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How NOT to set up speakers and room treatment ( Goldensound)

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Axo1989

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RT60 (Reverb Time) is a global measure of the room, "same in all spots" > that's why you need a diffuse field.
T60 is a local measure of decay in the room, specific to one emiter & reciever spot.

Simple expl is your T60 at the frequency of first length mode can be very long close to the wall and almost non existent in the perfect center. It's not position invariant > RT60 has no sense.

Good explanation of the phenomena (even though I haven't seen the nomenclature used in that way). I've assumed measuring T30 (etc) at LP for the approximation, but as you say, an oversimplification of the room.
 
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BrokenEnglishGuy

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BTW, as I noted earlier, dips are not very audible. Here is a recent study by Dolby&HP on audibility thresholds of dips:
Equalization of Spectral Dips Using Detection Thresholds Sunil Bharitkar1 , Charles Robinson2 , and Andrew Poulain2 1HP Labs., Inc. 2Dolby Laboratories., Inc.


View attachment 289293

The dips are usually very narrow and hence high Q. We see that at say, Q=10 at 65 Hz, you can tolerate up to -13 dB before you can even detect them. As such, if you have a dip, you don't have to fill it all in. Or at all.
I got a dip for having a floorstander in my small room at 120hz~, I got the umik 1 for 2 days and EQ the R and L channels apart. To be honest it brother me of seeying like a 10dB boost in that area... but it sound normal with the EQ, better than if is not fill
This is the left chanel, i know... it looks weird but sound very normal
1685632267616.png
 

d3l

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I tried a totally unscientific and subjective experiment yesterday by removing the side wall absorption at first reflection points, and removing the sidewall absorption/diffusion just behind me whilst leaving front/rear of room as is. (I didn't remove them personally, got my rather bemused mum to remove them for the afternoon)

Just so we're absolutely clear I have absolutely zero/zilch/nada/not a fu£king jot of acoustic training so this purely based on what I heard, the room was set up a few years ago by a mate who works in the industry using rew/umik mic and his 30+ years of work in studios)

Front of room
4 tri traps with membrane range limiter, 2 4" absorption panels with tuned membrane and 1 4" absorption/diffusion
51724319233_a597d2d68e_c.jpg


51724950910_32991db8ac_c.jpg

3 2" panels on ceiling

Rear of room
Rear of room with 8" bass traps with tuned membrane and 4" absorption/diffusion

50933084102_42e2c839ab_c.jpg


I removed the 4 side wall panels shown below (old pic, ignore my previous krk's, these are all old pics)

50932274233_2f2bcd4cfb_c.jpg


50932274713_929e71031b_c.jpg


I sat and browsed my usual listening of electronic/electronica such as Jon Hopkins, Craven Faults, Underworld, Moby, Carl Craig, Rival Consoles, Chemical Brothers, Daft Punk, Dave Clark, Loscil etc...etc.

The sound in listening position in front of monitors was undefined, less direct snap, less impact and the side wall reflections were rather annoying for my preferred musical choice.

So today the panels are back up and I'm a very happy bunny today.

This concludes my totally unscientific subjective appreciation of how my room sounds with/without side wall treatment

Thanks for this. This is exactly why you see the treates sidewalls in about 99% studios.
 

wadude

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if the mods think this isn’t appropriate please remove.

it just irks me that this guy is 24 years old , this is his FIRST room with speakers and he made a video on it.
and it’s a bunch of BS.

his room has an RT60 of 250ms. its a room NOT headphones.
he shows an impulse response and says he needs to get rid of ALL reflections.
He needs to desperately read Floyd Toole who has spent decades on research. Not 2 years.

then he goes on to stick all panels right up against each other.
when does it end??
I am on the internet , therefore I am.
christ.

The aesthetics of the room don't appeal to me and I wouldn't enjoy sitting in it even with the sound off. Where are the books, the art, the coffee table? There's only one chair. Where do my friends and family sit?
 

fpitas

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The aesthetics of the room don't appeal to me and I wouldn't enjoy sitting in it even with the sound off. Where are the books, the art, the coffee table? There's only one chair. Where do my friends and family sit?
The music was hard to make, it should be hard to listen.

/;)
 

fineMen

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RT60 (Reverb Time) is a global measure of the room, "same in all spots" > that's why you need a diffuse field.
T60 is a local measure of decay in the room, specific to one emiter & reciever spot.

