The Measurement and Calibration of Sound Reproducing Systems

TheWarrior

TheWarrior

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#21
4 SMALL VENUE SOUND SYSTEMS
Rooms of a size appropriate for stereo or TV entertainment, home theaters, home studios, and recording control rooms do not require massive, highly directional loudspeakers.


Hmm. This seems more of a reflection of modern sensibilities when it comes to speaker size than anything having to do with actual performance benefits. Speakers that are highly directional can be used in lively, untreated rooms to great effect. Here is a piece put together by Bill Waslo over at AVS describing just such an approach. On top of the things he mentions, larger speakers tend to be more sensitive, which pays dividends as well: no need for herculean amplification; such speakers in a domestic environment operate low in their SOA, so cone motion and related speaker induced distortion is greatly reduced as compared to more WAF-friendly small speakers, not to mention more available headroom/dynamic range. In my own experience, big, highly directional speakers, implemented properly, result in some of the most effortless, clear, and natural/lifelike playback of any approach.

Toole is the man, though. Everyone who cares about getting the most out of their rigs should read his book, or at least read this paper very closely. Thanks for posting it, Gene. (Link still broken btw, Jinjuku's works.)

My apologies, but this article by Bill Waslo has absolutely no context and makes incredible 'blanket' statements. What is defined as a 'large speaker'? More than 2 drivers? They certainly do not tend to have easy to drive impedance values, excepting several specific designs (Philharmonic's, for example).

Toole is attempting to explain that the sound heard with in a domestic room is dependent upon the spatial and enveloping information provided by early AND late reflections, and that only proper measurements of the room itself will determine the best course of installation.

Please know that I am learning myself, and am doing my best to absorb the incredible amount of information Toole packs in to his writing. This and my previous response are an attempt to energize the discussion so we can all learn something from his decades of TESTING these principles!
 
jim1961

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#22
  • Benefits of Early Reflections
  • Issues with Auto-EQ
Given the points here Gene wants to focus on, I agree with the second bullet that Auto-EQ is problematic.

The early reflection issue requires much more definition. Firstly, we have to define what is early. Secondly, we have to look at what is the bandwidth or frequency range and amplitude of such reflections. Thirdly, what direction are these reflections coming from.
 
ski2xblack

ski2xblack

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#23
First, 'directional sound' travels along a specific path with minimal dispersion. This is characteristic of a speaker with poor off axis dispersion.
False. Poor off axis dispersion would be irregular off axis performance. A narrow dispersion with uniform response within it's coverage and uniformly diminished off axis performance demonstrates "good" off axis behavior.

LEV - listener envelopment, will suffer as a result.
False, based on an incorrect assumption that narrow dispersion equals poor off axis response. Controlled directivity speakers, implemented properly, create a sense of envelopment superior to wide dispersion speakers IMO. Assuming a speaker with narrow dispersion, but uniform coverage, they can be placed to greatly reduce early reflections while preserving late reflections, which are attenuated and delayed as they have to propagate further. That seems quite relevant in the context of this thread. And the results are quite enveloping. Holographic, even. More direct source, less room influence.

My apologies, but this article by Bill Waslo has absolutely no context and makes incredible 'blanket' statements.
Bill has been involved with SEOS waveguide speakers, and the article was written to help folks implement them properly. I don't really see anything that contradicts Toole's work at all, it just applies it to a niche case of controlled directivity speakers.

What is defined as a 'large speaker'? More than 2 drivers? They certainly do not tend to have easy to drive impedance values, excepting several specific designs (Philharmonic's, for example).
When I referred to large speakers I meant a typical SEOS design, or Klipsch Heritage, or Danley, or any of the reputable controlled directivity speakers. Most of these are both easy to drive and very sensitive. They also tend to be rather large, at least by today's standards, very low WAF. That is their biggest limitation right there.

I've got a pair of JBL lsr monitors in a near field rig. They're great, and quite Toole-ish in their pedigree. Now I can get an equivalent sense of envelopment, allowing a deep glimpse into the mix, and similar involvement of local acoustics (i.e. not much) with the Tempests arranged as described in Bill's piece in a much larger, untreated room.

Hope this post doesn't come off as too "old Klipsch fart" raving, but it seems sorta relevant.
 
