My room

[Washington]

Out of pure curiosity, what kind of music do you listen to in such an impressive environment ? Is that a Stanley Clarke / George Duke LP I see there ?

And on a side note... I assume there must be a door to get in and out of there, but I can't seem to locate it. Where is it ?

[Torea]

Originally Posted by Washington

Out of pure curiosity, what kind of music do you listen to in such an impressive environment ? Is that a Stanley Clarke / George Duke LP I see there ?

And on a side note... I assume there must be a door to get in and out of there, but I can't seem to locate it. Where is it ?

Why would you need a door to get out once you step foot in there? Just have a handyman seal up the hole after you enter

[Providence]

Is this setup for a studio or just your own personal listening environment? If it's just a listening environment then...... damn!

[Mctwins]

Hi
Ok I will show you the ETC curve



To activate the room properly I decided to run both of my speakers together. If you put this curve into Matts SMT concept of S-room acoustics(Early reflections following the Spacioussness Field) one can see that the room need some more treatment, probably some Wing diffusors on the first reflektion on the floor to be classified as a SMT Level 3 room acoustics. But I think I can live with this as long as I now what the problem is.

This is my listening space and whatever music I play it sounds great and has great dynamics and good and even power response thru the freq spectrum.

There is a door, but you don't see it because it is behind the Wing diffusor, where the airconditioner is located.

Thanks

[Mctwins]

Here is CSD.

[octave]

Mother of f*ck! (in a good way)

[localhost127]

Originally Posted by Mctwins

Hi
Ok I will show you the ETC curve




Thanks

fun room!

there's a loud early reflection there - likely off of the floor?

[capoeira]

Originally Posted by Washington

assume there must be a door to get in and out of there, but I can't seem to locate it. Where is it ?

door for what? I guess he forgot it and is now prisoned (without actualy noteing it).
But why would one access the i-net after building this room?

[Mctwins]

localhost127....

How do you know it is a floor reflection??

I think it has to do with the two impulse response due to the two loudspeakers involved when measuring. I will test with only one speaker and report back.

Thanks

[Mctwins]

Here is a fantastic Burst Decay truncated at 19ms.



This picture shows how even and broadband SMT diffusion concept works and this also shows the JBL:s loudspeakers even power response. This gives the listener an oppertunity to hear the recording room and all the timbre that one can hear in voices and instrument. Reason to the short time window is because it is only relavant to see from 1500Hz and above (If I have larger time window in the ARTA, it looses it's resolution up in the frequency).

This is the holy grail of diffusion.

Thanks

[bwo]

Originally Posted by Mctwins

localhost127....

How do you know it is a floor reflection??

I think it has to do with the two impulse response due to the two loudspeakers involved when measuring. I will test with only one speaker and report back.

Thanks

When measuring the ETC, the speakers needs to be measured invidually. It would also be good if you can zoom in. It's not important in a small room what happens after about 60 ms.

[localhost127]

Originally Posted by bwo

When measuring the ETC, the speakers needs to be measured invidually. It would also be good if you can zoom in. It's not important in a small room what happens after about 60 ms.

measuring one speaker at a time is for when you are identifying early reflections (boundaries/surfaces) - because you need to know the total flight path, hence...you need to know specifically which speaker the energy is incident from.

[boggy]

Originally Posted by Mctwins

......
I think it has to do with the two impulse response due to the two loudspeakers involved when measuring.....

It's about 3ms delay between pulses (if I can see good), so, this is about 1m difference in distance from different sources to measurement microphone...
This behavior can't be from two different loudspeaker locations or your measurement microphone is closer to the first loudspeaker for about 1m than to second loudspeaker...

I agree with others, room measurements need to be done with only one channel, left or right.

[erikdrink]

Very impressive!!!

[Mctwins]

Thanks, the sound is very impressive as well.

It is 1,5ms between left and right, as I see it.

Just give me some time to do the measurement with only one speaker, because I have a pepair man how is renovating my bathroom and it is little bit dirty when I have to enter my listening room. I promise, but I have to do this next week.

Thanks

[Mctwins]

Hi
I just want to show the freq response before the treatment. A room that was totally empty. Dimension is 7*4,8*3 meters, and this is very well in the Bolt area and the intresting thing is that there is severe peaks and deeps in the bass area. So, this means that the dimension ratio according to Bolt, as I see it, is irrelevant. It seems that it works fine in the theory but it is not applicable in practice. As you can see in this measurement.



This didn't help anything if I moved the speakers or the mic in various location. I can today say that one can treat any kind of room ratio and get a result of flat freq response and with no resonances (if Helmholtz resonators is being used). What I mean, if one have a room that is 5*5*5 meters it is treatable.

Reason for showing this is becasuse there was a disscusion of my room dimension and slanted wall in another thread.

Thanks

[hsal]

Impressive achievements, I guess one the reasons that the helmholtz resonators work so well is that there is created a new boundary with all the acoustic treatment, hence the opening of the helmholtz resonators is placed close to the boundary.

