Does 'envelopment' exist? Can it be measured?

[AporeticX]

Fairly new here, and maybe I'm being misled by the sub-forum heading, but most of the discussion seems centered on speakers, room acoustics, and psychoacoustics. Do amplifiers and/or DACs play a role in envelopment? Is "soundstage" (a seemingly equally nebulous term) related and/or measurable?

 

[john61ct]

> amplifiers and/or DACs

if they are good, straight-wire pass through

If crappy, they will have a negative impact across the board.

Soundstage is psychoacoustics

 

[Hindsider85]

I had the D5 Pro for 3 years. Its a chinese clone of the Dartzeel NHB-108 Two.
I dont care what anybody says, but its sound was different to any AMP I have ever listened to. It does something that lets the sound linger in the air. It has an ethereal character to it. One that you wont get from any other device or brand.
Maybe I will own a real Dartzeel AMP, one day...

 

[Ropeburn]

I had the D5 Pro for 3 years. Its a chinese clone of the Dartzeel NHB-108 Two.
I dont care what anybody says, but its sound was different to any AMP I have ever listened to. It does something that lets the sound linger in the air. It has an etherial character to it. One that you wont get from any other device or brand.
Maybe I will own a real Dartzeel AMP, one day...

These are vague terms and not something I'd expect from an amplifier. "No other amp" suggests it must be technically worse. The interesting part begins when you start to analyse where that impression comes from. Could be many things really, including your brain. It's always good to start investigating. However, "lingering" and "ethereal" is something I associate with music and sound design, for a example a "heavenly" choir or similar sounds, not a playback device.

 

[Hindsider85]

These are vague terms and not something I'd expect from an amplifier. "No other amp" suggests it must be technically worse. The interesting part begins when you start to analyse where that impression comes from. Could be many things really, including your brain. It's always good to start investigating. However, "lingering" and "ethereal" is something I associate with music and sound design, for a example a "heavenly" choir or similar sounds, not a playback device.

Well I never said its reproduction is faithful to the source. Im sure a Topping B200 will measure MUCH better than any Dartzeel AMP. But I can also assure you I would NEVER pick a Topping Class D over a Dartzeel AMP. And not because of its price and luxury or anything like that. And I only had the chinese clone. Im sure the real deal is still better. I've read in some forum, a year or two ago, of someone who had a real Dartzeel and the D9 Pro, which is a slightly refined D5 Pro. That person said the clone reached about 70% of the real Dartzeels performance and that he was impressed. Now what "70% of a real Dartzeel" means is up to your own imagination.

 

[Ropeburn]

Well I never said its reproduction is faithful to the source. Im sure a Topping B200 will measure MUCH better than any Dartzeel AMP. But I can also assure you I would NEVER pick a Topping Class D over a Dartzeel AMP. And not because of its price and luxury or anything like that. And I only had the chinese clone. Im sure the real deal is still better. I've read in some forum, a year or two ago, of someone who had a real Dartzeel and the D9 Pro, which is a slightly refined D5 Pro. That person said the clone reached about 70% of the real Dartzeels performance and that he was impressed. Now what "70% of a real Dartzeel" means is up to your own imagination.

Any deviation from transparency is by definition a technical imperfection. However, what I meant by the interesting part and analysing, if you find the technical reasons for that deviation and what exactly it is technically, and you happen to like that (given it's positively audible, rather easy to test, if a bit laborious), then you'll have a much easier time to get that elsewhere, or even recreate it artificially. Because now you know what you're looking for.

The big advantage of that in general is that you're not limited to the single device for that sound character anymore. If you manage to simulate it sufficiently, it's also adjustable, usable on many more devices, and defeatable. Many choices are better than one.

 

[john61ct]

Why put amp in all caps?

 

[dagfinn]

Mixing for vinyl, otherwise needle can jump out of the groove.

