Soft Flush mount specs

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Gregwor
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Re: Soft Flush mount specs

Post by Gregwor »

Why do you need inspection hatches?
Earlier in his thread he explained this. Unfortunately there's no way for him to move the things in behind. And realistically, he never will need to access it, but I believe legally it needs to be accessible.
So i have my RFZ room? :D
Now i can proceed and start building?
Horizontally it appears that you've got it sorted.

Now design your cloud so that you can ensure your vertical reflections don't hit your head. In my personal experience, I've had to adjust where my speakers are in order to achieve RFZ in the vertical plane. So do this before you continue.
Here an idea for the inspection hatches...
A cutted piece of the same wood used for the baffles (maybe MDF), screwed up and maybe also with rubber gasket at the baffle wood stud structure...

You think it's ok? This don't will cause some tipe of artifact?
You should make them into absorption panels so they don't create artifacts. There's no reason you can't have the entire bottom portion of your soffits absorption with the air gap on the bottom like John's design has. This entire bottom could come off using decorative button head type screws.

Greg
It appears that you've made the mistake most people do. You started building without consulting this forum.
matt-korban
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Re: Soft Flush mount specs

Post by matt-korban »

Earlier in his thread he explained this. Unfortunately there's no way for him to move the things in behind. And realistically, he never will need to access it, but I believe legally it needs to be accessible.
Exactly!
Horizontally it appears that you've got it sorted.

Now design your cloud so that you can ensure your vertical reflections don't hit your head. In my personal experience, I've had to adjust where my speakers are in order to achieve RFZ in the vertical plane. So do this before you continue.
Ok i'll do.
You should make them into absorption panels so they don't create artifacts. There's no reason you can't have the entire bottom portion of your soffits absorption with the air gap on the bottom like John's design has. This entire bottom could come off using decorative button head type screws.
What do you think about something like that?
I can remove the inspection hatches, then the small angers under the speaker (I designed them this way) and have access to all i need...
inspection hatches 1.jpg
inspection hatches 2.jpg
inspection hatches 3.jpg
inspection hatches 4.jpg
inspection hatches 5.jpg
inspection hatches 6.jpg
inspection hatches 7.jpg
Gregwor
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Re: Soft Flush mount specs

Post by Gregwor »

A few things I notice:

- You should have the absorption lower section follow right around the bottom of the entire soffit and soffit wings as well! The missing bottom section only has to be for the part below your speaker (where you have it now) for ventilation. The rest of the soffit and wings can go right to the floor.
- You should put a wooden backer and frame around the raised absorption you added to prevent it from sagging or falling over time. This will prevent it from ever hitting your hangers or sliding down into the ventilation hole below.
- The corner hangers should go floor to ceiling.

Great work so far!

Greg
It appears that you've made the mistake most people do. You started building without consulting this forum.
matt-korban
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Location: Sardinia - Italy

Re: Soft Flush mount specs

Post by matt-korban »

Hey Greg!
You should have the absorption lower section follow right around the bottom of the entire soffit and soffit wings as well! The missing bottom section only has to be for the part below your speaker (where you have it now) for ventilation. The rest of the soffit and wings can go right to the floor.
I don't understand really well what you mean...
The absorption will cover all the floor surface of the soffit (maybe in sketchup it's wrong!).
I have build something today (and last days)... here some pics!
Let me know what you think...

I'll build the silencer box for air duct in the other room...

P.S.
- The wood stud that you see over the electrical junction box, it's not really over the box (don't touch the box), but it's fixed at concrete wall really well and solid.
- I have to add the absorption insulation around the speaker cabinet that i'll build soon, and add the ventilation duct (i don't know right name) rear at the speaker.
- My cloud angled ceiling, have to be attached really strong to the front baffle (to the soffit baffle), or can be a separate cloud hanging from the concrete ceiling?
IMG_20190122_183254.jpg
IMG_20190122_183308.jpg
IMG_20190122_183748.jpg
IMG_20190122_183846.jpg
Gregwor
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Re: Soft Flush mount specs

Post by Gregwor »

I don't understand really well what you mean...
I mean your hard soffit baffle material should only go down so far. Then the bottom section of both the soffit and the wing should be absorbent.
I have build something today (and last days)... here some pics!
Let me know what you think...
I think the hangers should go all the way to the floor. Now, I realize you need to have them removable there. If that's the case, maybe add another shelf below the existing hangers in the corner and add more hangers off it it.