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jim1961

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#24
False, based on an incorrect assumption that narrow dispersion equals poor off axis response. Controlled directivity speakers, implemented properly, create a sense of envelopment superior to wide dispersion speakers IMO. Assuming a speaker with narrow dispersion, but uniform coverage, they can be placed to greatly reduce early reflections while preserving late reflections, which are attenuated and delayed as they have to propagate further. That seems quite relevant in the context of this thread. And the results are quite enveloping. Holographic, even. More direct source, less room influence.
A spectrogram is one way to represent reflection energy in the time domain as well as the frequency domain. In my attempt to negate early energy and preserve later energy, my spectrogram looks like this:

https://dl.dropboxusercontent.com/u/41391584/spec 08 21.jpg
 
TheWarrior

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#25
False. Poor off axis dispersion would be irregular off axis performance. A narrow dispersion with uniform response within it's coverage and uniformly diminished off axis performance demonstrates "good" off axis behavior.
Narrow dispersion is what listeners describe as 'beaming.' This is a bad thing!
http://www.soundandvision.com/content/dispersion-show-and-tell#swqkEsLVhrZcowFL.97



Bill has been involved with SEOS waveguide speakers, and the article was written to help folks implement them properly. I don't really see anything that contradicts Toole's work at all, it just applies it to a niche case of controlled directivity speakers.
Nothing against Bill, but the whole page was full of images of arrows coming from speakers. The first premise of that article is much more succinctly explained in Toole's, 'Sound Reproduction' as the 'precedence effect.' When there are two, or more, sound sources yet only once perceived image. Not debating who's right and wrong here, just keeping this discussion on Toole.



When I referred to large speakers I meant a typical SEOS design, or Klipsch Heritage, or Danley, or any of the reputable controlled directivity speakers. Most of these are both easy to drive and very sensitive. They also tend to be rather large, at least by today's standards, very low WAF. That is their biggest limitation right there.
Ok, you meant horns, which yes, are very efficient. Unfortunately I have only heard smaller horn towers, never the 'bigguns' you describe. I can only imagine how well they can fill a room!



I've got a pair of JBL lsr monitors in a near field rig. They're great, and quite Toole-ish in their pedigree. Now I can get an equivalent sense of envelopment, allowing a deep glimpse into the mix, and similar involvement of local acoustics (i.e. not much) with the Tempests arranged as described in Bill's piece in a much larger, untreated room.
Dr. Toole defines the following for use when discussing spatial impression: ASW and LEV

Apparent Source Width: How broad an image is perceived to be

Listener Envelopment: The sense of immersion perceived from the source; this is very limited when describing mono or stereo.

What do you define as near field? I've got a pair of Focal Solo6 Be's that are labeled as near field studio monitors, but sound spectacular in my medium sized room. I would describe their ASW as much broader than their marketing literature would suggest, and even in my treated room provide a deep sense of envelopment.



Hope this post doesn't come off as too "old Klipsch fart" raving, but it seems sorta relevant.
Lol! Not at all! If those speakers didn't make the impact that they did, we wouldn't still be discussing their merits!
 
TheWarrior

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#26
A spectrogram is one way to represent reflection energy in the time domain as well as the frequency domain. In my attempt to negate early energy and preserve later energy, my spectrogram looks like this:

https://dl.dropboxusercontent.com/u/41391584/spec 08 21.jpg

Page 2! (well, pg 513 section 2, lol)

"Sound cues contributing to spatial perceptions are not revealed in steady-state amplitude-response measurements and the lack of directional discrimination makes time-windowed measurements ambiguous. Therefore, it is necessary to understand the spectral and directional properties of the sound sources as well as the sound reflecting behavior of listening venues in order to anticipate acoustical and perceptual events."

Point is, you measured at one location, but have not factored in how the room is affecting the measurement. And I am pretty sure that is a massive echo your measurement picked up!
 
jim1961

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#27
Page 2! (well, pg 513 section 2, lol)

"Sound cues contributing to spatial perceptions are not revealed in steady-state amplitude-response measurements and the lack of directional discrimination makes time-windowed measurements ambiguous. Therefore, it is necessary to understand the spectral and directional properties of the sound sources as well as the sound reflecting behavior of listening venues in order to anticipate acoustical and perceptual events."

Point is, you measured at one location, but have not factored in how the room is affecting the measurement. And I am pretty sure that is a massive echo your measurement picked up!

I only shared one measurement location, that is true. But I know exactly what direction the 25ms bump comes from because it is there by design.

Haas Kicker.

If you would rather know what I have done rather than speculate:

https://www.gearslutz.com/board/stu...817205-my-listening-room-18.html#post11276339
 
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ski2xblack

ski2xblack

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#29
Since the article speaks to the most important aspects of getting good sound, I propose it get's pinned atop the general forum rather than languish unseen, buried down here as it is.
 
