Relative importance of differences in stereo systems

[STC]

1 hour ago, esldude said:

things we can control on the playback end.

 

Exactly! Can you control the violin sound? You can’t. The level is more or less the same but the venue’s acoustics determine the performance SQ. 

 

The most common excuse during big audio show for poor performing state of the art speakers is the room. A reasonably a good pair of speakers can outperform  the  worlds best speakers placed in acousticly poor room. 

 

In the real world of orchestra musical performance, you hear 90% of the surrounding acoustics than the direct aound of the orchestra. That’s a fact. 

 

 

 

 

[esldude]

59 minutes ago, fas42 said:

Everyone knows tyres are the most important thing about cars - because they're the bits that make sure the car actually follows the road; they're so obviously, in your face, necessary! ... all one has to do is use the 'perfect' tyre, and any car will be a dream to drive ...

 

It's a good thing to keep in mind, that the obvious things are also the most important things.

False equivalency #2 in recent postings.  Everyone is doing great on this. 

[esldude]

10 minutes ago, STC said:

 

Exactly! Can you control the violin sound? You can’t. The level is more or less the same but the venue’s acoustics determine the performance SQ. 

 

The most common excuse during big audio show for poor performing state of the art speakers is the room. A reasonably a good pair of speakers can outperform  the  worlds best speakers placed in acousticly poor room. 

 

In the real world of orchestra musical performance, you hear 90% of the surrounding acoustics than the direct aound of the orchestra. That’s a fact. 

 

 

 

 

Your ideas seems to be shifting.  Why couldn't a good boombox outperform the real thing in an acoustically poor room?

 

My thinking was the same space will likely sound best for both the real sound and a recording over a boombox (though I can think of potential exceptions).  But a good floorstanding speaker will also be experienced the same.  And the floorstanding speaker will outperform the boombox in all spaces and come in second to the real thing in all spaces.  So the importance of the speaker quality is still there without disagreeing that the space can greatly alter the quality of the sound .

 

The video I posted illustrates how much differently spaces can sound.  However, that isn't how our hearing would have performed.  Our hearing would reject much of the reflected sound and hear primarily the direct sound.  So hearing thru to the source of the sound in various spaces is what our hearing does and it reduces the effect of the space (reduces not eliminates). 

 

In big spaces like orchestras in a large hall, 90% of the sound  reaching our ears is reflected, but even there our hearing reduces the perception to favor direct over reflected.  In a large enough space the difference is smaller, but still there.  

 

In any reasonably doable space for domestic listening, you can't make a boom box sound as good as a well done speaker.  And the place to improve the most is still the speaker.   Even if you disagree with this, I'd think you would agree to flip things and say speaker is second biggest issue.  Which simply moves the question of the OP toward, "speakers being one of the biggest remaining issues with quality sound, why isn't more time spent on fixing that problem?"

 

[STC]

16 minutes ago, esldude said:

Your ideas seems to be shifting.  Why couldn't a good boombox outperform the real thing in an acoustically poor room?

 

Let me rephrase that - "The most common excuse during big audio show for poor performing state of the art speakers is the room. A reasonably a good pair of speakers  in a good acoustics room can outperform  the  worlds best speakers placed in acoustically poor room.  "

 

 

Quote

 

My thinking was the same space will likely sound best for both the real sound and a recording over a boombox (though I can think of potential exceptions). 

 

No dispute there. 

 

Quote

 

But a good floorstanding speaker will also be experienced the same.  And the floorstanding speaker will outperform the boombox in all spaces and come in second to the real thing in all spaces.

 

Yes. No dispute when the room acoustics and the playback level is the same.

 

Quote

 

  So the importance of the speaker quality is still there without disagreeing that the space can greatly alter the quality of the sound .

 

Yes but the best speakers cannot perform better in a poor venue (acoustics wise) than a good speakers in a a good room.

 

Quote

 

The video I posted illustrates how much differently spaces can sound.  However, that isn't how our hearing would have performed.  Our hearing would reject much of the reflected sound and hear primarily the direct sound.  So hearing thru to the source of the sound in various spaces is what our hearing does and it reduces the effect of the space (reduces not eliminates).

 

IIRC, I was the first own who posted this video to illustrate how the surrounding acoustics can alter the direct sound. You are mixing up cocktail effect with precedence effect. 