Simple expl is your T60 at the frequency of first length mode can be very long close to the wall and almost non existent in the perfect center. It's not position invariant > RT60 has no sense.
You're sure that makes sense? Since there is no 'decay' of a single (!) frequency.
 

Zensō

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The aesthetics of the room don't appeal to me and I wouldn't enjoy sitting in it even with the sound off. Where are the books, the art, the coffee table? There's only one chair. Where do my friends and family sit?
That room appears to function as a set of room-sized headphones in more ways than one.
 

Somafunk

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There's only one chair. Where do my friends and family sit?

There’s only one chair in my living room, except for my computer chair. Suits me fine.
 

MattHooper

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Why do we like it that way? Because we associate that with realism. From the book above:

"The most neutral sound reproduction is usually not the goal of sound reproduction except in the control rooms of sound recording studios. In homes, both for music appreciation and home movie theater, the goal for many listeners is rather suspension of disbelief a term used in presence research.

Kleiner, Mendel; Tichy, Jiri. Acoustics of Small Rooms (p. 275). CRC Press. Kindle Edition. "

Ha. Indeed. I've encountered many audiophiles who say the goal of sonic realism is silly - out of reach, stereo can't do it, recordings are too artificial etc.
All of which has some truth obviously. But as I've said, if we have *any* common references for "good sound," among them is certainly "sounds more real."

As to aiding the illusion with reflections, as I've mentioned before: I have a fair amount of flexibility since I have curtain tracks that span the length of all my walls, and thick velvet curtains that I can pull along to any point, and bunch them or expand them to cover whatever portion of the wall I want. Also my 2 channel speakers sit in front of my huge wall-sized projection screen and the screen has automated 4 way masking made of black velvet. That means, by changing the area of the screen covered with black velvet (from entirely open to entirely covered or anything in between of different shapes) I can greatly alter the reflectivity/absorption (higher frequencies) of the wall behind the speakers with great precision. Plus I have some diffusion that I can play with.

So if I want the specific acoustic (natural or artificial) of a recording to have prominance I make the room more dead in the right places. I find this produces what I often think of as "The Portal Effect." It puts me in the mind of the Time Portal from the classic Star Trek episode City On The Edge Of Forever, through which various scenes from past history could be observed:

https://static.tvtropes.org/pmwiki/pub/images/rsz_wchter_der_ewigkeit_2267_2253.jpg


So the very specific acoustics/reverb and imaging of the recording opens up between and behind the speakers, sounding quite distinct from the room I'm in, like the speakers have become a portal that I'm peering through to another acoustic/event. Which can be really cool.

Other times I want more reflection and especially for listening to orchestral music. But it's a careful balance because I want to hear the acoustic qualities of the recording, and the more room reflections I allow the more those become homogenized, and also if the room is too live it starts to sound like the orchestra is now in my small room - like I've imported a small orchestra in to the room behind the speakers.

I find if I get the balance of reflection just right (I have markings for it), then a sort of magic happens in terms of the illusion. The acoustic of the recording dominated but there is just enough room reflection to ease away the boundaries, the hard lines, of the soundstage created by the recorded acoustic...and then the sense of acoustic space just seems to open up. So the sensation of my sharing the acoustic space, of peering through significant acoustic depth in to a hall to an orchestra, is quite convincing (with a little help from my imagination of course).

So one of the goals I have for how my system sounds is that, when I want, I can get the sensation of "instruments playing in free space" similar to what I hear live, vs sounding canned and contained in some sort of artificially squeezed acoustic.

Every time I go to a live concert, I listen to see if I can hear "pin point imaging" and it is never remotely there. Everything is diffused. That is what reflections do.

Just like you I pay attention to imaging when listening do live acoustic music. I certainly hear imaging (and I've always tended to favor the closer seats at symphonies).
Is it "pin point?" That can be hard to agree upon because it's pretty subjective what we might mean by "pin point," as in how precise does it have to be for any particular individual to think "this is pin-point imaging!"