TheWarrior

TheWarrior

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#30
Since the article speaks to the most important aspects of getting good sound, I propose it get's pinned atop the general forum rather than languish unseen, buried down here as it is.
With the recommendation of printing it out and taking a hi-liter to it! I have been doing this will all of Floyd's work...
 
Raimonds

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#31
Hello,


I see high interest about the subject here. I would like to offer my expertise collected in 14 years of serving professionals.

Let’s start with discussion with Dr. Floyd Toole about his paper "The Measurement and Calibration of Sound Reproducing Systems":
https://secure.aes.org/forum/pubs/journal/?ID=524

The full version of discussion is available here:
http://aplaudio.com/downloads/Reading_Dr_Toole.pdf

And what can be corrected – loudspeakers or room:
http://aplaudio.com/downloads/Equalizing_loudspeakers.pdf

BR,
Raimonds
 
TheWarrior

TheWarrior

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#32
Hello,


I see high interest about the subject here. I would like to offer my expertise collected in 14 years of serving professionals.

BR,
Raimonds
I don't think Dr. Toole will mind me reposting the response he already made to you:

“A response to Raimonds Skuruls’ comments on my recent paper

I thank Mr. Skuruls for his response to my paper. Dialog is needed on this topic, and that, in part, was a motivation to write it. I am accused of “being skimpy in proposing any real solutions”. I think a cautious approach is necessary in a peer-reviewed paper that is proposing changes to long-established internationally-standardized measurements. In fact, several dimensions to the needed solutions are, I think, unambiguously identified in the paper, and others that need further research are noted. Even in 30 pages (!) something has to be left out. Most of the detailed explanations are in the references, especially in my 550-page book, and the numerous references therein. There is a lot of relevant data relating technical measurements to perceptions. We are close to being able to assert in unambiguous terms what needs to be done, but my “research scientist” caution inclined me to postpone that until some ongoing investigations are complete.

Mr. Skuruls is in the business of selling his devices and services to customers in the audio industry. As such he can choose to ignore the widely-used recommendations from the ITU, ISO and SMPTE that employ calibration methods based on steady-state in-room measurements and minimum-phase equalization. For decades past, and right now, all of these recommendations are being employed in calibrating movie sound dubbing stages and cinemas worldwide, and in setting up listening venues and facilities for broadcasting as well as university research. The widespread assumption is that they are all that is needed to ensure both good and consistent reproduced sound quality.

I am currently engaged in committees looking to update some of these recommended practices, employing improved measurement methods and applying objectives guided by psychoacoustic relationships learned from disciplined, double-blind, listening tests. All of these documents exist because of a belief that the quality of reproduced sound in recording and broadcast studios, dubbing stages, cinemas, and homes should be fundamentally good and similar. Mr. Skuruls appears to disagree, saying: “But it is a well-known fact that the “good” work of a recording engineer (producer) sounds good as a piece of art through any speaker that is used. Of course it is not the same “sound”, but it is the same work of art.” So, he asserts that the “circle of confusion” in Figure 1 of my paper is irrelevant − that it is sufficient to recognize the “melody”, the “rhythm” and “lyrics” of a song, and that the bandwidth, spectrum, linear- and non-linear distortions and sound levels do not alter the “art”. I beg to differ.

At several points in his comments it is asserted that my focus is on consumer products, that “professional” loudspeakers are inherently superior. I admire his faith, but numerous measurements in Section 2.4 and Chapter 18 of my book show that professional loudspeakers are as susceptible to design inadequacies, as are consumer loudspeakers. The best consumer loudspeakers and the best professional loudspeakers, as they measure and sound, are almost indistinguishable. The flawed ones exhibit an infinite variety of misbehavior, not all of which are capable of “correction” after the fact. Identifying and correcting the flaws is made greatly more difficult if the only data come from measurements in reflective spaces.

