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 Post subject: Re: Soffit mounting?
PostPosted: Wed Mar 23, 2011 7:32 am 
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OK thanks,

... and this will not have a negative impact on the function of the hanger compartment?

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 Post subject: Re: Soffit mounting?
PostPosted: Wed Mar 23, 2011 9:15 am 
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You don't need the chicken wire where the hangars are: its only real purpose is to keep the insulation from closing off the airflow: it's just a shape to hold the insulation in place, and leave that "duct" for the cooling air. You only need it where you have insulation. The hangers already have enough airflow between them.

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 Post subject: Re: Soffit mounting?
PostPosted: Fri Mar 25, 2011 4:09 am 
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I don't want to start a new thread for this, so..

Has anyone tried soffit mounting Focal Twin 6's?

Those are going to be my monitoring solution in conjunction with the Sub 6, and I have some doubts about soffit mounting them.. However, if anyone here has better info, I'd be more than glad to hear it.

Thanks!

- Funk


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 Post subject: Re: Soffit mounting?
PostPosted: Fri Mar 25, 2011 4:23 am 
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Funktion wrote:
I don't want to start a new thread for this, so..

Why? The thread title is clearly generic soffit mounting, and you are asking about one specific model.

Andre

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 Post subject: Re: Soffit mounting?
PostPosted: Fri Mar 25, 2011 4:36 am 
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AVare wrote:
Funktion wrote:
I don't want to start a new thread for this, so..

Why? The thread title is clearly generic soffit mounting, and you are asking about one specific model.

Andre


Allright, sorry..

I browsed through the topic and noticed quite a few questions about specific speakers so I thought I'd put the question here.

I'm new on the forum, so I don't yet know if it is better to start a new topic or just use an existing general topic where people have also ventured into specific models.

But I'll start the topic then if this thread isn't suitable.

EDIT: The topic is up. viewtopic.php?f=12&t=15780


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 Post subject: Re: Soffit mounting?
PostPosted: Thu May 24, 2012 7:35 am 
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Hey guys,

So I have a question regarding soffit mounting. My monitors will go in a mdf box mounted on top of a brick pillar. I will use 50mm pvc pipe to vent air in and out as per Johns design because the monitors are active.

I have two questions. Is it ok to build the entire thing as a superchunk? Just stack the insulation right through top to bottom of the corner. Or should I superchunk the top (above speaker box) and make hangers for the bottom (below speaker), is there a difference?

The second question is about the face of the soffit. I seem to be misunderstanding how it works. If I read this thread and all the talk about how they used to put speakers in the ground to test them that makes me think the face should be a solid material ie drywall board or MDF? I understand the thinking in making the bottom an absorbent trap as it is below the "desk line" so then do I make the section above that (around the speaker) with a solid face or is this also just fabric over the insulation?

Thanks

G


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 Post subject: Re: Soffit mounting?
PostPosted: Thu May 24, 2012 10:19 am 
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Quote:
I seem to be misunderstanding how it works.
:)
The front panel of the soffit should be as large as you can possibly make it: Floor to ceiling and as wide as will fit across the diagonal. It is trying to be an "infinite baffle", so if needs to be "infinite": OK, so "infinite" is a bit hard to do, but your should at least aim for "very large". And it all needs to be massive, heavy, rigid and thick: It needs to be unmovable. Some folks use a few layers of wood, others have been known to use brick and concrete.

Yes, the bottom part of the front panel can be covered with absorption, but it isn't a superchunk : it's just a layer of absorption on the front of the panel, below the level of the desk. And yes you can put hangers inside the bottom part, BEHIND the front panel. In other words, the go inside the cavity under the shelf that holds the speaker, in which case that bottom part must be separated from the top part: the hangers are not inside the same space as the speaker, but rather in a separate cavity, below it. If you do that "hangers in the bottom" thing then don't take the front panel all the way to the floor. Leave a gap of about 15cm across the full width of the soffit at floor level. In other words, there is an empty space right at the bottom, and the soffit panel only starts 15 cm above the floor, then continues all the way up to the ceiling. So there is no superchunk above the speaker either. If you really wanted to you could stop the panel a bit short of the ceiling and put a small bass trap in there, but you cannot use the cavity where the speaker itself is, since that is part of the soffit.

Quote:
So I have a question regarding soffit mounting. My monitors will go in a mdf box mounted on top of a brick pillar.
I would suggest keeping the brick pillar but replacing the "box" with a proper soffit. MDF is fine for the front panel, but make it very thick.