Where I live, in a downtown-adjacent area, there is almost constant live music being played in the streets - usually small folk or jazz groups, live un-amplified instruments. When I stop, close my eyes and listen for imaging it's actually pretty close to plenty of small group recordings I play on my system.
I would say that the live imaging is actually quite precise - I can point to exactly where the trombone player is and that he is several feet in front of the drums etc.
So it shares some imaging precision with my system but the live imaging is not "pin point" in how I think of it, because sonic images in recordings I find are themselves squeezed in to tinier versions. So your average trumpet section in a funk recording sounds like they've gone through a black hole and been reduced to toy size vs a live horn section in front of you. Likewise for any single instrument in most recordings. Drum cymbals that in real life sound like large resonating metal discs become tiny little bright spots of sound in most recordings. They are "reduced to pin point images" in the soundstage. So in that sense I don't associate live sound with pin point imaging.
 
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Cubic Spline

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You're sure that makes sense? Since there is no 'decay' of a single (!) frequency.
I'm not sure I understand what you said by there is no 'decay' of a single frequency ?
RT60 and T60 are 2D graphs of time vs frequency (that can be more or less smoothed).
 

Geert

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Another reason for the preference of less reflection is hearing loss.

And Toole continues: "In Figure 22.3 at the end of my book presents suggestions for room treatment based on guidance from research. The portions of side walls responsible for first lateral reflections are specified as “optional areas: absorb, diffuse, reflect.” It is a decision to be made by the customer and/or the installer".
 

hemiutut

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So far I have already read the 30 pages and I see that it is giving a lot of play
as a result of the video posted in the first comment.

To say that I think the same as the fan tuga about Dr Toole's room,
it is not at all what I am looking for in terms of acoustic treatment.
I understand perfectly well that it is a family room and the aesthetic tastes of each person.
That yes,he is very clear about the benefits of a multisubwoofer configuration,in this case he has 4.

Having said that, I have to say that I like a room as neutral as I can get,
since I have to combine my hobby (watching movies, multichannel TV series, etc.)
with my hobby (watching movies, TV series, etc.).
vs music in stereo 2.1) with family life in my living room.

I see that you mention a lot the RT60 and it is necessary to take it.
with a lot of caution.
The RT60 in small rooms is not a conclusive data.
to accept it and that's already years ago that there are many people who defend it.
Acoustically small rooms are practically the majority we have,
no matter if the room is 8, 15, 30, 50 or more meters,
they are still acoustically small rooms.

And having said that I recommend you this video,surely after
you will have many reflections on the subject.



Written with translator

Greetings
 

TheZebraKilledDarwin

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Another reason for the preference of less reflection is hearing loss. (source)
View attachment 289632

Is my impression correct, that hearing loss is mentioned as reason for preference for less reverberant rooms, but the most important reason, the necessity for the professional to hear, judge and create the ambience in every mixed track, is not mentioned? What if I want to hear the ambience in the track, because I listen carefully into the mix and want to hear these (and other) details?

I also do not like the focus on the ear, because we are not hearing with the ears, but with the brain. The best ears of young people are worth nothing, if they are untrained (trained ears = brain has been trained to listen for certain criteria).

Btw, I am still waiting for an answer, for those arguing for reverberant rooms, how the ambience in a track can be heard in a reverberating room?
 

NTK

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Btw, I am still waiting for an answer, for those arguing for reverberant rooms, how the ambience in a track can be heard in a reverberating room?
The simple reason is that the reflected sound we hear in concert halls comes from every directions, not just from 2 loudspeakers, one 30 degrees to the left, the other 30 degrees to the right. Lateral reflections of the room help some, but multichannel works much better.
 

Purité Audio

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I believe 2L’s Moreton is quite keen to capture something of the original venues acoustic.
Keith
 

goat76

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Since we are sort of on topic ... I have heard that RT60 and RT30 are not applicable in small room acoustics. Is this true?

If you are using REW, the graph in the "RT60 Decay" window is supposed to suit the small room's acoustics better than the old regular RT60, which is more suited to large rooms like symphony halls.

This is RT60 Decay of my listening room. The curve that overlap the waterfall should not deviate too much in amplitude over the frequency range.

1685644807801.png


Gene from Audioholics explains well how you set it up and generate the calculation in REW in the following video.

 

tuga

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I believe 2L’s Moreton is quite keen to capture something of the original venues acoustic.
Keith

You believe wrong, he places the listener in the middle of a circle formed by the instruments.
As far from live as possible, and harldy anything remotely like spatial cues.

04-Fig01-2L-SetupFig.jpg

 
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