Club/DJ Mixes, to prevent phase issues across multiple speakers

EDM Techno/ House etc sub-bass and kick drum usually mono'd , Hip-Hop as well

Also in many mainstream pop / rock, very low sub-frequencies gets mono'd to remain in the center (synth oscillator) but keeping a separate stereo layer (even if slight), for the higher harmonics and midbass to give a wider feel in headphones.

What vinyl mix? What club mix, EDM, pop - ? Name a track, show an FFT. Shouldn't be hard for you, if it is common.

Besides, it seems you don't understand the difference of a centered bass or drum vs summed to mono. That's two completely different things.

 

[dagfinn]

You are correct, there is a lot of music with a mono bass out there for different reasons. But when I analyzed many tracks from all types of music genres a couple of years ago, I was really surprised to find that most of them actually contained stereo information all the way to the deepest bass. Some of the tracks had large deviations in the bass between the left and right channels.

It's a problem when people can't discern a centered/mono instrument from a summed low end. Like you say, most tracks are stereo all the way.
I'm still looking for a summed track, but haven't found one.

 

[dagfinn]

Here's an analysis done by iZotrope - for engineers, mostly, but it's quite understandable for everyone.

He goes through origins, purposes, pros and cons - and analyzes some sources. Envelopment is also touched on. Izotrope is a software company, so he uses iZotrope tools. I have none of those, and no affiliation.

 

[Sokel]

I'm still looking for a summed track, but haven't found one.

We have one:

Bass and subwoofers

The reason I want to test the method against a vinyl rip is to check that the method works for identifying decorrelated bass frequencies. What I want to see is nulled out bass

www.audiosciencereview.com

(the second row of Deltawave'd charts)

But it's mono, all the way, through and through

 

[dagfinn]

We have one:

Bass and subwoofers

The reason I want to test the method against a vinyl rip is to check that the method works for identifying decorrelated bass frequencies. What I want to see is nulled out bass

www.audiosciencereview.com

(the second row of Deltawave'd charts)

But it's mono, all the way, through and through

Mono all the way is something else, like you know. Have a look at the Izotrope video .

Btw, this thread belongs somewhere else, it has nothing to do with amps.

 

[Sokel]

it has nothing to do with amps.

???
Amps? Where did that came from?

We're talking about the recordings, only.

Edit: Oh, I see. there's a conversation in between. Totally off topic.

 

[dagfinn]

???
Amps? Where did that came from?

We're talking about the recordings, only.

Edit: Oh, I see. there's a conversation in between. Totally off topic.

This is the "Stereo and Multichannel Amplifier Reviews" subforum, it should perhaps be in more suitable subforum? @RickS

 

[thcdru2k]

The iZotope video shows that almost all modern mixes aren’t strictly mono in the low end anymore. There’s still meaningful stereo information in the 40–100 Hz range in many tracks.

In my setup I run dual subs under my bookshelves with physically aligned baffles. I manually calibrate for summation through the crossover and minimal spectral decay. I use a weighted crossfeed matrix via a miniDSP Flex HTx so each sub gets its own channel as dominant plus a reduced amount of the opposite channel. It’s not true stereo bass and not pure mono.

The Flex HTx just makes this practical because it allows precise control of routing, delay, and levels in one place.

The goal isn’t to force stereo bass, it’s to preserve some of the spatial structure already in the recording while maintaining clean summation and decay through the crossover. Mono is still the safer default if timing, placement, and level control aren’t dialed in. I have a preset where I disable my crossfeed (another benefit of Flex HTx). I find myself not using that preset so much. I benefit from a large open concept room where decay and room modes are less dominant.

 

[Thomas Lund]

But is that sacrifice worth it? And those studies are in anechoic chambers or in the free-field. Are they applicable in listening rooms?

We should start with what humans are actually able to hear and appreciate. Auditory Enveloplemt (AEV) is not voodoo, like elevating cables from the floor; or adding fringe precision, like high sample rates. AEV just works its sensory miracles over the five lowest audible octaves, for all to hear.

Mono bass “management” takes away the two lowest, and the living room one more. The combination of reproduction system and a (benign) listening room therefore acts like an FM radio processor, always serving a bland middle-of-the-road result.

