Studio Monitors & The Circle of Confusion- What We Know/Don’t Know

[boxerfan88]

Reference room - could be anything
Reference speakers - could be anything
Reference track - could be anything
Mix/mastering - could be anybody
Listener- could be anyone
CoC remains …



So, the discussion continues in a circle…

 

[witwald]

As the listener moves farther away from the speakers, the influence of the direct sound on perceived tonal balance decreases,

How is that the case? Isn't the main acoustic energy reaching the listener in a typical (good) listening room the direct radiation from the loudspeaker? Thus, wouldn't it hold most of the listening cues that we, the listeners, engage with? Looking below at the "+12%" seems to indicate that this is the case.

while the influence of the speaker’s sound power increases. In a listening position where the direct sound has no longer influence, perceived tonal balance is primarily determined by the sound power which is the total acoustic energy radiated by the loudspeaker in all directions. Since sound power reflects the speaker’s average response over all angles, it becomes the main factor shaping what the listener hears when reflections outweigh the direct sound.

Sean Olive’s predicted in-room response model is based on a weighted sum of three components

+12% sound power
+44% early reflections
+44% on-axis response.

This makes the estimated in-room response a representation of a farfield listening environment.

That seems to make sense and is consistent with my (limited) experience.

Not extremely farfield, but certainly beyond the nearfield.

A 3-metre listening distance for a home stereo system used for "quality" sound reproduction is not extremely farfield. This makes sense again.

For nearfield listening, we can assume that mostly the early reflection response and direct sound response matter the most.

Okay, I can see how that works: 1-metre listening distance and sound reflections from a desk are one example of such a situation. Cancellations at certain frequencies will clearly alter/color the perceived sound quality.

So, for such setups, the sound power response may be irrelevant.

So, it therefore seems that the overall sound power response is not so important for a large range of listening situations that are focused on subjective quality of sound reproduction.

Even if a speaker has a distorted or non-flat on-axis frequency response, it can still achieve a good overall sound power response as long as the diffractions in its directivity pattern are well controlled. Diffractions do affect sound power and on-axis response together but if they’re kept in check and don’t cause severe irregularities across angles, the total radiated energy can still sum to a smooth and balanced power response.

Can you provide an example of a commercial loudspeaker where this is the case? In my neck of the woods, nothing springs to mind. It's not entirely clear to me how a speaker with a "good" sound power response and a "bad" on-axis frequency response can sound subjectively "good" on a wide range of music material, while being listened to at a nominal 3-metre listening distance in a home listening environment.

 

[goat76]

Reference room - could be anything
Reference speakers - could be anything
Reference track - could be anything
Mix/mastering - could be anybody
Listener- could be anyone
CoC remains …



So, the discussion continues in a circle…

Let me ask you, don't you know of many music tracks, of different genres and styles, that you usually find sounding good on most audio systems you have heard them on, and especially good-sounding on the best audio systems you have had the chance to listen to?

Those are your reference tracks, and it's a pretty good chance that many other people will agree with you that those tracks sound good, and probably not that far from the tracks they would have chosen themself as reference tracks, in that same genre and style of music.

When an audio engineer works with his mix towards a reference track, there will not be much or any confusion for him about how that mix will sound on other audio systems where he has heard that reference track before, at least as long as he has reached the set goal of "copying" the overall balance of the reference track.


"The circle of confusion" is an exaggerated problem, mostly made to suit the explanation of a theoretical problem. In reality, most audio productions go through many speaker systems before they reach the consumers, and by comparing them to other audio productions, it is ensured that it doesn't fall too far off the grid.

 

[Blockader]

Without a definition the word “reference” is meaningless.

A Reference track is one you refer to.
Is a reference speaker one you refer to, to hear sound? That could literally be anything.

This is the problem. You insist that a “reference speaker” is a “need”, based purely on speculation. Not studies to indicate that’s the case.

Then you cannot give an indication of what that standard might even vaguely mean beyond “pretty good”.

You started talking like Jordan Peterson. but here's the thing:

The argument is self-defeating.

If we go by your reasoning, a reference track is just any track you choose to refer to. There’s no official certification that makes a track “reference”, it simply needs to be well-known, trusted, and consistent.

So if that definition works for tracks, why can’t the same logic apply to speakers?

A reference speaker can just as well be any known, trusted, and consistent speaker system with verifiable performance, for example, one with a neutral on-axis response, smooth off-axis behavior, and predictable sound power characteristics.