 

Quote

 

In big spaces like orchestras in a large hall, 90% of the sound  reaching our ears is reflected, but even there our hearing reduces the perception to favor direct over reflected.  In a large enough space the difference is smaller, but still there. 

 

Again, you are mixing up with cocktail effect. Toole's research on lateral reflection will show how important is the delayed reverberation to increase the spaciousness of a performance.

 

Quote

 Even if you disagree with this, I'd think you would agree to flip things and say speaker is second biggest issue.

 

Speaker is second. Yes. 

[esldude]

7 minutes ago, STC said:

 

Let me rephrase that - "The most common excuse during big audio show for poor performing state of the art speakers is the room. A reasonably a good pair of speakers  in a good acoustics room can outperform  the  worlds best speakers placed in acoustically poor room.  "

 

 

 

No dispute there. 

 

 

Yes. No dispute when the room acoustics and the playback level is the same.

 

 

Yes but the best speakers cannot perform better in a poor venue (acoustics wise) than a good speakers in a a good room.

 

 

IIRC, I was the first own who posted this video to illustrate how the surrounding acoustics can alter the direct sound. You are mixing up cocktail effect with precedence effect. 

 

 

Again, you are mixing up with cocktail effect. Toole's research on lateral reflection will show how important is the delayed reverberation to increase the spaciousness of a performance.

 

 

Speaker is second. Yes. 

No not mixing up cocktail effect with precedence.

 

An example, posted here somewhere, is where I recorded music at my LP from speakers.  And from very close to the speakers.  The LP position sounds nothing like how it sounds.  Everything sounds too distant and almost echoey.  Because the recording picks up the direct sound and reflections.  Our hearing ignores some few milliseconds of the reflections, but can't do that if the reflections are in the original recording.  Enough in a small space that much of the room reflection is ignored.  Toole shows that for reflections arriving long enough after the sense of space is effected.  In most domestic situations that effect isn't zero, but it isn't much.   The up close recording gets rather close to how it sounded at the LP because it is much more direct sound and much lower level for reflected sound. 

 

Again whether you agree or not all speakers have enough imperfections they all sound different.   Much more obviously than all other parts of the reproduction chain prior to the speaker excepting intentionally broken designs.  Improving that will improve the results in good rooms and poor rooms.  

[STC]

11 minutes ago, esldude said:

No not mixing up cocktail effect with precedence.

 

An example, posted here somewhere, is where I recorded music at my LP from speakers.  And from very close to the speakers.  The LP position sounds nothing like how it sounds.  Everything sounds too distant and almost echoey.  Because the recording picks up the direct sound and reflections.  Our hearing ignores some few milliseconds of the reflections, but can't do that if the reflections are in the original recording.  Enough in a small space that much of the room reflection is ignored.  Toole shows that for reflections arriving long enough after the sense of space is effected.  In most domestic situations that effect isn't zero, but it isn't much.   The up close recording gets rather close to how it sounded at the LP because it is much more direct sound and much lower level for reflected sound. 

 

You got the principle right but the application to your example is incorrect. Most of  delayed sound should originates from a different direction. Only a small amount of reverberation that originates from the frontal stage should be in the recording. If you were to record at LP then all the reverbs will originate from the same source as the direct sound. The brain will now consider them as first event which affects the clarity. Even those using binaural dummy head do not record them at LP but much closer to the performance.

 

It is incorrect to say the brain ignoring the reflection from the room, it receives and process them differently as compared to to the same sound played through the loudspeakers.

 

 

[fas42]

Something that might cheer up the day of a few people ... of course, this bears no relevance to any people on AS,

 

https://bigthink.com/errors-we-live-by/why-some-of-our-best-minds-speak-higher-twaddle

[esldude]

1 hour ago, STC said:

 

You got the principle right but the application to your example is incorrect. Most of  delayed sound should originates from a different direction. Only a small amount of reverberation that originates from the frontal stage should be in the recording. If you were to record at LP then all the reverbs will originate from the same source as the direct sound. The brain will now consider them as first event which affects the clarity. Even those using binaural dummy head do not record them at LP but much closer to the performance.

 

It is incorrect to say the brain ignoring the reflection from the room, it receives and process them differently as compared to to the same sound played through the loudspeakers.

