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What makes speakers "disappear " and can it be measured?

ouimetnick

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I also find that a properly recorded song to be very important as well. You can have the proper equipment and proper placement, but you still need a properly recorded track.
 

Jim Matthews

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The stands include a subwoofer and an adjustable up-and-back firing coaxial driver, whose output contributes to the reverberant field (yeah I know that term in imprecise when applied to the size rooms we use, but imo it conveys the idea well):

View attachment 144540

Wow.

My Christmas list just got longer.
 

Duke

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Wow.

My Christmas list just got longer.

We now have an improved version of that stand, which goes a bit deeper and is more readily adaptable to a wider range of stand-mount speakers (the version in the photo is optimized for our stand-mount speaker). We call it the "SuperStand", because there simply is not enough hyperbole in high-end audio these days.
 

gvl

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I didn't experience too many speakers, but the ones that consistently disappeared were the JBL L100 Century's, while sounding awful. Go figure.
 

richard12511

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5. Using reflections in the room with a delay of 20 ms or more, to fill up the ”flawed” stereo 2-channel system, thus creating a better illusion from the recording event.
.

I'm pretty sure this is what Auro3D does(or tries to do). Putting me ear up to any of the surrounds/heights, all I hear is reverb. If I mute the mains with GLM, it sounds like listening to a reverb effect.
 

dualazmak

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Really interesting thread.

After recent completion of my multichannel multi-driver (multi-way) multi-amplifier system, myself, my wife and many audio-enthu guests/friends in our living room feel all the SPs are almost perfectly disappearing while listening to nicely recorded music tracks, like my "audio sampler tracks". The feeling remains unchanged even we move in 1 m range left-right, up-down, back-front, from the center of my usual listening position which is about 3.65 m from the surface of the SPs (please see the photo of listening room in my post here.)

The details of the room environments and conditions can be found in this post.

Even though I can guess many reasons and factors contributing to the "disappearance of the SPs" in my current setup, configurations and room environment, it would be quite difficult to objectively measure and prove the "disappearance of the SPs". I just would like to invite all of you in this thread to my home for our audio listening sessions...
 

JeanMiK

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Really interesting thread.

After recent completion of my multichannel multi-driver (multi-way) multi-amplifier system, myself, my wife and many audio-enthu guests/friends in our living room feel all the SPs are almost perfectly disappearing while listening to nicely recorded music tracks, like my "audio sampler tracks". The feeling remains unchanged even we move in 1 m range left-right, up-down, back-front, from the center of my usual listening position which is about 3.65 m from the surface of the SPs (please see the photo of listening room in my post here.)

The details of the room environments and conditions can be found in this post.

Even though I can guess many reasons and factors contributing to the "disappearance of the SPs" in my current setup, configurations and room environment, it would be quite difficult to objectively measure and prove the "disappearance of the SPs". I just would like to invite all of you in this thread to my home for our audio listening sessions...

I'd say that's the carpet in front of the speakers that make the difference.
I also have carpets between my speakers and listening place. Wherever you are in the room you can't hear anything coming from any speaker.
I have been in many places where friends and relatives have stereo setups. No carpets : horrible sound and hearing speakers.
Thing IS it's not trendy these days .....
 

Jim Matthews

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I'd say that's the carpet in front of the speakers that make the difference.

s-l1600-18-1.jpg

Pizza crumbs optional.
 

Thomas_A

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While thick large carpets are very good, I have a some questions of the coffee-tables placed in front of the sofas. Some (most?) people say they are poor for the sound due to the reflective surface. However, I have seen opposite benefits since they block the first reflections from the floor reaching your ears. Doing the mirror experiment, the floor reflection that should reach your ears will instead be stopped by the table. And doing the mirror experiment with the coffee table, there is no loudspeaker driver to be seen on the table; i.e. no reflections from the table are reaching your ears in most cases. Perhaps your stomach will get some of these reflections. So what are your thoughts? Is the "detrimental coffee table" an audio myth?
 

JeanMiK

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While thick large carpets are very good, I have a some questions of the coffee-tables placed in front of the sofas. Some (most?) people say they are poor for the sound due to the reflective surface. However, I have seen opposite benefits since they block the first reflections from the floor reaching your ears. Doing the mirror experiment, the floor reflection that should reach your ears will instead be stopped by the table. And doing the mirror experiment with the coffee table, there is no loudspeaker driver to be seen on the table; i.e. no reflections from the table are reaching your ears in most cases. Perhaps your stomach will get some of these reflections. So what are your thoughts? Is the "detrimental coffee table" an audio myth?