It is measurable in the source signal, and it is measurable in room, if you manage to recreate it...

...there is a lot of music with a mono bass out there for different reasons. But when I analyzed many tracks from all types of music genres a couple of years ago, I was really surprised to find that most of them actually contained stereo information all the way to the deepest bass...

Thanks to big, flush-mount monitors, recording artists have been able to hear AEV for 70 years now. Listen to even the earliest Bruce Swedien recordings of Count Basie, Oscar Peterson etc. Bruce heard it, or he wouldn’t have been able to preserve AEV so faithfully.

There has been an unbroken chain of very careful audio professionals ever since.

If I may, recreational listeners underestimate the importance of conveying inter-aural fluctuation latent in a recording, without being distorted beyond recognition. Most of the emotion-modulation potential of sound (not of music) is lost, right there.

 

[audiofooled]

We should start with what humans are actually able to hear and appreciate. Auditory Enveloplemt (AEV) is not voodoo, like elevating cables from the floor; or adding fringe precision, like high sample rates. AEV just works its sensory miracles over the five lowest audible octaves, for all to hear.

Mono bass “management” takes away the two lowest, and the living room one more. The combination of reproduction system and a (benign) listening room therefore acts like an FM radio processor, always serving a bland middle-of-the-road result.



Thanks to big, flush-mount monitors, recording artists have been able to hear AEV for 70 years now. Listen to even the earliest Bruce Swedien recordings of Count Basie, Oscar Peterson etc. Bruce heard it, or he wouldn’t have been able to preserve AEV so faithfully.

There has been an unbroken chain of very careful audio professionals ever since.

If I may, recreational listeners underestimate the importance of conveying inter-aural fluctuation latent in a recording, without being distorted beyond recognition. Most of the emotion-modulation potential of sound (not of music) is lost, right there.

Low frequency fluctuations are beautiful. To understand how, one has to think about that PHASE is actually audible, also what goes on bellow the fundamental, be it small rooms or not. An example of fine, recorded signal of double bass transient and decay:

Impulse:

Step:

Mono:

L:

R:

Mono summing less in amplitude than the left channel (half of the attack itself is "lost in mono")

Phase:

GD basically "off the charts"

Enhanced autocorrelation (we are at 10Hz sub harmonic already at the cursor)

 

[ShadowFiend]

@Thomas Lund : Is there any practical way to achieve stereo bass and keep the in-room frequency response smooth (no noticeable dips/peaks)?

My idea is calibrate frequency response of each left loudspeaker with a group of 2-3 subwoofers located on the left side of the room, then doing the same with right loudspeaker and another group of 2-3 subwoofers located on the right side of the room. So for each side we can get reasonable flat frequency response.

I would be appreciated if you can give some feedback to my idea.

 

[Thomas Lund]

Is there any practical way to achieve stereo bass and keep the in-room frequency response smooth (no noticeable dips/peaks)?

My idea is calibrate frequency response of each left loudspeaker with a group of 2-3 subwoofers located on the left side of the room, then doing the same with right loudspeaker and another group of 2-3 subwoofers located on the right side of the room. So for each side we can get reasonable flat frequency response.

Mastering studios and theatres have controlled acoustics, and don't rely on bass "management". Two major advantages over home reproduction, with which I have less practical experience.

Your method would clearly be better than a mono sub at preserving and conveying AEV latent in a recording. The result, however, also depends on room acoustics, audio format and listening distance, so you might start by looking at Early/Late FR graphs at the listening position(s), like discussed on other threads.

Anyway, please post the findings - especially how it sounds - if you take the plunge.

 

[TimVG]

Would I be correct to assume that the smaller the listening room, the less perceived the effect would be starting from the lowest octaves? Question in mind with practical application for selecting mains to subwoofer crossover for a given room size, with perhaps a balance so that magnitude response remains acceptable as well.
Can you suggest one or two reference test tracks that allow the effect to be maximally perceived?