Does 'envelopment' exist? Can it be measured?

[Mort]

I hear trusted people use envelopment a lot. Can someone tell me what it is? How would I create more of it, assuming it's a good thing.

 

[tifune]

I hear trusted people use envelopment a lot. Can someone tell me what it is? How would I create more of it, assuming it's a good thing.

One perspective:

Genelec 8351B Review (Studio Monitor)

It's not particularly difficult to make them complain without hitting the limiters. Sub heavy content (hip hop, especially) even at reasonable levels will do it. If you need a good example, Hey Now on Kendrick Lamar's new album will do it. That's a speaker killer. Either speakers are faulty or...

www.audiosciencereview.com

 

[Jonas_h]

It is subjective if it is good or not. Some like the razor sharp headphone imaging and some like the big envelopment. (And I like a good mix of both)

But if you want more of it: Have wide dispersion speakers with smooth off axis response and dont put too much fuzzy absorbers on your walls.

Thats the simple answer.

 

[Sokel]

Best place to start:

Bass and subwoofers

This is the second in a series of follow-up posts to https://www.audiosciencereview.com/...-of-lokki-bech-toole-et-al.27540/#post-950580, this time focussing on bass perception with a brief digression on subwoofers, since there's relevance to (reproduction of) concert hall acoustics. I’ve...

www.audiosciencereview.com

 

[DVDdoug]

It can't be accurately measured or quantified. It's a perception or impression. Some aspects of it can be measured. It is common to measure the reverb time which relates to the proportion of direct sound from the speakers and reflected sound from all-around.

In a concert hall reflected sound comes from all directions. Perhaps more of the sound is indirect than direct. This is "good thing" because it's how classical music is intended to be performed and heard. Your brain can still detect the direction of the sound because the direct sound hits your ears first. IMO a lot of other music also sounds better in a large room with at least some natural reverb coming from all directions.

Surround systems can also envelope you, depending on the mix. When listening to regular stereo I like to use a "hall" or '"theater" setting on my AVR for some delayed reverb in the rear and the "feel" of a bigger space. In that case I'm NOT listening "accurately" or "as intended".

Most people like some reflections but some listeners prefer a "studio sound" with the sound coming from the front with a soundstage illusion coming from between the speakers.

 

[krabapple]

I hear trusted people use envelopment a lot. Can someone tell me what it is? How would I create more of it, assuming it's a good thing.

Envelopment is the sensation of being in a large space, arising from hearing delayed reflections of direct sounds.

Good concert hall acoustics naturally provide it. Multichannel 'surround' mixing and and/or reproduction is the best way to produce it at home.

(adapted from: Toole & Olive, Sound Reproduction, 4th ed)

 

[Mort]

Best place to start:

Bass and subwoofers

This is the second in a series of follow-up posts to https://www.audiosciencereview.com/...-of-lokki-bech-toole-et-al.27540/#post-950580, this time focussing on bass perception with a brief digression on subwoofers, since there's relevance to (reproduction of) concert hall acoustics. I’ve...

www.audiosciencereview.com

Lol I'm not reading that. Life is too short.

 

[Sokel]

Lol I'm not reading that. Life is too short.

That's the short version!



Seriously now, easily one of the best threads around.

 

[DWPress]

I prefer controlled diffusion over absorption at first reflections (except my ceiling) and use fairly shallow well diffusers targeting around 500-3kHz to make my16x20' room more ambient.

 

[Mort]

That's the short version!



Seriously now, easily one of the best threads around.

To you, it's bass that creates envelopment?

Most of the answers above were about reverberance, reflections and wide directivity.

There could be more than one use of the word.

 

[RickS]

Envelopment is discussed in Toole's writings. It has been discussed here, but not sure where. Would check the Luminary thread.

 

[dagfinn]

"To faithfully reproduce great acoustic recordings, a flattish frequency response of perceived-direct sound is just one of the goals. More importantly, to me, the monitoring room and sound system need to convey moving patterns of sound latent in the recording, especially between 40 and 200 Hz. This is where to hear the soul of a concert hall or church, in case it has been recorded.

Collapsing discrete channels to a single sub channel should therefore be a last resort, e.g. if the reproduction room/placement is difficult and/or to accommodate multiple listeners.

Taking advantage of discrete channel reproduction at low frequency has even spread outside acoustic recordings. Top pop/rock productions now also make use of such perceptual excitement, which will remain a secret to “collapsers” " @Thomas Lund in thread

Genelec GLM Review (Room EQ & Setup)

In a nutshell, since I do this for a living. You need EQ whether using one sub or multiple. Very difficult to get a flat response even with multiple subs. What you want is a response you can equalize, meaning no dips that can't be fixed with EQ. If you are mixing music for instance and you only...

www.audiosciencereview.com

 

[krabapple]

Envelopment is discussed in Toole's writings. It has been discussed here, but not sure where. Would check the Luminary thread.