The word “reference” doesn’t imply perfection or some universal truth. It simply means a reliable point of comparison, a baseline you can return to when making critical decisions. That’s true whether you’re talking about tracks or monitors.

That’s why I brought up the IEEE 754 standard for 32-bit floating-point representation. It’s not flawless but because everyone uses it, we avoid getting lost in chaos and uncertainty. The same principle applies here.

This standard, however, wasn’t built purely on intuition or the subjective preferences of a few engineers: it was established for good reason, with solid technical merit behind it. That’s exactly why it’s time we move on from the NS10 as a so called standard too.

Because you’ve started making self defeating arguments, ones that don’t even apply to the things you’re defending but are used to undermine my points, I think it’s fair to say this conversation isn’t going anywhere productive. So, from this moment on, I’ll be ignoring your messages. Nothing personal about this from my side, I feel like you we are just wasting bits in ASR's servers.

 

[Blockader]

So, it therefore seems that the overall sound power response is not so important for a large range of listening situations that are focused on subjective quality of sound reproduction.

Iit’s worth noting that absorption and diffusion treatments which affect the sound power response can also influence the early reflection response, of course depending on the speaker’s directivity, the placement of the treatment, and room geometry.

Can you provide an example of a commercial loudspeaker where this is the case? In my neck of the woods, nothing springs to mind. It's not entirely clear to me how a speaker with a "good" sound power response and a "bad" on-axis frequency response can sound subjectively "good" on a wide range of music material, while being listened to at a nominal 3-metre listening distance in a home listening environment.

Only theoretically possible, that's why I did not want to discard the possibility. Few old Revel speakers come very close to being an example though.

 

[lowkeyoperations]

, it simply needs to be well-known, trusted, and consistent.

So if that definition works for tracks, why can’t the same logic apply to speakers?

Gosh. You know which speakers have been “well known, trusted and consistent” for decades now?

NS10

Bingo!

 

[Mart68]

Gosh. You know which speakers have been “well known, trusted and consistent” for decades now?


Bingo!

I can't recall if it was in an interview or in an article about NS10M that I read a while back now, but an engineer said that if he goes to work in a studio that doesn't have NS10M he takes his own set with him - so he has a known reference to work from.

 

[RickS]

The goal of giving this content its own thread was to allow a productive conversation on studio speakers to flourish. Clearly there is no single reference studio monitor, and this is part of what the circle of confusion calls out. Am going to put this quote from Dr. Olive at the start of the thread as well:

"As Toole points out, the key in breaking the circle of confusion lies in the hands of the professional audio industry where the art is created. A meaningful standard that defined the quality and calibration of the loudspeaker and room would improve the quality and consistency of recordings. The same standard could then be applied to the playback of the recording in the consumer’s home or automobile. Finally, consumers would be able to hear the music as the artist intended."

Posts here should either be about the current state of the production art and/or what can be done to improve it. Continuous quality improvement is a goal in most other production environments; sound production certainly has opportunities for improvement. Posts here should focus on this goal. Repeating one's opinion or attacking other's opinions does not help advance the cause here and those posts may be deleted and/or thread bans issued.

Please focus on objective facts and how standards or best practices can be applied to sound production. Thanks!

 

[RickS]

I can't recall if it was in an interview or in an article about NS10M that I read a while back now, but an engineer said that if he goes to work in a studio that doesn't have NS10M he takes his own set with him - so he has a known reference to work from.

While the NS10 is a good example of having a reference speaker. It is a flawed reference by contemporary standards AND is no longer sold.

Since the thread goal is how to improve the status quo, despite being "beloved", the NS10's only role here would be as a historic baseline.

 

[Mart68]

While the NS10 is a good example of having a reference speaker. It is a flawed reference by contemporary standards AND is no longer sold.

Since the thread goal is how to improve the status quo, despite being "beloved", the NS10's only role here would be as a historic baseline.

That it's the NS10 is irrelevant, it could be any loudspeaker of suitable size to be placed on the bridge, that the engineer is familiar with.

Since I take the position that there's not a problem here that needs fixing, I'll refrain from posting anything more on this thread.

 

[RickS]

That it's the NS10 is irrelevant, it could be any loudspeaker of suitable size to be placed on the bridge, that the engineer is familiar with.

Since I take the position that there's not a problem here that needs fixing, I'll refrain from posting anything more on this thread.