Quote:
I will use 50mm pvc pipe to vent air in and out as per Johns design because the monitors are active.
You could do that, but 50mm doesn't provide a lot of cross section for cooling. A common way of doing the vent shaft is to just fashion a rectangular shape out some chicken wire, so you can make it as large as needed for good ventilation. The vent shaft doesn't need to be super strong: chicken wire is fine. It is just there to keep the insulation from blocking the shaft.

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so then do I make the section above that (around the speaker) with a solid face or is this also just fabric over the insulation?
Very, very solid face, and definitely not "fabric over insulation". You could cover the
Quote:
panel
with fabric if you want, for aesthetics, but the panel still needs to be large, thick, rigid and massive.

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 Post subject: Re: Soffit mounting?
PostPosted: Thu May 24, 2012 5:41 pm 
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Hey again Stuart,

Thanks I am understanding it alot better now! Just a couple things quickly...

Quote:
I would suggest keeping the brick pillar but replacing the "box" with a proper soffit. MDF is fine for the front panel, but make it very thick.


If I understand correctly, this is what i must do. Brick pillar with shelf on top (shelf to fill the entire footprint of the soffit but without touching/coupling to the front panel) - speaker on top of the shelf. Second shelf above the speaker - insulation above the second shelf.

So essentially the "soffit" is an empty cavity? assides from the hangers underneath the shelf? And possibly insulation above the speaker? I originally thought the entire thing must be packed full of insulation (hence the superchunk question)

Will 32mm MDF be ok for the front? Or should I maybe look into making it a single brick wall with a 16mm MDF board on the front (MDF purely to make it easier to neaten up the hole)

Im thinking I will use 100mm flexable ducting for the airflow instead of chicken wire, purely because I allready have some I can use.

Thanks man, your helping me so much with this build!

G


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 Post subject: Re: Soffit mounting?
PostPosted: Tue May 29, 2012 12:49 pm 
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Quote:
If I understand correctly, this is what i must do. Brick pillar with shelf on top (shelf to fill the entire footprint of the soffit but without touching/coupling to the front panel) - speaker on top of the shelf. Second shelf above the speaker - insulation above the second shelf.
All fine, except for the second shelf: skip that. Not needed. The entire top section is one single cavity, right up to the lid, and all of it is filled with all your scraps of left-over insulation. The speaker itself is often housed in a box, with rubber all around the inside to completely isolate the speaker from the box. If your speakers are active (built-in amplifiers) then you also need to cut large slots in the top and bottom of that box, for ventilation, and make the chicken wire mesh "chimney" inside the cavity, leading up to a slot in the front panel of the soffit. That's to prevent the insulation from blocking the ventilation path. so there's a clear path right through the soffit for air to flow past the back of the speaker and keep it cool.

Quote:
So essentially the "soffit" is an empty cavity?
Well, two cavities: the bottom part has the hangers in it, and the top part is stuffed with leftover insulation, dirty washing, old carpets, pillows, mattresses, bodies, etc. :) (Joking! Just insulation).

Quote:
I originally thought the entire thing must be packed full of insulation
It is, but it's not a superchunk since the insulation is not exposed to the room at all: its just there to damp the cavity. It is surrounded on all sides by MDF, plywood, drywall, etc. If there were no front panel on the soffit, then it would be a superchunk. But then it would not be a soffit! :)

Quote:
Will 32mm MDF be ok for the front?
That would be fine.

Quote:
Im thinking I will use 100mm flexable ducting for the airflow instead of chicken wire, purely because I allready have some I can use.
As long as it is big enough to cover the entire slot on the top of the speaker box, and has a large enough cross section to provide good air flow, that would be fine.

Quote:
Thanks man, your helping me so much with this build!
:) :oops: :!:


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 Post subject: Re: Soffit mounting?
PostPosted: Tue Jun 05, 2012 6:37 am 
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Hey Stuart,

Thanks man. That pretty much solves all the confusion I had about soffits. I think I can build em pretty good now. Basically going to build them exactly as discussed then. Just one more question....

Can the speaker box be made of fabric? What I originally did was build a wooded frame and covered it in fabric, as opposed to building a solid box around the speaker. I mean the purpose of the box is purely to keep the insulation and the speaker apart is it not?

So ill take out the top shelf in my design and put hangers in the bottom cavity.

Thanks again mate

G


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 Post subject: Re: Soffit mounting?
PostPosted: Fri Jun 08, 2012 6:14 pm 
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SoundBoy wrote:
Hey guys,
Is it ok to build the entire thing as a superchunk? Just stack the insulation right through top to bottom of the corner. Or should I superchunk the top (above speaker box) and make hangers for the bottom (below speaker), is there a difference?