Mr. Skuruls claims that recording/mixing engineers are unbiased – “as close as it comes to being objective in the absence of a blind test”. The listening ability of recording/mixing engineers was elaborately tested early in my career and published as “Subjective Measurements of Loudspeaker Sound Quality and Listener Performance”, J. Audio Eng. Soc., vol. 33, 1985 (30 years ago!). In those tests, professional recording engineers and producers were mixed in with audiophiles as subjects in double-blind subjective evaluations of loudspeakers intended for use as broadcast/recording monitors. As a result of noting that several of the professionals were unable to repeat their subjective ratings in subsequent randomized presentations, a problem was revealed that is now widely acknowledged, but rarely discussed. Hearing loss is an occupational hazard in the audio business, and, as a result, the opinions offered by people so afflicted are less reliable, and may exhibit more bias than those from people with more normal hearing. The topic is also discussed in sections 17.4 and 19.1.2 in my book. Professional and “amateur” listeners with relatively normal hearing exhibited closely similar preferences in sound quality. Some of the highest scoring loudspeakers in those tests were consumer products. A couple of the recording engineers commented at the end of the tests that they had never heard such good sound before. They had rejected some of their previously favored monitors, even after some repeat tests using their own master tapes. Needless to say, the highly rated loudspeakers exhibited the least-flawed anechoic measurements, which was discussed in the paper, and others that followed.

Section 17.5 in my book shows how both professional and amateur listeners can be biased by visual information about the products they are listening to – we are all human; blind testing is important. Subjective opinions are the basis for evaluating any sound reproducing system, and controlling the variables, including who is doing the listening, is essential. See Figure 17.6 in my book, and Olive, S. (2003). “Difference in Performance and Preference of Trained versus Untrained Listeners in Loudspeaker Tests: A Case Study”, J. Audio Eng. Soc., 51, pp. 806-825. It shows that experience is a significant factor in terms of the consistency and range of sound quality ratings, but that, in the end, the relative ratings of the products are essentially identical for all listeners – that is unless one’s “microphones” (ears) are damaged.

Mr. Skuruls is focused on performing useful in-situ measurements – not a bad thing – but this inclines him to downplay the usefulness of comprehensive anechoic data on loudspeakers. That is fine, but the reality is that anechoic data are required by the designers of the loudspeakers (if not, why not?) and as such should be available. These data can be elaborated to the level of the “spinorama” shown in Figure 20 in the paper. The frequency resolution is not limited by the measurement venue (time windowing),and is sufficient to reveal audible resonances over the entire audible frequency range: see Section 19.2.1 in my book and Toole, F.E. and Olive, S.E. (1988). “The modification of timbre by resonances: perception and measurement”, J. Audio Eng. Soc., 36, pp. 122-142. Such high resolution is “difficult” in non-minimum-phase rooms, so such problems may go unnoticed. The finding that the spectral “bump” is a more reliable indicator of audibility than time-domain ringing is of importance.

The calculation of a sound power estimate is a natural byproduct of doing full anechoic orbits of frequency-response measurements, and is more accurate than a reverberation chamber estimate for devices that are strongly directional, like loudspeakers (at the NRCC I had access to both kinds of chambers). The frequency resolution of the sound power calculation is that of the basic measurements – in this case 1/20-octave – which helps in identifying the presence of resonances – see Figure 21 in the paper.

I could go on, but all that I would say is either already in the literature, or awaits the results of the psychoacoustic investigations needed to fill in the few blanks left in the Journal paper that provoked these remarks. It is hoped that a new generation of peer-reviewed sound quality recommendation documents will emerge at some point. Then Mr. Skuruls may see the “real solutions” he desires – I was not being deliberately skimpy. In the meantime he has created his own solution, described on his website.

Floyd Toole, Nov. 15, 2015
 
Raimonds

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#33
Let`s put everything in one place!


A response to Dr. Floyd Toole`s answer to Raimonds Skuruls comments.


„Cautious approach” – it is a usual thing for a serious sound engineer to make same change and check result. It is true for mixing job and system tuning as well.

The mixing job is about training the decision making skills and ability to keep fresh hearing and thinking.

„My “research scientist” caution” – sound engineers in studio and concert are trained to make decisions (usually artistic) with certainty. The „caution” should be lived in rehearsal time. The certainty must be in use when public performance takes place and any caution should be removed by appropriate work done beforehand.

„He can choose to ignore the widely-used recommendations from the ITU, ISO and SMPTE that employ calibration methods based on steady-state in-room measurements and minimum-phase equalization.”-

Sorry, incorrect. It is not chosen by me. They are my customers who decide to use the tuning and calibration offered. And they results (usually 2 times less work time to finish the work) are encouraging me to keep doing what I am doing.

„Minimum-phase equalization” – sorry, I did not know any tool offering that (except APL). Please correct me if I am wrong!