See my covered coffee table .....
 

Thomas_A

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See my covered coffee table .....

That would be one exception due to the close listening distance. You have a rather high ratio of direct to indirect sound in that setup.
 

dualazmak

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I'd say that's the carpet in front of the speakers that make the difference.
I also have carpets between my speakers and listening place. Wherever you are in the room you can't hear anything coming from any speaker.
I have been in many places where friends and relatives have stereo setups. No carpets : horrible sound and hearing speakers.
Thing IS it's not trendy these days .....

I agree, that should be one of the contributing factors. In my post here, actualy I wrote as "The ceiling is covered by microporous diatom panels carefully selected with proper sound absorption performance. On the wooden floor, we have the large carpet also selected with suitable sound absorption properties." Yes, I believe the selection of ceiling material/shape would be also important.

As for the room size, I believe the enough open space behind the SPs and also behind my listening position, i.e. the acoustically "dead" tatami-mattress Japanese style room behind me, are also contributing.

Please let me add that after I fully eliminated the LC-network (capacitors and inductors) in my multichannel multi-way system, the direct drive of each of the SP drivers by dedicated amplifier is further effectively enhances the "disappearance of SPs", maybe due to better phase/delay nature.
 

rgpit

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Scanned through this thread and I did not see any reference to the precise matching of right and left channels/speakers. I've found any variation causes the image to wander and the "holographic" effect collapses.
 

BenB

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There is direct evidence that floor reflections help us localize speakers:

Auditory localization: effects of reflecting surfaces:
https://pubmed.ncbi.nlm.nih.gov/2130378/
The results show an overall increase in correct localizations with a sound-reflecting surface on the floor.

So if you want a speaker to disappear to the greatest extent possible, you'll want to reduce that reflection. I anticipate Toole commenting that the floor reflection sounds "natural", and that we probably appreciate the impact it has on spectral balance. I'd suggest reducing the floor reflection and using EQ to obtain the desired spectral balance, which may not be completely flat on axis.

In addition, there is evidence that the ratio of forward to lateral sound is important for our perception of envelopment. Floor and ceiling reflections re-enforce the forward sound. In stereo, the major components of the forward sound are the direct sound, floor reflection, the ceiling reflection, and the front-wall reflection. The sidewall reflections (ideally delayed more than 5ms) constitute the lateral sound. By reducing the floor, ceiling, and front wall reflections, we decrease the ratio of forward to lateral sound, improving our perception of envelopment. This also increases the apparent soundstage width. Again, this may require deviating from the standard of flat on axis sound to some degree. Another way of improving the forward to lateral sound ratio is by exaggerating the sidewall reflections or supplementing them with additional speakers. It's my opinion that this approach has a negative effect on clarity when compared to the approach of reducing floor, ceiling, and front wall reflections.
 

Tangband

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While thick large carpets are very good, I have a some questions of the coffee-tables placed in front of the sofas. Some (most?) people say they are poor for the sound due to the reflective surface. However, I have seen opposite benefits since they block the first reflections from the floor reaching your ears. Doing the mirror experiment, the floor reflection that should reach your ears will instead be stopped by the table. And doing the mirror experiment with the coffee table, there is no loudspeaker driver to be seen on the table; i.e. no reflections from the table are reaching your ears in most cases. Perhaps your stomach will get some of these reflections. So what are your thoughts? Is the "detrimental coffee table" an audio myth?

A coffe table can be good because, as you say, they block the first reflections from the floor reaching your ears.
A coffe table can be bad if there is no damping material on the table. Without a table-cloth theres gonna be lots of reflections at high frequencies and if they are within 5 ms from the direct sound from the loudspeaker reaching your ears, you get ugly colorations . Early reflections in the treble area are especially bad for sound quality.

Remember - early reflections within 5 ms sounds bad both from loudspeakers in your home, and when you do recordings with microphones, while late reflections, more than 20 ms, are often beneficial with the flawed stereo reproduction.

Its very important to have a thick rug on the floor in front of the loudspeaker, for the reasons above. Reflections from the roof is much less disturbing, arriving at your ears more than 10 ms after the direct sound from the loudspeaker.

I would say a thick rug on the floor is much more important for good sound, than damping material behind the loudspeaker at the front-wall. Because interference at higher frequencies is much worse for a good sound than interference below the rooms schroeder- frequency ( SBIR ).
 
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