I'm not sure if the answers given directly answer this question...because I have the same one, and I still don't know. I know that John's soffit design that has been posted in this thread numerous times shows hangers.. BUT, what I want to know is what is the point of hangers instead of just filling the cavity with insulation? Seems like an extra complication when enough insulation will absorb anything that the hangers would.

Also, what is the point of building a box around the speaker? I remember Barefoot commenting in old threads about soffit mounting that there is no reason to build a box around a speaker, and in fact, a regular stand is fine. As long as the stand and speaker are decoupled from the front wall. Seems like another unnecessary complication.

Also, I don't see a point either for separating the sections of the soffit cavity or leaving a gap at the bottom of the soffit wall.

I've read this entire thread and many others and don't understand why a speaker on a stand with a wall in front of it with a properly cut hole for the speaker, filled with a bunch of insulation wouldn't be as good as any other soffit design.. at least for a passive speaker that doesn't need to have any kind of air circulation to keep its amps cool.

OH, and here is a question. I am putting the mains up above the sight path of the nearfields, and I need to angle my soffit down so that the speakers point at my head of course. I was thinking a cool design would be to just continue the angle of the soffit wall all the way down to the floor. In this design, I end up with less cavity volume on the bottom of course. As opposed to angling the soffits and then straightening it out about half way down. (so that the soffit is at a 90 degree angle to the floor) this way I of course end up with more cavity space on bottom. Anyone have an opinion on if my first idea is an acceptable design and will work as well as the second way?


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 Post subject: Re: Soffit mounting?
PostPosted: Wed Nov 28, 2012 2:09 pm 
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I'm in the same boat as my friend above with one twist: I'm actually building the speaker cabinets to house my 15" tannoy HPDs. By the time I'm done, my very large cabinets will be almost floor to ceiling. I have the opportunity to do the box within a box design when I build the cabinets, so my plan is to mount them on a cinderblock wall, and make sure the cavity is insulated all around it. Obviously I'll also take great care that the front baffle of my cabinet is not coupled to the front wall.

Has anyone ever tried to soffit mount very large speakers like that? If I don't have room for hangers under the speaker (I probably won't), will that really make a difference? Any advice?

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 Post subject: Re:
PostPosted: Sun Dec 02, 2012 3:07 am 
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barefoot wrote:
The reason I believe some recording engineers don't like soffit mounting is because it's often done improperly. The most critical aspect of soffit mounting is making sure the monitors are properly designed to work in such an application. Most nearfields and a good deal of midfields are not.

I have a pair of KRK RooKit5 (yes, budget-speakers)
What could I expect regarding soffit-mounting them?

Oh, and I'm mixing up Suffit with Flush. What's the difference?
Edit: Ok, it's the same :)

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 Post subject: Re: Soffit mounting?
PostPosted: Sat Dec 08, 2012 10:42 am 
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Yep, soffit mount and flush mount is the same thing. "Flush mount" is actually more correct, technically, but "soffit mount" seems to have become the de-facto standard way of talking about it.

Quote:
I have a pair of KRK RooKit5 (yes, budget-speakers)
What could I expect regarding soffit-mounting them?
Soffits fix the same problems for all speakers: There is a major problem with speakers that are not soffit mounted: the sound wraps around behind them, bounces off the front wall, and interact with itself in various ways. Soffit mounting eliminates all of that: It also improves the bass response, and eliminates the power imbalance inherent to all small speakers. The only issue with the Rokit 5 is that it does not have a bass roll-off control on the rear panel, so you will have to roll that off manually, with an external cross-over or parametric equalizer. If you do that, then your speakers should sound good when sosfit mounted.

- Stuart -

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 Post subject: Re: Soffit mounting?
PostPosted: Sat Dec 08, 2012 6:23 pm 
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Soundman2020 wrote:
Quote:
I have a pair of KRK RooKit5 (yes, budget-speakers)
What could I expect regarding soffit-mounting them?
Soffits fix the same problems for all speakers: There is a major problem with speakers that are not soffit mounted: the sound wraps around behind them, bounces off the front wall, and interact with itself in various ways. Soffit mounting eliminates all of that: It also improves the bass response, and eliminates the power imbalance inherent to all small speakers. The only issue with the Rokit 5 is that it does not have a bass roll-off control on the rear panel, so you will have to roll that off manually, with an external cross-over or parametric equalizer. If you do that, then your speakers should sound good when sosfit mounted.

Thanks Stuart!
Well, anyway it seems logical for me to design my studio for some new speakers.
Buying or making an extra box for just the bass roll-off is probably not gonna be on my priority-list :)

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