How did you attach the top of the hangers to your soffit framing?

You also need the floor in the soffit to have insulation the same as you did the walls.
Also, you need insulation on the ceiling in the soffit.

You made sure the hangers are freely hanging not touching ANYTHING right?

I also feel you maybe should have boxed in you speaker mounting area better. That way when you stuff all of that insulation around your speaker enclosure, there's no chance of it rubbing up against the hangers.
I'll build the silencer box for air duct in the other room...
Can we see pictures of "the other room" and your SketchUp plans for the silencer box before you start?
- My cloud angled ceiling, have to be attached really strong to the front baffle (to the soffit baffle), or can be a separate cloud hanging from the concrete ceiling?
Either. Having it hung separately allows you to easily adjust the angle and fine tune it. Also, it allows you to remove it if you need to tweak something above. It won't look as seamless though. Up to you.

Greg
It appears that you've made the mistake most people do. You started building without consulting this forum.
matt-korban
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Re: Soft Flush mount specs

Post by matt-korban »

I mean your hard soffit baffle material should only go down so far. Then the bottom section of both the soffit and the wing should be absorbent.
Ok now i got!
I can build the bottom section absorber like the inspection hatches? Without rigid and massive wood behind or in front right? Only a rockwall or fiberglass panel, in a wood frame, covered by fabric? And i can make them removable like the inspection hatches?
maybe add another shelf below the existing hangers in the corner and add more hangers off it it.
Of course! Today i have do it.
How did you attach the top of the hangers to your soffit framing?
See here: (at the concrete ceiling)
Hangers detail.jpg
And here: (behind speaker enclosure)
Hangers detail 2.jpg
You also need the floor in the soffit to have insulation the same as you did the walls.
Also, you need insulation on the ceiling in the soffit.
I've added insulation today on the top of the soffit (ceiling) and i'll add soon on the floor.
You made sure the hangers are freely hanging not touching ANYTHING right?
Yes :wink:
I also feel you maybe should have boxed in you speaker mounting area better. That way when you stuff all of that insulation around your speaker enclosure, there's no chance of it rubbing up against the hangers.
What i've done today:
speaker baffle with insulation sustain.jpg
Can we see pictures of "the other room" and your SketchUp plans for the silencer box before you start?
Of course, but not soon...
I have to give priority to the control room for bureaucratic issues...
But, i need some advice maybe for place the air aspirator (IN air/OUT air). I'll let you know soon.

Either. Having it hung separately allows you to easily adjust the angle and fine tune it. Also, it allows you to remove it if you need to tweak something above. It won't look as seamless though. Up to you.
Ok ok, got it...
Maybe i'll have to correct a little frame error... i'll post a pic for let you see...

Other pics for you:
Front view.jpg
front with air duct.jpg
Electrical plant with insulation.jpg
Gregwor
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Re: Soft Flush mount specs

Post by Gregwor »

Ok now i got!
I can build the bottom section absorber like the inspection hatches? Without rigid and massive wood behind or in front right? Only a rockwall or fiberglass panel, in a wood frame, covered by fabric? And i can make them removable like the inspection hatches?
They don't need to be inspection hatch style. They should have a hard back as I mentioned before with insulation in front and hangers behind. Like this picture from John's recording manual:
Speaker EL.gif
What i've done today:
Attachment:
speaker baffle with insulation sustain.jpg
I would personally add some dimensional lumber on edge, or even some angle iron under the bottom shelf (the on that the speaker is going to sit on). I Put some under the front edge and another one across the middle of the shelf. That should better support where the speaker is going to sit and hopefully prevent more vibration.
Of course, but not soon...
I have to give priority to the control room for bureaucratic issues...
But, i need some advice maybe for place the air aspirator (IN air/OUT air). I'll let you know soon.
I know you're in a hurry but you REALLY need to be taking acoustic measurements along the way and posting the mdat files here for us. That way when there is an issue in the future, we know what caused it and how you can go about fixing it.