Your call ofc, but the question around using a given reference speaker is how the sound engineer might deal with potential flaws or differences due room conditions, etc. Am not suggesting there is any absolute, but the human factor remains.

If a sound engineer gets sick, hurt (or worse) in the middle of production, seems another engineer should be able to (hopefully) resume the effort with some consistency. Is that not a reasonable goal as opposed to discarding the original production effort?

 

[Blockader]

That it's the NS10 is irrelevant, it could be any loudspeaker of suitable size to be placed on the bridge, that the engineer is familiar with.

Since I take the position that there's not a problem here that needs fixing, I'll refrain from posting anything more on this thread.

What an engineer is familiar with is ultimately a local reference, one tied to their own hearing and cognitive biases. It serves as a reference only within that specific context and doesn’t necessarily provide any indication of whether it will help a mix translate well to other speaker systems or rooms.

Unless both listeners and engineers come together to build a shared consensus on how speakers should sound, translation issues will persist. Without that common ground, everyone is mixing and listening through slightly different lenses and the circle of confusion continues.

I agree that this problem might be less severe in 2025 than it was in 2001 or maybe not. What we need is unbiased research, with minimal limitations and conducted across multiple studies to properly determine whether that’s truly the case.

This is basically the summary of what I’ve been saying since the beginning.

My own experiences with my headphones and speakers have led me to notice that some recordings sound absolutely amazing from start to finish, while others consistently sound slightly off or even severely wrong. This wasn’t something tied to a single setup either I’ve used monitors like the KH 420, KH 310, KH 120A, briefly the ATC SCM20ASL and now the Genelec 8361 + W371 combo. This naturally gives me the bias to believe that the mixing engineer’s speakers or monitoring chain must have been vastly different from mine. If a song comes across as shouty from beginning to end, I tend to assume it’s not an artistic choice but rather a translation issue between their system and mine. Of course, this is anecdotal but I think it clearly explains where I’m coming from.

 

[Mart68]

Your call ofc, but the question around using a given reference speaker is how the sound engineer might deal with potential flaws or differences due room conditions, etc. Am not suggesting there is any absolute, but the human factor remains.

If a sound engineer gets sick, hurt (or worse) in the middle of production, seems another should be able to (hopefully) resume the effort with some consistency. Is that not a reasonable goal as opposed to discarding the original production effort?

There's at least a couple of professional engineers posting on this thread. I'll let them answer that if they so desire.

My experience is only as an observer watching recordings being made, and a fair amount of time studying the subject with a view to setting up a home studio.

All I can say is that at least some of the issues raised seem to stem from a lack of understanding as to how recordings are made. Also there is no point in concerning ourselves with this when the real issue is the poor quality of the replay systems, and their acoustic setting, of the end users.

That problem cannot be fixed except on an individual basis. So some end users will continue to complain about recording quality even if we created a rigid production standard that every studio adhered to.

 

[lowkeyoperations]

The goal of giving this content its own thread was to allow a productive conversation on studio speaker to flourish.

This thread is a good development as it means that the ATC thread isn’t constantly used for this purpose.

“A meaningful standard that defined the quality and calibration of the loudspeaker and room would improve the quality and consistency of recordings.”

Whilst posting Dr Olive quoting Toole is noteworthy, this quote is still only speculative.

It has not been studied to prove the thesis.

It should not be necessary for all forum members to take this speculation as gospel in order to participate in this thread!

Questioning this assumption should be allowed.

Since I take the position that there's not a problem here that needs fixing, I'll refrain from posting anything more on this thread.

The title of the thread is “Studio Monitors & The Circle of Confusion- What We Know/Don’t Know”

One thing we don’t know is that the Circle of Confusion even exists beyond theory!

There does not appear to be any general public sentiment that suggests consumers are unhappy that they cannot “hear the music as the artist intended." That sentiment appears to be limited to those who adhere to Toole’s speculation.

As Mart68 notes, there is no consensus that a problem exists.

 

[RickS]

There's at least a couple of professional engineers posting on this thread. I'll let them answer that if they so desire.

My experience is only as an observer watching recordings being made, and a fair amount of time studying the subject with a view to setting up a home studio.

All I can say is that at least some of the issues raised seem to stem from a lack of understanding as to how recordings are made. Also there is no point in concerning ourselves with this when the real issue is the poor quality of the replay systems, and their acoustic setting, of the end users.