The definition of envelopment I posted in this thread already is from Toole's book.

It's not (mainly) about bass and subwoofers.

 

[RickS]

"To faithfully reproduce great acoustic recordings, a flattish frequency response of perceived-direct sound is just one of the goals. More importantly, to me, the monitoring room and sound system need to convey moving patterns of sound latent in the recording, especially between 40 and 200 Hz. This is where to hear the soul of a concert hall or church, in case it has been recorded.

Collapsing discrete channels to a single sub channel should therefore be a last resort, e.g. if the reproduction room/placement is difficult and/or to accommodate multiple listeners.

Taking advantage of discrete channel reproduction at low frequency has even spread outside acoustic recordings. Top pop/rock productions now also make use of such perceptual excitement, which will remain a secret to “collapsers” " @Thomas Lund in thread

Genelec GLM Review (Room EQ & Setup)

In a nutshell, since I do this for a living. You need EQ whether using one sub or multiple. Very difficult to get a flat response even with multiple subs. What you want is a response you can equalize, meaning no dips that can't be fixed with EQ. If you are mixing music for instance and you only...

www.audiosciencereview.com

Yes, thanks for reminder, but it is Lund discussing as well as Toole. Is in several different threads.

 

[Sokel]

To you, it's bass that creates envelopment?

Most of the answers above were about reverberance, reflections and wide directivity.

There could be more than one use of the word.

AE described at the paper in the thread I posted is "Auditory Envelopment".

And as bass is responsible for the 30% of preference I would say is one of the strong aspects along with the spacial qualities, etc.

A lot more of research is needed probably, but clues are there.

 

[krabapple]

200Hz is well above most subwoofer use

AE described at the paper in the thread I posted is "Auditory Envelopment".

And as bass is responsible for the 30% of preference I would say is one of the strong aspects along with the spacial qualities, etc.

A lot more of research is needed probably, but clues are there.

There's a lot of papers cited in that 13-page thread.

Please link to the one you are referring to.

 

[Sokel]

200Hz is well above most subwoofer use

There's a lot of papers cited in that 13-page thread.

Please link to the one you are referring to.

Here's the direct link to it:

https://assets.swoogo.com/uploads/4646601-673c03ab61c93.pdf

 

[Duke]

Envelopment is the sensation of being in a large space, arising from hearing delayed reflections of direct sounds.

Good concert hall acoustics naturally provide it. Multichannel 'surround' mixing and and/or reproduction is the best way to produce it at home.

(adapted from: Toole & Olive, Sound Reproduction, 4th ed)

Well said.

Acoustician and psychoacoustician David Griesinger has an imo enlightening insight into the "how to" aspect. He's writing with concert halls in mind but this principle arguably applies to home audio as well:

"Envelopment is perceived when the ear and brain can detect TWO separate streams: A foreground stream of direct sound, and a background stream of reverberation. Both streams must be present if sound is perceived as enveloping."

Imo what is often missing in home audio is a sufficient time gap between the foreground stream (the direct sound) and the strong onset of the background stream (the reflections).

How would I create more of it

Imo, increase the time gap between the direct sound and the strong onset of (spectrally correct) reflections, and about ten milliseconds seems to be adequate.

In practice what often results is, a weakening of the "small room signature" of the playback room, and a stronger "sense of space" from the recording. In other words, this time gap in between the direct sound and the strong onset of reflections does more than just make your playback room sound a little bit bigger; in practice, it often allows the "sense of space" on the recording to become perceptually dominant, such that this "sense of space" changes appropriately and enjoyably from one recording to the next. In my opinion.

 

[krabapple]

Here's the direct link to it:

https://assets.swoogo.com/uploads/4646601-673c03ab61c93.pdf

'Auditory Envelopment' is a term Lund uses* in this white paper to describe a low frequency perceptual phenomenon he reports testing.
It has as 'narrower' definition than the 'listener envelopment' traditionally meant when the term 'envelopment' is used in audio, as he notes:

In this study, the term is used exclusively about the sensation elicited by low frequency interaural fluctuations in level and phase; an elementary, perceptual definition narrower than Listener Envelopment (LEV) in acoustical engineering [13]. In this context, absolute localization is not important, but low frequency inter-aural change is.

*whether he coined it himself, I can't say. Nor can I say whether this work, presented as a session talk at SMPTE's Media Summit of 2024, has been published/peer-reviewed. TL has been pushing the 'affective touch' hypothesis for awhile.

 

[Sokel]

*whether he coined it himself,.

Probably the case, but the effect is about just that, delivering more recorded "space" when present at the recording.
Sense of (recorded) 3D space is directly related with envelopment.