[localhost127]

+1 for pressure-based traps.

are they home-made?

it's a 2ch setup, correct? any consideration regarding haas trigger or any sort of termination in the specular response?

thanks again

[Jeffrey Hedback]

McTwins,
First, your room, methods and results are great. I do question the pre/post measurements as being 1:1. To my understanding (from seeing posts on other forums), your pre measurements were made with two different fullrange "floorstanders". Your wonderful "after" measurements are different speakers (in different locations) and have at least (4) LF drivers (cross-over depending) at any point in the LF range (not just two as in the previous). The addition of multiple LF drivers will create modal averaging and smooth out the LF response (in addition with your proper use of the Drive Rack processor). Is my statement correct?

Again, great work. I'm sure it sounds absolutely wonderful.

[Mctwins]

Hi
I am sitting very close to the Wing diffusor and this is shown in the ETC curve just after the first floor reflection. Also, due to that I'm sitting so close to the Wing diffusor that I don't care much about the ISD gap.





Matts of SMT don't like diffusor of today, because they don't work very well in small room acoustics beacasue if they are made broadband one have to sit very very far away and in that case they are loosing their task and the abillity to unmask the transients in music.

To cure this problem Matts has introduced a family of Wingdiffusor that shortly will be released in the world market.

As one can see in the ETC curve is that the incoming signal is evenly spread out over time due to the two Wingsdiffusor behind the sweetspot and this gives the brain a chance to hear all that timbre in voices and in acoustical instruments and to unmask those powerful transients so that the listener has an oppertunity to hear the early reflection in the recording room and maintain a more dynamic sound.

After 15ms the Golden Horn shows, still after 15 years, it's worldclass. The evenes lies in it's fractal design witch means that they are not cast in the same form(no Golden Horn is ever the same).

Above very short, I have a room that measure like a wet dream for music lovers.

Thanks

[Mctwins]

Originally Posted by Jeffrey Hedback

McTwins,
First, your room, methods and results are great. I do question the pre/post measurements as being 1:1. To my understanding (from seeing posts on other forums), your pre measurements were made with two different fullrange "floorstanders". Your wonderful "after" measurements are different speakers (in different locations) and have at least (4) LF drivers (cross-over depending) at any point in the LF range (not just two as in the previous). The addition of multiple LF drivers will create modal averaging and smooth out the LF response (in addition with your proper use of the Drive Rack processor). Is my statement correct?

Again, great work. I'm sure it sounds absolutely wonderful.

Hi, and thanks.

Yes you are correct about the speakers. When I started to treat this room I had another set of speakers. But I don't understand what the diffrence is when coming to measure a room. I have a pair of speakers and a microfon and between a program that can evaluate in between.

The goal was to make the room to suite every kind of speakers and not vice versa. And I can say that this room will take any speakers, but this I leave for you to decide if it is so.

I can't go back and redo everything just to show you that it doesn't matter what kind of speaker and location when measuring. This I have already come to conclusion that it doesn't matter.

To have multiple drivers in LF will not create modal average and smothens the response. This can only be done if Helmholtz tuned right to the problem that the room have. And only then the LF will behave accordingly. Basically what I mean is that multiple LF drives can not minimize resonance and the modal decay only properly tuned Helmholtz resonator can.

What I have shown is that with this system witch have high SPL and dynamics with good power response works very well with this kind of acoustic treatment.

So this menas that I don't agree with your statement.

The DSP is needed when having these speakers, because of bi-amp and crossovers setting.

Thanks

[Mctwins]

Hi

Jeff...
I forgot, thanks for the kind words regarding my great work on my room.

Thanks

[johndykstra]

Hi McTwins,

seems I've tracked down the thread about this room of yours. I must say, it's stunning. Your avatar photo doesn't do it justice.

One glaringly obvious distinction that should be made between your listening room and the primary function of this design forum, is that the principles discuss here are typically for critical listening spaces, not pleasure listening spaces. There is a difference. Now, I have no doubt that your room is likely far superior to the mixing rooms that a large percentage of engineers are working in acoustically. However, there have been, over the course of decades "rules" about the behavior of early reflections that your room cannot adhere to given it's topology. These rules, I'm comfortable in saying, are written by individuals far smarter than you or I.... sorry.

There are a few "trailblazers" who are rethinking our current early reflection criteria. I need not point this out to you, we've been in the same trenches. While it would truly be a shame to completely dismiss these new early reflection theories as "audiophilia run a muck", it'd be equally frustrating to completely ignore the research that has already been done... as if to say "nothing that proceeded this room model (in it's infancy) is as good".

Cheers, and again, what a tremendous room you have,

John

[jhbrandt]

Mctwins,

A big +1 on John D's comments above.

Very, very nice room indeed. I would love to hear it! Please note; I Am an audiophile.

Cheers,
John

[Mctwins]

Originally Posted by johndykstra

Hi McTwins,

seems I've tracked down the thread about this room of yours. I must say, it's stunning. Your avatar photo doesn't do it justice.

