Soffit mount my Genelecs 1031A. Different soffit design

Hi eveybody, i´m new in this forum so first of all some words about myself :D My name is norman, i´m making music since several years and finished my studies at the SAE Frankurt last year. So there´s already some acoustic knowledge ;) I now rent a room for my equipment (Mackie 32/8 + Expander, FF Saffire 26 I/O + Red 3, SPL Dynamaxx, Lexicon MX400, Genelec 7050 Sub, Patchbays, Midiexpander, FX and many more…) and want to soffit mount my Genelec 1031A. The dimensions of my room are not the best concerning the golden ratio, bornello etc. (H: 266 cm, W: 282 cm, D: 554 cm) but maybe there´s a good compromise. The walls are all gypsum I think and the ceiling is already hung down. Furthermore there´s a carpet on the whole ground (see the first Picture). I already tried to figure out with somebody, where my G´s have to be placed (see second picture). We came to the conclusion, that the walls can be straight. Furthermore i read in this forum, that you can differ from the stereo angle of 30° in small rooms like mine. So what angle would you suggest? What else should I keep in mind for the right placement and angle of the speakers and the wall? I looked up the pictures of johns and the SAE´s soffit design and they are completely different to the design of the acoustician I was talking to. He mostly builds the whole frame for the walls and monitors out of wood, the front with gypsum boards, and then fills the empty space behind with ISOFLOC. In this case of course the amplifiers are removed from the chassis. Has anyone made experiences with Isofloc? If so, what kind of wood would be the best for the frame and are to coats of gypsum board enough? Sadly I didn´t find much useful articles or sites on the internet so I would appreciate if someone could help me. Thank you. normanbeats

Isofloc reads like it is insulation made of recycled material. http://www.daemmprofi.de/gb/4unternehm-gb.html If this is your product, the best results for placement control in a vertical cell will be to spray it in. It is a loose type insulation so it does not have an attached facing to install it with. But, I have read suggestions to take the unwrapped bails and stack those up as trapping.

Thanks for your reply xspace. Of course i know what isofloc is and how it is used but i never worked with it and i was wondering if anyone has made experiences with this kind of insulation for his control room an can give me some support who to build the wooden frame, the front etc. as i posted above. One of the most problems is that i couldn´t find any site on the internet where somebody used this kind of soffit design for his monitors :( So its very difficult to do it all by myself if i don´t get any advice and support. Please help me ;) Thanks norman

normanbeats wrote:

Thanks for your reply xspace. One of the most problems is that i couldn´t find any site on the internet where somebody used this kind of soffit design for his monitors :( So its very difficult to do it all by myself if i don´t get any advice and support. Please help me ;) Thanks norman

It's all right here....waiting for you to help yourself! Search for: soffit AND mount AND speakers

If you take a little more time reading this forum, you might stubmle uppon a little forum part called "speaking of speakers" which carries a bunch o' nice stickies about soffitmounting etc. Help yourself, read this filth ;) btw, soffitmounting nearfields ain't such great idea. It's not for fun they call those type of monitors "near"-fields. They work best within a close range of your ears.... but you should figure that out by reading stickies.. stick to that or I'll stick a stick up ye... ah, never mind :twisted: welcome to the forum :)

plus i'd opt for 30 degrees instead of 45 on the front baffles

Well, there are a lot of useful comments but i still couldn´t find any post about soffit mounting with isofloc. So i guess nobody of you has ever made experience with it? Maybe John? @gullfo: Do you mean like the pic below? Don´t you think in this case the sweet spot will be to far away from the monitors? Or would you keep the stereo base very small? Thank you

sorry, then i think of angles i'm thinking off the front plane - 30°, but its really a 60° triangle all told. that said, these are recommendations because you have to check the monitor dispersal patterns as well as deal with your room space, baffle extensions to support the speaker cutoff response, and other factors. if you check the Genelec site, they have some very nice documents related to baffle mounting their monitors, acoustic center diagrams, and even CAD (DWG) files for their products. on isofloc - if i'm reading it right is blown cellulose insulation. you'll need something to bundle it up a bit like mesh or the light open fabric used on upholstery work. the framing could be metal or wood - ~2x4 (50mm x 100mm) w/ 2x 16mm drywall. the baffles can be 25mm MDF or some other dense rigid wood.

thanks for all the replies. i just read a lot more about soffit mounting, speakers etc. in this forum and now i´m almost ready to start my build with johns design. Nevertheless there are some little questions left, so i still hope anyone can answer them... 1. the space above the Speaker box shall be filled loosely with insulation. In a post John wrote that this could be old cloth but can u also use mineral wool or would this stop the air flow? 2. what exactly is meant by "cloth Front"? Is this really just a piece of cloth like a thin carpet covering the front? 3. john wrote that the acoustic hangers are "wrapped in insulation". what kind of insulation shall be used here? Mineral wool again? 4. the front under the speaker shall be absorptive (especially for high frequencies reflected by the rack or console i think), so why is there a rigid insulation or 703? Thanks a lot for your held. Peace Norman

normanbeats wrote:

1. the space above the Speaker box shall be filled loosely with insulation. In a post John wrote that this could be old cloth but can u also use mineral wool or would this stop the air flow?

you could use pink insulation or mineral wool (supported to avoid blocking the opening) but it depends on your budget. the lightweight insulation is likely cheaper.

normanbeats wrote:

2. what exactly is meant by "cloth Front"? Is this really just a piece of cloth like a thin carpet covering the front?

you want cloth which breathes. not a carpet.

normanbeats wrote:

3. john wrote that the acoustic hangers are "wrapped in insulation". what kind of insulation shall be used here? Mineral wool again?

could be dacron, pink, or could be mineral wool.

normanbeats wrote:

4. the front under the speaker shall be absorptive (especially for high frequencies reflected by the rack or console i think), so why is there a rigid insulation or 703?

absorption on mids as well as highs to ensure balance.

Tahnks Gullfo, that makes it clear. I think i´m ready to start building now. Concerning the "carpet": Of course i ment curtain, not carpet :D Just mixed it up a little bit... Peace normanbeats