„long-established internationally-standardized measurements” – Might be they are standardized but do not have force as a law and usually are not in use because the complexity and lack of reliable instruments, repeatable results and laziness of technicians as well. The example, with a cinema operating company FK that had 13 cinemas with 200 screens, is very enlightening. Yes, they used „steady-state measurement” and nevertheless were not able to see out of phase between sub and mids in the interference „noise”. That was nothing close to meeting a standard and having any control on system’s performance.

At the same time, Hollywood based recording studio ( “The Lord of the Rings”, “The Golden Compass”) step by step equipped all three of their mixing rooms with products that meet producers requirements (the standard also). Without saying, their monitor systems were not the cheapest ones.

„The widespread assumption is that they are all that is needed to ensure both good and consistent reproduced sound quality.”

Yes – still an assumption ...

The offer to use an accurate and effective, in time consumption, measurement of Sound Power Frequency Response are not in contradiction to „long-established internationally-standardized measurements”. Especially, when the understanding of need to use multiple measurement points to get some „the Average” measurement with recommendation to do that in power domain with a substantiation that it just would be nice and with research how many points is needed to get some accuracy level (because each point is expensive ...) is taking place.

Let’s add new level of accuracy by using a solution and tools already offered for 10 years...

Strange, but no one was offering me to take a look on results acquired by use of „internationally-standardized measurements” and much more – to compare that results with results gained from use of SPFR measurement. It’s never too late, let’s do that!

„... learned from disciplined, double-blind, listening tests.”

If it is possible to avoid any biasing for some researchers only by use of such tests (with respective budget). Ok, let them find such budgets and perform that.

As it was expressed in previous comment, the use of high skills and competence is most important for that than use of masses.

It is not so big a problem to hide the test object from the expert.

„ ... that it is sufficient to recognize the “melody”, the “rhythm” and “lyrics” of a song, and that the bandwidth, spectrum, linear- and non-linear distortions and sound levels do not alter the “art”. I beg to differ.” - understand

The “melody”, the “rhythm” and “lyrics” of a song are „properties” of a live performance. When such a performance is recorded to a carrying media it becomes an „image” of that live performance and will be a new object of art as it is in analogy with optical photography.

If such an image is artistic and rich, those properties will not be lost even by playback of such image (actually recording) by very low quality equipment.

If recording sounds well only on system with wide bandwidth and low distortions, it was badly recorded and the recording engineer was having fun from wide bandwidth and absence of distortions and does not understand the fact that his work has a low artistic value.

Engineers who know that, are placing some crap loudspeakers (narrow bandwidth, not even FR, non linear distortions) next to main monitors and switching to those from time to time to avoid becoming blind of „nice” sound of main monitors. It is needed less and less when enough experience and artistic skills are collected.

But, one very important aspect is that it’s possible only when main monitors not only have wide bandwidth and are free from non linear distortions but their FR is set to some very well equalized target – no sound coloring by monitors. Usually it is fall of 7 dB from LF to HF.

Otherwise, the engineer is fighting with monitoring problems and is loosing focus on his artistic work.

That is creating a curious fact for some engineers –the work created by use of ideally tuned monitors will sound good in any place with crap loudspeakers. The idea that engineer should use crap loudspeakers for his main work is completely wrong.

Same is with the idea that FR accuracy of +- 3 dB ( 400% error in power domain) is enough for monitoring. The accuracy of sound engineer’s decisions is in 1...2 dB (not 6) therefore the accuracy of +- 0.5 dB should be used. That lets the engineer to do his job (making decisions) even 2 times faster than usually ...

„At several points in his comments it is asserted that my focus is on consumer products, that “professional” loudspeakers are inherently superior.”

It would be nice if they would be somehow inherently superior. But we must make them superior by our respective attention. They are two completely different things – to listen for an enjoyment and to listen for a creative work.

„The best consumer loudspeakers and the best professional loudspeakers, as they measure and sound, are almost indistinguishable.”

- It is an injury against professionals.

„The flawed ones exhibit an infinite variety of misbehavior, not all of which are capable of “correction” after the fact. Identifying and correcting the flaws is made greatly more difficult if the only data comes from measurements in reflective spaces.”

- it takes a different approach but it is solved already.

„The listening ability of recording/mixing engineers was elaborately tested”

Looks like the 30 years old experiment was developed in a flawed way.

It was a listening test. It should have been a working test.

The ultimate accuracy of monitor speakers is showing its importance only in work process. The quick „listening to” by use of some unfamiliar program is not showing value of accurately tuned monitors instantly. The recording engineers usually report their impressions next day after they get new quality in their mixing room. Usually, as a sign of 2 times more effective working.

