Soffit mounting?

Yes thank you, that clears it up completelly

oops. sorry, I though you were asking about the gap in the separation plate. sideshow has it correct.

Hi! This is my first time posting, although I've been lurkyng the forum for quite some time now! Anyway, to the point. I realised that problems can arise when soffiting ported speaker designs wich have the bass reflex port on the back of the speaker (suck as the new Genelecs). Any thoughts on this? Cheers!

since you're going to get a bass boost due to the soffit mounting, the bass port in the back might not matter. unfortunately unless someone has done it or the manufacturer has details, its a matter of trial and error...

Can you cover the ports with a light fabric such as Muslin? Or should they be left completely open? I alomost wonder if small quiet computer fans could be installed in the bottom ports to pull the hot air out? Or maybe in the top port to draw cool air in?

if you check on the SAE site, you'll find a drawing for the soffit mounting which incudes an air port to allow air flow to move heat and let the port function.

gullfo wrote:

if you check on the SAE site, you'll find a drawing for the soffit mounting which incudes an air port to allow air flow to move heat and let the port function.

this looks like the top is open and the bottom vent is covered in fabric: looks like the bottom is open but no vent at the top:

My design has an open back for the speaker. Meaning the box has a bottom, top and two sides only. The back of the box is open. I have a port cut above the speaker, in the wall, to allow heat to escape and a small port at the bottom of the wall and just to the left of the speaker. The speakers are sitting on top of concrete blocks cemented in place, completely detached from the wall.

check on the construction forum - there's a number of folks who have built soffits which are open enough for rear ported speakers - Kendale, Djo, Giles, etc... on the top soffit drawing though, the cloth is acoustically transparent to allow sound in - and air. so this design should work. you could modify to make the entire open back to get more flow.

[size=12]Hi . Sound good, around here. Ok, now I know a little more and I'm ready to deal with "soffit" ! Almost ready to start designing it, but still have questions: 1- I hesitate between the 60° or 90°, as I wonder if the 60° is not a little better for a person sitting behind point 0. ....... 2- the second question is: In witch angle would you place the hangers in the bass traps bellow the speaker corner ? (See joined image for details.) And also, how many and how close should they be to be effective enough in the space i can give them. If the box becomes too deep, my seat moves further back in the room, and it's getting close to "forbiden zone" (?!?!) John, we can only trust your stoffit drawing, but it would be so great to have a top view of it ! Please help ! I live in France, good for wine, but for sound .... help !!

option 1 or 3 for the traps. for the monitor angles, even though the general rule is 30 degrees, if the speakers need to be 45, or 38, or 26, or 22.5, then thats what they need to be... a long control room tends to benefit from the speakers having less of an angle, and actually, in general, positioning the speakers so that you get a proper image (whether stereo, 5.1 etc) is important, and having the speakers "flatter" may be the answer regardless of room length.

Thanks, Gullfo. For the hangers, I 'll then choose option 3; 3 is the number, the number shall be 3 ! ..................................................... <<...having the speakers "flatter"...>> that's not french anymore.....:wink: sorry , my english-french dictionary does mention speakers situations.!.. ....I know how to flatter singers, but speakers ..? How do you do that ?

Flatter=less of an angle. To quote Glenn " and having the speakers "flatter",>> or with less of an angle<<, may be the answer regardless of room length.

nyves wrote:

<<...having the speakers "flatter"...>> that's not french anymore.....:wink:

its not even good english :-) xspace has it correct - i meant to say "flattening" the speaker angle may be needed, or making it "steeper" - all depends on how well the phantom image is supported with the speaker layout... i've seen some studios (even a big-name one recently ;-)) where the monitors were practically sitting side-by-side behind the console because it gave the engineer the correct imaging. for some reason, no matter how nice the soffits, it all ends up with NS10's on the console bridge :shock:

for some reason, no matter how nice the soffits, it all ends up with NS10's on the console bridge

:D - actually there is a reason for that. Nearfield mixing is easier on the ears over time but you still need a good soffit system to check the low end as NS10 roll off at 100hz. A nice combination I had once in a studio was NS10s nearfield, NS1000s soffit mounted.

for some reason, no matter how nice the soffits, it all ends up with NS10's on the console bridge

Oh yeah !