 

 

That is what I was saying.  The delayed sound from speaker in room comes from another direction and delayed so your hearing processes it differently.  You can uncover that by recording with a microphone so that all those reflections come from the speaker as a direct sound.  So you are hearing the part your hearing has ways of listening past and ignoring. The early reflections, and the early reflections are a result of the room.  But those are largely not noticed by you compared to the level at which they really exist. 

[STC]

32 minutes ago, esldude said:

That is what I was saying.  The delayed sound from speaker in room comes from another direction and delayed so your hearing processes it differently.

 

It is processing exactly how it supposed to process.

32 minutes ago, esldude said:

 

 

  You can uncover that by recording with a microphone so that all those reflections come from the speaker as a direct sound.  So you are hearing the part your hearing has ways of listening past and ignoring.

 

If you are insisting the brain is ignoring then you are saying it is cocktail effect. reverberation and localization fall in delays category.

32 minutes ago, esldude said:

 

The early reflections, and the early reflections are a result of the room.  But those are largely not noticed by you compared to the level at which they really exist. 

 

I do not understand. In any case, whatever you record will sound awful in a reflection free room. In your room, the room reflection colors the sound from the speakers, that is the recorded sound. How good or bad the coloration depends on the quality of the room reverberation. If you are listening to a typical audiophile vocal recording then the average room with 0.4 to 0.6s RT can sound very good indeed but to have classical recording to sound as in a concert hall then you need to have a reverberation of about 1.7s RT which physically not possible with a typical room dimension.

 

Let's start over. What are we arguing about?

[eternaloptimist]

For me the biggest factors are: speakers, room and DAC in that order....

Changes in pre and power amps were more subtle, although I wasn't starting with crap...

 

[Blackmorec]

Esldude and STC.....couple of points to aid your discussions

1. The brain does not ignore early reflected sound. It ignores the early time delay. So in a room with a lot of early reflections you will hear ‘louder and more intense’ sound.

2. Audiophile vocal vs. Classical recordings.... the same optimised listening room should work perfectly for both. You don’t want your listening room to add reverb. What you want is for your listening room to reproduce the reverb that’s on the recording, not add more. 

For a violin to sound like it does in a concert hall it should ideally be played in a venue with a long RT. For the recording of a violin played in a concert hall to sound like its in a concert hall a listening room with an optimised RT of 0.2 to 0.6s is what’s required, given that you want to reproduce the reverb on the recording and not add reverb, which would be incorrect. 

[STC]

21 minutes ago, Blackmorec said:

Esldude and STC.....couple of points to aid your discussions

1. The brain does not ignore early reflected sound. It ignores the early time delay. So in a room with a lot of early reflections you will hear ‘louder and more intense’ sound.

 

Blackmorec, thank you for your input, but my understanding is different. The brain processes all delays which are crucial for localization. Perhaps delays below 22 microseconds are the ones that brain couldn't detect. Reference Blauert.

 

21 minutes ago, Blackmorec said:

 

2. Audiophile vocal vs. Classical recordings.... the same optimised listening room should work perfectly for both. You don’t want your listening room to add reverb.

 

That depends. I use 22 speakers spaced in the configuration of a circle ( using time delay). I control the reverbs by using at least 48 individual impulse response of an actual concert hall which can be anywhere from 0.4 to 3.3s without echoes or other usual problem that you may have in a real room with long reverberation.  

 

My rooms original RT was 0.28s. I have modified the RT by adding diffusers over the absorbers and increased it to 0.4s. Unlike, the reverberation of the room the concert hall's IRs are smooth and the decay is a gentle slope which is hard to get in a typical room. 

 

With audiophiles vocals, they are at low RT value and good classical it can be at almost 1 to 1 ratio. Not my room's reverberation but a concert hall's reverberation. Reverberation is crucial for the feel of the ambiance. No one number fits all but thanks to today's technology now it is possible to do that with a single click of the mouse.

 

21 minutes ago, Blackmorec said:

 

What you want is for your listening room to reproduce the reverb that’s on the recording, not add more.

 

 

A room cannot selectively reproduce the reverberation. It reproduces whatever sound that comes out of the loudspeakers reverbs plus direct sound. The actual amount of reverbs in the recordings usually around 0.3 or 0.4s long.

 

 

21 minutes ago, Blackmorec said:

 

 

For a violin to sound like it does in a concert hall it should ideally be played in a venue with a long RT. For the recording of a violin played in a concert hall to sound like its in a concert hall a listening room with an optimised RT of 0.2 to 0.6s is what’s required, given that you want to reproduce the reverb on the recording and not add reverb, which would be incorrect. 