That problem cannot be fixed except on an individual basis. So some end users will continue to complain about recording quality even if we created a rigid production standard that every studio adhered to.

Thanks for sharing your thoughts and I can see your points.

I think we are agreeing that there are no absolutes. Yes, that can be extended beyond just the production process as well. However, just because one part is imperfect, does not mean you simply give up on improving where improvement can be made.

 

[Palmer]

There's at least a couple of professional engineers posting on this thread. I'll let them answer that if they so desire.

My experience is only as an observer watching recordings being made, and a fair amount of time studying the subject with a view to setting up a home studio.

All I can say is that at least some of the issues raised seem to stem from a lack of understanding as to how recordings are made. Also there is no point in concerning ourselves with this when the real issue is the poor quality of the replay systems, and their acoustic setting, of the end users.

That problem cannot be fixed except on an individual basis. So some end users will continue to complain about recording quality even if we created a rigid production standard that every studio adhered to.

Even if we (?) created a rigid production standard... Good point. In a race, the racers run the race - not the spectators. Despite the standards, rules, team owners, and all the problems that are part of it. Some win, some lose, none of the racers ever say: if I only had the other guys car, I would have won. My experience.

 

[RickS]

This thread is a good development as it means that the ATC thread isn’t constantly used for this purpose.

Whilst posting Dr Olive quoting Toole is noteworthy, this quote is still only speculative.

It has not been studied to prove the thesis.

It should not be necessary for all forum members to take this speculation as gospel in order to participate in this thread!

Questioning this assumption should be allowed...

Your opinion has been noted more than once here. Please note the thread title and the Olive quote are guides and not absolutes. While can concede that some in the field may consider CoC overly presumptuous, does not mean there is no room for improvement. Will also concede that there may be one than one target listening device, but just because the problem is more challenging, is not an excuse to give up.

If you can show progress towards the goal of improving sound production process, carry on. Otherwise, can start your own thread.

 

[RickS]

The goal of giving this content its own thread was to allow a productive conversation on studio speaker to flourish. Clearly there is no single reference studio monitor, and this is part of what the circle of confusion calls out. Am going to put this quote from Dr. Olive at the start of the thread as well:

"As Toole points out, the key in breaking the circle of confusion lies in the hands of the professional audio industry where the art is created. A meaningful standard that defined the quality and calibration of the loudspeaker and room would improve the quality and consistency of recordings. The same standard could then be applied to the playback of the recording in the consumer’s home or automobile. Finally, consumers would be able to hear the music as the artist intended."

Posts here should either be about the current state of the production art and/or what can be done to improve it. Continuous quality improvement is a goal in most other production environments; sound production certainly has opportunities for improvement. Posts here should focus on this goal. Repeating one's opinion or attacking other's opinion does not help advance the cause here and those posts may be deleted and/or thread bans issued.

Please focus on objective facts and how standards or best practices can be applied to sound production. Thanks!

Given some posts after this one struggled to comprehend the above, here is some simpler guidance going forward:

Your posts can be about the problems (in sound production) but need to have a solution-oriented focus!

 

[Travis]

As an aside, I just pre-ordered the 4th Edition today, expanded content on Studios by @Floyd Toole and, as I understand it, a chapter related to headphones by @Sean Olive.

Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers, Rooms and Headphones (Audio Engineering Society Presents): Toole, Floyd E., Olive, Sean, Welti, Todd: 9781032761930: Amazon.com: Books

Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers, Rooms and Headphones (Audio Engineering Society Presents) [Toole, Floyd E., Olive, Sean, Welti, Todd] on Amazon.com. *FREE* shipping on qualifying offers. Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers...

www.amazon.com

 

[sigbergaudio]

As an aside, I just pre-ordered the 4th Edition today, expanded content on Studios by @Floyd Toole and, as I understand it, a chapter related to headphones by @Sean Olive.

Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers, Rooms and Headphones (Audio Engineering Society Presents): Toole, Floyd E., Olive, Sean, Welti, Todd: 9781032761930: Amazon.com: Books

Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers, Rooms and Headphones (Audio Engineering Society Presents) [Toole, Floyd E., Olive, Sean, Welti, Todd] on Amazon.com. *FREE* shipping on qualifying offers. Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers...

www.amazon.com

I tried to do the same, but the Kindle Edition isn't available in my region apparently. Hopefully that changes.