It's all looking much better than when you started!!!

Greg
It appears that you've made the mistake most people do. You started building without consulting this forum.
matt-korban
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Re: Soft Flush mount specs

Post by matt-korban »

Just a little question...
Can i use different material for front wall and soffit?

Like that: (white drywall, and brown MDF)
There is some design error because i have do the pics really fast! (just for explane my self)
Drywall and MDF.jpg

I will answer to the precedent message soon... This is only for take a fast decision now...
matt-korban
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Re: Soft Flush mount specs

Post by matt-korban »

They don't need to be inspection hatch style. They should have a hard back as I mentioned before with insulation in front and hangers behind. Like this picture from John's recording manual:
I would personally add some dimensional lumber on edge, or even some angle iron under the bottom shelf (the on that the speaker is going to sit on). I Put some under the front edge and another one across the middle of the shelf. That should better support where the speaker is going to sit and hopefully prevent more vibration.
Maybe something like that? You think it's good? (i don't know why is disappeared an anger! :lol: )
Under speaker 1.jpg
Under speaker 2.jpg
Under speaker 3.jpg
Under speaker 4.jpg
Under speaker 5.jpg
Under speaker 6.jpg
I know you're in a hurry but you REALLY need to be taking acoustic measurements along the way and posting the mdat files here for us. That way when there is an issue in the future, we know what caused it and how you can go about fixing it.
Ok of course! Thank you!
For now i have to do all the necessary for make "apparently finished" the studio (for contract expiry)... My business tutor, don't know when the studio it's really finished and start to working... so, only the necessary for appear good and finished before February 10th.
After i can do everything!
Soundman2020
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Re: Soft Flush mount specs

Post by Soundman2020 »

Sorry for the belated comments: been out of action for a while.

1) The speakers seem to be very close to the inner-edge of the soffit baffle. Yes, they should be offset a little, but that's more than "a little". Ideal is about 3/5 of the way across the baffle. That looks closer to 9/10ths.

2) The framing does not look tough enough. Think of this: the framing has to be rigid enough to stop all vibrations, and prevent them from getting through to the baffle, floor, wall, ceiling, or anything else. Once again, on the other thread you can see how beefy the soffit framing is.

3) The actual soffit section, where the speaker resides, is too small. There's no room at all to put a decent amount of insulation around the speaker enclosure box, to damp any resonances going on in there, and considering that the space is so small, the resonance will be fairly high up the spectrum. Here, too, that thread is a good reference for the size of the soffit space around the speaker.

4)
I'll build the silencer box for air duct in the other room...
I'm sure you will build the silencer box for the OUTER leaf in the other room, but the silencer for the INNER leaf needs to be in this room.

5) The baffle goes all the way to the floor: it should not. There needs to be a fairly large space at the bottom, so that the hangers are well exsposed to the sound in the room.

6) What type of wood did you use for the hangers? That does not look like Homosote.

7) Are you sure that your speakers will end up at the correct height? That shelf looks to be at a strange height...

8 ) You seem to be going way too fast... I know you are in a hurry, but rushing a studio is not a good idea. There are better ways to have a room that appears finished to the untrained eye, to pass observation, but that can be easily stripped down and rebuilt later.

- Stuart -
matt-korban
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Re: Soft Flush mount specs

Post by matt-korban »

The speakers seem to be very close to the inner-edge of the soffit baffle. Yes, they should be offset a little, but that's more than "a little". Ideal is about 3/5 of the way across the baffle. That looks closer to 9/10ths.
The baffle is large 142cm. I have the center of the speaker at 85cm... If i move it, i have to recalculate my RFZ... I really need to move it?
The framing does not look tough enough. Think of this: the framing has to be rigid enough to stop all vibrations, and prevent them from getting through to the baffle, floor, wall, ceiling, or anything else. Once again, on the other thread you can see how beefy the soffit framing is.
Can you link me this thread? Guys, i can strengthen the frame, but trust me... it don't move now, don't creaks, don't vibrate, don't flexes for nothing! But, if you think that i have to do, i can strengthen more...
The actual soffit section, where the speaker resides, is too small. There's no room at all to put a decent amount of insulation around the speaker enclosure box, to damp any resonances going on in there, and considering that the space is so small, the resonance will be fairly high up the spectrum. Here, too, that thread is a good reference for the size of the soffit space around the speaker.
Now i can't move the soffit! It's large 75cm and heigh 45... The speakers are 38Hx31Wx19D.

