification at pretty good quality both easy and cheap it should not be difficult to DIY such a system at a quite reasonable cost, using whatever similar size drivers take ones fancy.
Heck, with cost of Behringers A500 Amp or the Alesis RA500 you can even afford to buy a stack of them and mod them for best SQ instead!
Even more fun, as someone had mentioned standardisation, in the last days of russian communist occumpation of the eastern parts of germany such a standardisation had been achieved,
The basically same frequency response in the mid and high range and (dictated by size as to cutoff frequency) the same DI was shown by all the then manufactured HiFi Speakers AND it was found in the Studio Monitors as well.
The Recordings made and mastered using a MEG RL-900 translated very well into a domestic setting with the BR-25 or BR-50 Boxesm, which used basically the same Midrange and High Frequency drivers as far as cone geometry, general frequency response, waveguide shape etc. where concerned.
In Germany the BR-25 and BR-50 Speakers made in East Germany still hold some degree of "cult" status and the BR-50 was sold as selected (for matched and flattest FR) studio Monitor in the West for obscene sums of REAL money when I first arrived there in early '89.
Shame that all of this went down the tube in the german re-unification, though the east german audio scene has had a late comeback and I am sure it amuses many of us to no end to notice that MEG Monitors are now the most widely used in the public Radio and TV Services in the new unified Germany (even if late, revenge is sweet..
)