„In those tests, professional recording engineers and producers were mixed in with audiophiles as subjects in double-blind subjective evaluations of loudspeakers intended for use as broadcast/recording monitors.

As a result of noting that several of the professionals were unable to repeat their subjective ratings ... ”

- Why focus on „several who were unable”? There were several who were able, right?

Looks like to prove the idea that loudspeakers must serve requirements of 90% of public.

The requirements of professionals „who are able” are not important in such a case ...


„ ... shows how both professional and amateur listeners can be biased by visual information about the products”

I see Dr. Toole expression on blind test as most important to make any decisions.

I made a lot of test that should be named as blind. But most importantly, they were sufficient to me to keep working in this field and keep serving very critical demands of professional sound engineers and see their happiness. : )

It means, my tests were enough objective to not to make mistakes and to make future investments. It is possible to conduct any new tests to secure any investment right now.

Some examples of tests, collected in 10 years, which can not be called as not being blind.

1. Daughter is playing with dolls next room. I asked, let’s listen to music. But two versions - A and B. Did you here difference? -Yes I did! What kind of difference you hear? -The loudspeaker disappears in version B! How you can characterize version A? -Everything is too much ...

2. The loudspeaker manufacturer RRR is using Sound Power measurement (instead "on axes" measurement in anechoic chamber) for final tuning of their loudspeaker M1. They decided to participate in a contest conducted by magazine S. Magazine has chosen 7 brands (including RRR with their M1) for that contest. Results are published as broad report on 15 pages with measured curves included. The M1 gets second place but without any negative comment about it’s sound. Most important part of the comment on sound is "it is not understandable why it sounds so good". The speaker Y gets first place but with negative comment on its sound, being 2 times more expensive and 2 times heavier (biasing by sponsoring? : ) ). A lot of other participant’s curves are like drawn with a ruler. Curves of M1 are not such, therefore - not understandable for magazine’s experts.

3. Peter was making sound for an event. TV channel was making reportage from this event.

John is a competitor of Peter and is seeing and listening to that reportage. Then, when he meets Peter the first time, he says - it was a good idea to give TV a line signal from your mixing console. - No, TV was capturing everything by their camera mic, Peter answers.

4. Brant is a mixing engineer and serving his producer George abroad.

Brant decides to apply equalizing on his monitors J and is keeping working for George. Some time after that George is asking Brant - what is happening Brant, why your mixes get so good sound now?

5. Car audio competitions - judges are usually not biased by equipment installed on cars they are judging.

6. When rehearsal of an event was going on, some performers went down from stage, listened and turned to sound engineer asking - why FOH is not working!?! Only the MUTE of all FOH proved the opposite fact. That was happening many times.

Let’s offer to „standard committee” tools that are ready to use by ordinary technician not only for initial fine tuning but also for regular check because of high repeatability of such measurements and insensitivity to kind of operator’s behavior!

What about such experiment?

Let’s ask experts - how much sound coloring still remains in loudspeaker sound in comparison with live sound, instead of question – which speaker do you prefer?

Raimonds Skuruls 2015.26.11

Acoustic Power Lab
 
TheWarrior

TheWarrior

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#34
"I could go on, but all that I would say is either already in the literature, or awaits the results of the psychoacoustic investigations needed to fill in the few blanks left in the Journal paper that provoked these remarks. It is hoped that a new generation of peer-reviewed sound quality recommendation documents will emerge at some point. Then Mr. Skuruls may see the “real solutions” he desires – I was not being deliberately skimpy. In the meantime he has created his own solution, described on his website."

The one thing Floyd continuously states is the lack of standardization with in the recording industry, and until that time arrives, there will be no 'one size fits all' room eq solution that can function in every situation, without at least a few knobs to turn when the source changes.

And as someone trying to sell room eq, shouldn't YOU be the expert? Oops....
 
Bizarro_Stormy

Bizarro_Stormy

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#38
It seems as though Dr. Toole got his chocolate in Mr. Skuruls peanut butter...

or maybe it was the other way round...
 
Raimonds

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#39
Danley Sound Labs Inc.,Gainesville, GA, decided to use APL processing to relieve all beauty and nuances of their loudspeaker’s designs for a show at Prolight & Sound Frankfurt Musikmesse 2016. Come hear that in hall 3.1 (stand J81) and Concert Sound Arena.
 
Raimonds

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#40
Dear Friends,

Please take a look on Jack Regula`s paper:
https://soundforums.net/forum/pro-au...iew-of-apl-tda

And some announcement.

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