I'm sure you will build the silencer box for the OUTER leaf in the other room, but the silencer for the INNER leaf needs to be in this room.
Ok we'll think soon about it.

The baffle goes all the way to the floor: it should not. There needs to be a fairly large space at the bottom, so that the hangers are well exsposed to the sound in the room.
I have 30cm from the floor to the baffle start point, like the John's design!
Under speaker 4.jpg
What type of wood did you use for the hangers? That does not look like Homosote.
The center of the speaker coincide with my ear height when i'm sitting (around 118cm).
You seem to be going way too fast... I know you are in a hurry, but rushing a studio is not a good idea. There are better ways to have a room that appears finished to the untrained eye, to pass observation, but that can be easily stripped down and rebuilt later.
Any idea?

Thanks for helping me guys!
Mattia.
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Re: Soft Flush mount specs

Post by Soundman2020 »

Can you link me this thread?
Sure!

thread on building and tuning a control room

thread about Steve's high-end control room in New Orleans

In both of those you can see how soffits are normally built.
it don't move now, don't creaks, don't vibrate, don't flexes for nothing!
Have you tested it with a speakers mounted in there, playing loud bass-heavy music? Touch the framing gently with your fingertips to see if you can feel the vibration. Also, once you have the front baffle on, there will be large changes in air pressure inside the soffit, trying to cause the baffle to vibrate... So you need to minimize the "unsupported area" of the baffle: no large spaces without framing behind.
Now i can't move the soffit! It's large 75cm and heigh 45... The speakers are 38Hx31Wx19D.
Which is why you should design everything about your studio very carefully before you start building... Take a look at those threads, to see how it should be.
I have 30cm from the floor to the baffle start point, like the John's design!
OK, that's fine: I was looking at the earlier version of the design.
The center of the speaker coincide with my ear height when i'm sitting (around 118cm).
It's the acoustic AXIS of the speaker that should be at ear height, or slightly above. Not the center of the speaker. Check with the manufacturer of your speaker to find out where the acoustic axis is on your speakers. It is better to have that a few cm above ear height, to help reduce reflections and comb filtering from the desk/console surface.
Any idea?
Take a look at this room:
Inside-out-ceiling-10.jpg
The soffits look finished, right? But not really. To pass final inspection by the money lenders, his soffits were nowhere near ready a couple of days before, so he just put black fabric over the entire soffit, with the speakers poking out. That's when the photo was taken: it passed inspection, then he took the fabric off again, took everything out of the soffit, and rebuilt it properly.


- Stuart -
matt-korban
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Re: Soft Flush mount specs

Post by matt-korban »

Thanks for the links!

Have you tested it with a speakers mounted in there, playing loud bass-heavy music? Touch the framing gently with your fingertips to see if you can feel the vibration. Also, once you have the front baffle on, there will be large changes in air pressure inside the soffit, trying to cause the baffle to vibrate... So you need to minimize the "unsupported area" of the baffle: no large spaces without framing behind.
Ok, i can do a test, and maybe a frame reinforcement.

Which is why you should design everything about your studio very carefully before you start building... Take a look at those threads, to see how it should be.
I completely agree with you, but i have received an answer for financing only 4 month ago, with the end only in 10th February! (really a :cen: )
The soffits look finished, right? But not really. To pass final inspection by the money lenders, his soffits were nowhere near ready a couple of days before, so he just put black fabric over the entire soffit, with the speakers poking out. That's when the photo was taken: it passed inspection, then he took the fabric off again, took everything out of the soffit, and rebuilt it properly.
Ok! Maybe i can do same thing!

Do you think i can close the front center baffle with Drywall?
And, can i use MDF only around the speaker hole, and double layer of drywall in all the rest of soffit? (baffle, "wings left and right", upper, and center)
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