One glaringly obvious distinction that should be made between your listening room and the primary function of this design forum, is that the principles discuss here are typically for critical listening spaces, not pleasure listening spaces. There is a difference. Now, I have no doubt that your room is likely far superior to the mixing rooms that a large percentage of engineers are working in acoustically. However, there have been, over the course of decades "rules" about the behavior of early reflections that your room cannot adhere to given it's topology. These rules, I'm comfortable in saying, are written by individuals far smarter than you or I.... sorry.

There are a few "trailblazers" who are rethinking our current early reflection criteria. I need not point this out to you, we've been in the same trenches. While it would truly be a shame to completely dismiss these new early reflection theories as "audiophilia run a muck", it'd be equally frustrating to completely ignore the research that has already been done... as if to say "nothing that proceeded this room model (in it's infancy) is as good".

Cheers, and again, what a tremendous room you have,

John

Thanks

I agree that there is alot smarter people. I know also that there is lot's of rules regarding the early reflection, but my feeling is that this is irrelevent because, this with early reflections is working for me, thats all. I was not aware of this when I started with my room, only I liked diffusion before 100% absorption in small room acoustics.

I feel that this reaserch with early reflection is interesing
and will follow it's development.

Cheers and thanks again

[Mctwins]

Originally Posted by jhbrandt

Mctwins,

A big +1 on John D's comments above.

Very, very nice room indeed. I would love to hear it! Please note; I Am an audiophile.

Cheers,
John

Thanks John

You are more than welcome for an listening session

Thanks

[localhost127]

Originally Posted by Mctwins

I was not aware of this when I started with my room, only I liked diffusion before 100% absorption in small room acoustics.

Mctwins,
prior, did you have 100% absorption within the room? a completely dead room (within the specular region)?

creating the ISD-gap is an effectively anechoic time-period, but it needs to be terminated (otherwise, one would have an infinite ISD-gap which is a dead room).

ideally, splayed walls (geometry) is used at early reflection points due to the nature of specular energy being finite within the room. the splayed walls will redirect the specular energy away from the listening position towards the rear wall where it can be diffused and returned to the user to terminate the ISD-gap. splayed walls are preferred over absorption, as one needs the termination to be as high in gain as possible - and absorption is removing precious energy from within the room.

it's quite common for people to go overboard with specular broadband absorption, when once the principles are learned - the opposite path is taken (and it now becomes an issue to maintain as much energy within the room for good, dense decay).

was your room 100% absorption before going the all-diffusion route? thanks,

[Mctwins]

Originally Posted by localhost127

Mctwins,
prior, did you have 100% absorption within the room? a completely dead room (within the specular region)?

creating the ISD-gap is an effectively anechoic time-period, but it needs to be terminated (otherwise, one would have an infinite ISD-gap which is a dead room).

ideally, splayed walls (geometry) is used at early reflection points due to the nature of specular energy being finite within the room. the splayed walls will redirect the specular energy away from the listening position towards the rear wall where it can be diffused and returned to the user to terminate the ISD-gap. splayed walls are preferred over absorption, as one needs the termination to be as high in gain as possible - and absorption is removing precious energy from within the room.

it's quite common for people to go overboard with specular broadband absorption, when once the principles are learned - the opposite path is taken (and it now becomes an issue to maintain as much energy within the room for good, dense decay).

was your room 100% absorption before going the all-diffusion route? thanks,

Ok, I got you. It was clumsy of me. What I really ment was visible broadband absorption. If I substitute diffusion with absorption. Hope it make sense.

It was not 100 % absorption, but the fact is that I never liked to use visible absorption. It only make the room dead, ineffective as a low freq absorber and so on.

[Mctwins]

Ok, let me explain a bit about the absorption when I first started to treat my room for five years ago. I have another room downstairs and it was in this room I started.

On my front wall, I coverd it with Dacron 100mm with an airdepth of 100mm and a size of 4,5*2,4 meter with corner traps angeld 45 degress and had first and second reflection point off my side walls and first reflection point on the ceiling also with dacron of 1200*900*100mm. The strange thing a notice when I listening to music was that my eardrum was hurting, it was really painfull. It was so dead that I coulden't listen anymore. One didn't notice this painfullness when normal conversation accure. It sounded better when I removed those Dacron and left my wall with nothing on it. The pain was more noticeble when I played with higher SPL. This was very strange experiance.

I replaced it with diffusion (same size) and it was totally differen't. I really didn't understand how it could be so differen't compare with absorption contra diffusion at that time.

All I want to say is that I tried LEDE concept maybe not excactlly according to the rule of LEDE.

When I measured this room I didn't notice any changes below 100Hz when I had Dacron. When I put HH resonators then I saw something started to happend.

This room is 14meter long with adjacent openings rooms like kitchen and so on and the first wall is about 10 meters long. I mean a big room.

This is my currently room downstairs. In this current setup I don't have so much HH than before, only four of them. Most part of them is upstairs.



You see the slat panel resonators with MDF board, 19mm thick, behind the speakers above the diffusion has 4mm of slats, volume is around 1,5 cubicmeters, even this dosen't help below 100Hz, Don't see any changes in my measurement as well.
The only changes I saw when this slat came up was around 150-350Hz.

This is the reason I don't like visible absoption.

Thanks