Nearfield mixing is easier on the ears over time but you still need a good soffit system to check the low end

yesss, man ! More than that, the thing you like to have is: as many listening options as possible. Multi-media with woofer, headphones.. even a combo bass amp, can show a usefull image. I did wire every room of the house 1-to the kitchen's radio box 2-to the living room 's B&O. 3-to the kid's bedroom panasonic blaster. ..and the best of all: 4- i have a looong stereo jack, hanging at the door, ready to crawl out to the car, outside in the street. Well then, why not add the benefits of the soffits to all that. The hard thing about it , is to built it in a way you can still slightly change the speaker positions until you find the right one, Same need of flexibility for the depth of the bass trap. Hard to figure out before trying and measuring, changing, re-measuring... and foruming ! More flexible solution would be something like that http://www.silentsource.com/basstraps-tubetraps.html What do you say ? ...................... Question about Yamaha : Would you consider the MSP10 as correct speakers to soffit ?

Hi I'm a new member, trying to read as much as I can. But I can't seem to figure out what the difference between suffit and flush mounted monitors is?

Jannik Gade wrote:

I can't seem to figure out what the difference between suffit and flush mounted monitors is?

That reminds me of a Simpson's episode when Homer tries to build a robot. He says, "why doesn't it work?" Marge says "remember the robot at the theme park, how it had all that 'stuff' inside it?" "Doh!"

Sorry english isn't my primary language :( When I look at these pics the only main diffrences I see is the angle and the airflow passage both said to be optional further more a reply like that dose'nt really help at all..

Sorry for wasting your time! I was bored waiting for the experts to reply to my thread. It was just an image that came to mind. I can not tell you what the dif between flush a soffit mounting is? I don't even know what soffit means? I looked it up in the dictionary and it had a pic of Homer!!! No, seriously....I think it is an "acronym"?

Jannik Gade wrote:

Hi I'm a new member, trying to read as much as I can. But I can't seem to figure out what the difference between suffit and flush mounted monitors is?

quote=John Sayers]...soffit mounting is where you install the speakers in the wall so the front of the speakers is flush to the wall. It eliminates the speaker radiating in 360 degrees in the low frequencies./quote It's the same thing. :)

yes, flush and suffit are the same thing. Different word. Just like Gypsum is the same as Drywall. The first pic you linked has an airflow behind the speaker to release the heat if ye speakers are active (build in amp). If they're passive you might wanna close it 100%. I'd advise to check the "speaking of speakers" forum part and follow the stickies...

I have a few more questions about the soffit design: 1. Why do the monitors need to be angled if the base height is greater than 48"? (Is 48" the average seated ear height? If so, why measure from the base of the monitor instead of the acoustical center?) 2. Is the angle calculated in each case using finished height and listening distance? (Where exactly are you aiming them? At 38% from front wall and 48" high? or would imaging be helped by aiming them slightly farther and lower? And are these calculations derived from the base of the monitor or the acoustical center?) 3. Is there an optimum monitor height given front wall height? (I think I had read that it is 50% wall height but now I can't find it) 4. Why doesn't the hard soffit face (as an extension of the front baffle) extend down from the monitor at the same approximate distance as the top and sides? (I'm just trying to understand the concepts. Is it that the emanating waves would hit the back of the console or is it a matter of percentage of the overall surface of the soffit to be used for different purposes - bass trap, high freq absorb, reflective. Or am I totally misunderstanding the drawings.)

you want the acoustic center of the monitor to be aimed at the listening position. if the baffle mounted speaker is in the right position, then you don't need to angle it. if its too far above the ear level, then you'll need to angle it down. this can also be useful when you need to put the monitors above a window or have a lot of equipment on the console desk. optimal height for the monitor would not be @ 50% of the room height - 38-42% is better... the extension below (and behind the absorption) is the rear baffle plate which goes down to the level of the entry port. you're making some trade-offs in terms of potential diffraction caused by the lower edge transition vs. reflections off the console desk.

Thanks Gullfo. Another question I have relates more to room layout in re the speaker angles. I am having a problem understanding where the splay is angled from. Concerning the 90* it was stated that an acceptable splay would be 22.5* and for the 60* at 12*. Now my question is: Are the opposing rt and lt walls splayed from each other or from the square? 60* speaker angle example: |6*/ (12*) \6*| or |12*/ (24*) \12*| 90* speaker angle example: |11.25*/ (22.5*) \11.25*| or |22.5*/ (45*) \22.5*| Sorry if this is kind of unclear. I don't have access to SKP on this machine.

The attachment is from the NARAS (AKA Grammy) surround sound recommendations. It is for the 60° speaker setup. I hope this helps. Andre