 

This is correct but for a different reason. It is impossible to have a long RT in a small room. It cannot occur naturally and a concert hall reverberation is unique which the architecture of your room will not allow that to happen.

 

If you are speaking from your knowledge as someone involved in recording than it is correct. But this is about playback of a recording. A better understanding of this will be playing a violin recording in a concert hall and listen how good it sounds. AR 1960 live vs recorded demonstrated that it was hard to distinguish a real and recorded performance in a concert hall. The concert hall own reverberation would have overwhelmed the recording 's reverberation, but that did not happen because no recordings meant for playback over the speakers contained reverberation other than the frontal stage which is also at a low level as close miking would have avoided most of them. Even if you use the critical radius for the mic placement that will be about 1/3 or 1/2 of the 1.1 ratio distance so still not even half of what a listener hears at his LP.

[John Dyson]

11 hours ago, fas42 said:

 

You are not right, at least for part of the population - there is a standard of SQ which triggers the brain into experiencing a convincing auditory illusion; if you haven't personally come across this, it may be because A) your brain is not wired for allowing it, or B) the standard of playback has never been good enough.

I still don't think that you understand -- you are missing details if you think that SQ works very well.  It works adequately well for some people who haven't learned to discern.  SQ is a fairly cheap replacement for accuracy...  That is okay...  There huge messes in the differnece between SQ/QS and friends vs. the actual signal & human hearing.

If someone's hearing cannot discern -- then the limitation is in their hearing.

 

John

[Blackmorec]

3 hours ago, STC said:

 

Blackmorec, thank you for your input, but my understanding is different. The brain processes all delays which are crucial for localization. Perhaps delays below 22 microseconds are the ones that brain couldn't detect. Reference Blauert.

 

 

That depends. I use 22 speakers spaced in the configuration of a circle ( using time delay). I control the reverbs by using at least 48 individual impulse response of an actual concert hall which can be anywhere from 0.4 to 3.3s without echoes or other usual problem that you may have in a real room with long reverberation.  

 

My rooms original RT was 0.28s. I have modified the RT by adding diffusers over the absorbers and increased it to 0.4s. Unlike, the reverberation of the room the concert hall's IRs are smooth and the decay is a gentle slope which is hard to get in a typical room. 

 

With audiophiles vocals, they are at low RT value and good classical it can be at almost 1 to 1 ratio. Not my room's reverberation but a concert hall's reverberation. Reverberation is crucial for the feel of the ambiance. No one number fits all but thanks to today's technology now it is possible to do that with a single click of the mouse.

 

 

 

A room cannot selectively reproduce the reverberation. It reproduces whatever sound that comes out of the loudspeakers reverbs plus direct sound. The actual amount of reverbs in the recordings usually around 0.3 or 0.4s long.

 

 

 

This is correct but for a different reason. It is impossible to have a long RT in a small room. It cannot occur naturally and a concert hall reverberation is unique which the architecture of your room will not allow that to happen.

 

If you are speaking from your knowledge as someone involved in recording than it is correct. But this is about playback of a recording. A better understanding of this will be playing a violin recording in a concert hall and listen how good it sounds. AR 1960 live vs recorded demonstrated that it was hard to distinguish a real and recorded performance in a concert hall. The concert hall own reverberation would have overwhelmed the recording 's reverberation, but that did not happen because no recordings meant for playback over the speakers contained reverberation other than the frontal stage which is also at a low level as close miking would have avoided most of them. Even if you use the critical radius for the mic placement that will be about 1/3 or 1/2 of the 1.1 ratio distance so still not even half of what a listener hears at his LP.

 

Delays which are crucial to localisation are not the same as delays due to early and late reflections.  Delays crucial to localisation  are essentially those caused by the different distance between the sound source and our 2 ears, whereas delays that cause reverberation are caused by sound bouncing off reflective surfaces in the listening venue. They are not handled the same way by human hearing so you can’t discuss them exchangeably.

The human ear receives a soundwave at each ear. Due to the distance between our ears there will be a delay to one of the waves, plus a small drop in amplitude and a shift in phase. The brain locks onto that delay, amplitude and phase shift to assign location. Similar waves reaching the ear from nearby reflections are summed with the original wave and the original location is preserved.  So again, for reflections with very short delays the amplitude is added to the original and the delay is ignored. Reflections with longer delays are given their own location and are heard as echoes or reverberation.  

Essentially what the brain is doing is 

1. Identifying the location of the original sound without getting confused by nearby reflections. Very useful for survival, where unambiguous location is paramount

2. Using later delays to estimate the proximity of reflecting surfaces like walls and ceilings. Human beings are very sensitive to the ratio of loss and amplitude and delay. Bats several orders of magnitude more so. 

[STC]

47 minutes ago, Blackmorec said:

 

Delays which are crucial to localisation are not the same as delays due to early and late reflections.  Delays crucial to localisation  are essentially those caused by the different distance between the sound source and our 2 ears, whereas delays that cause reverberation are caused by sound bouncing off reflective surfaces in the listening venue. They are not handled the same way by human hearing so you can’t discuss them exchangeably.

 

This is actually very relevant. Human localize sound among others by the timing difference between the two ears. That is limited to about 700µs depending on the ears spacing. When the reverberation is recorded it is still localized by the same location as the timing difference between the ears are still the same. 

 

The reflection from the room comes from other directions around you. This sound when it is within 1ms to 30ms is not perceived to come from a distinct location but fused together with the initial sound. The timing is only relevant if only a single short pulse is used. In complex sound like music, the difference can extend a couple of hundred ms without being perceived as a separate event. The ideal level is said to be 80ms for the late reflection for orchestra music in concert hall.

 

I agree they are not handled in the same way but when it comes from the speakers they are interpreted as how the original sound is heard. We are actually talking the same thing but the only point that needs some clarification is your statement that is " So again, for reflections with very short delays the amplitude is added to the original, and the delay is ignored." Do you have a specific number as to how short is the delay?

 

Quote

The human ear receives a soundwave at each ear. Due to the distance between our ears there will be a delay to one of the waves, plus a small drop in amplitude and a shift in phase. The brain locks onto that delay, amplitude and phase shift to assign location. Similar waves reaching the ear from nearby reflections are summed with the original wave and the original location is preserved.  So again, for reflections with very short delays the amplitude is added to the original and the delay is ignored. Reflections with longer delays are given their own location and are heard as echoes or reverberation.  

 

This is going OT so it is best we move to a new thread.

[STC]

1 hour ago, John Dyson said:

SQ is a fairly cheap replacement for accuracy.

 

It depends on which parameter's accuracy you are referring to. 

[Blackmorec]

2 hours ago, STC said:

 

This is actually very relevant. Human localize sound among others by the timing difference between the two ears. That is limited to about 700µs depending on the ears spacing. When the reverberation is recorded it is still localized by the same location as the timing difference between the ears are still the same. 

 

The reflection from the room comes from other directions around you. This sound when it is within 1ms to 30ms is not perceived to come from a distinct location but fused together with the initial sound. The timing is only relevant if only a single short pulse is used. In complex sound like music, the difference can extend a couple of hundred ms without being perceived as a separate event. The ideal level is said to be 80ms for the late reflection for orchestra music in concert hall.

 

I agree they are not handled in the same way but when it comes from the speakers they are interpreted as how the original sound is heard. We are actually talking the same thing but the only point that needs some clarification is your statement that is " So again, for reflections with very short delays the amplitude is added to the original, and the delay is ignored." Do you have a specific number as to how short is the delay?

 

 

This is going OT so it is best we move to a new thread.

Yes, the number is mentioned in the definition of the Precedence Effect (Law of First Wavefront).

For clicks its 1-5ms but for more complex sounds it can go up to 40ms. 

If anyone’s interested they could Google and read the Wiki blurb 

Interesting discussion but you’re right it is going OTT😉

[fas42]

8 hours ago, John Dyson said:

I still don't think that you understand -- you are missing details if you think that SQ works very well.  It works adequately well for some people who haven't learned to discern.  SQ is a fairly cheap replacement for accuracy...  That is okay...  There huge messes in the differnece between SQ/QS and friends vs. the actual signal & human hearing.

If someone's hearing cannot discern -- then the limitation is in their hearing.

 

John

 

Okay. Big misunderstanding - in audio forum land SQ means Sound Quality, not a 4 channel encoding mechanism.

[John Dyson]

On 1/19/2019 at 9:32 AM, STC said:

 

It depends on which parameter's accuracy you are referring to. 

I am speaking both of the listening experience being an inaccurate representation of true quad, and also electronically it is very very far off from the painstakingly created multichannel material.

If the artist/engineer PLANS for the limitations of SQ, it might be convincing, but it still wont be accurate WRT the quad recorded for mastering.

Don't get me wrong -- SQ can sound nice -- I am not talking about 'sounding nice.'   The big problem with 'sounding nice' is that it is very subjective...  For example, there are some people who really like compressed sound -- and considering the artists intentions when using compression, then that is their choice.  However, certainly much much of the time, a compressor (esp limiter) will create very large amounts of IMD when compared with the best of linear/non-processing equipment.  Much IMD is not due to the quality of the gain control elements or the quality of 'capacitors' -- it is minimally due to the math/physics of gain control (esp fast/hard gain control.)

Point being -- 'beauty is in the eye/ear of the beholder.'   Much of the time, I can hear the IMD from compression  (DBX is a little better, but a lot of FET compressors splat all over the place, it is just that people have become used to it.  Optos help the problem in a similar fashion as DBX), so even though compression usually distorts the sound, and distracts me -- alot of people do like the  fullness (sometimes intensity) of the sound.

Point being -- if you say that something sounds accurate -- well, to you it might -- just as someone whose native language is different than mine, I might not notice sounds that he/she does and vice versa.

Absolutes in the subjectiive/perception area are seldom possible to accurately claim, however absurd statements can be filtered out as 'misguided opinion.'   Note that I seldom advocate, by my position is to observe and apply some science and physics to the situation.)  (Science & physics include perception issues.)

I am all for an audiophile hobby -- but I disagree with making strong subjective claims as fact unless it is clearly implied as 'IMO.'  Even IMNSHO is okay.  A lot of people are NH esp in their field of interest/love of hobby.

[STC]

@John Dyson sorry for the misunderstanding. I was referring to sound quality not stereo quadraphonics. Although, IMO Quad can sound better than stereo when implemented right. 

[John Dyson]

23 minutes ago, STC said:

@John Dyson sorry for the misunderstanding. I was referring to sound quality not stereo quadraphonics. Although, IMO Quad can sound better than stereo when implemented right. 

Well -- sometimes (many times) some kind of multi-channel thing can sound impressive.  Sometimes (one in a million) might come close to spatially accurate (at one location in the listening venue as recorded in the studio or hall.)  IMO, this is another case of 'sounding good.'

Maybe a scheme where a head with the same geometry as the listener, microphones in each ear, then headphones on the playback -- that might come close to realism.  However, there are still issues with the frequency response variations of the microphone (pretty well controlled) and the coupling of the headphones to the listener (usually not so accurate, but sounds good.)

Then, then 'head' can be moved around to emulate the location in the studio/hall. :-).  Creating a listening environment where moving around is identical to the recording studio/concert hall isn't likely (but might come close for some people and/or limited movement.)

 

Still, that is 'sounds good'.  My interest tends towards the electronics part of the whole thing, and except for NR damage & tape noise that the NR tries to remedy (of course, on old material), that stuff is close to perfect.  Maybe in the early 1980s, there were still problems, amplfiers  but nowadays with power transistors with fT in the tens of MHz, almost all amplification issues have now been resolved.

The ubiquitous U47/U87 and other colorful microphones, and using a DolbyA for vocal enhancemnt -- those were bad also, but an artistic choice.  Of course, back in the '70s, I was using Condenser/FET microphones totally flat in the audio range, so perfection in some areas back then was nearly possible -- but not always used or desirable.  Using 'colorful' microphones doesn't bode well for realism either.

 

Point being -- perfection (or nearly so) has been available when it comes to everything but transducers and listening environment-- it is just a matter of practicality and taste.

[Kal Rubinson]

2 hours ago, John Dyson said:

NR damage

And that means.............................

[Ralf11]

Nose Reduction

 

(you're in NYC - surely you know that...)

[Axial]

NR damage, as in tape decks with A, B, C, S Dolby. ...Filters for the music, adding a veil to disguise the impurities, adding coloring to mask the rain falling down the sky (wow, flutter and jitter). 

 

I think it was in that meaning direction ...

[fas42]

4 minutes ago, Ralf11 said:

Nose Reduction

 

(you're in NYC - surely you know that...)

 

If you happen to be Michael Jackson, it certainly is a concern ...