soffit or not?

Started by shimmer on 23 August 2017. 35 replies. In the Library under Speakers and soffits.

Originally posted at johnlsayers.com, topic 21191.

Hey guys, i was just wondering if any of you guys are not using soffit for speakers and getting good results? I ask this because I am looking to upgrade my speakers in a couple off years and soffit construction for my new to be build controlroom with current speakers would be a shame of the construction. and I see a lot of studios without them even the pro's thanks!
i was just wondering if any of you guys are not using soffit for speakers and getting good results?
It is certainly possible to use speakers that are not soffit mounted ("flush mounted"), as long as you are aware of the artifacts that such a setup will create, and provide the necessary treatment. For example, there will be large null in the frequency response caused by the front wall of the room, and the way it interacts with the sound that exists the rear of the speaker. That is often referred to as the "SBIR dip". If your room is large enough, you can deal with that by having your speakers at least 2m away from the front wall, and maybe as much as 3m if the speaker has very good low frequency extension. Or if the room is not big enough for that, then you would have to push them up right against the front wall, forcing the SBIR dip up high enough into the mod range that it can be dealt with by having suitable absorption on the front wall, directly behind the speaker. Etc. There are quite a few such issues, but they can be dealt with to a certain extent, if you design and build the treatment correctly.
I ask this because I am looking to upgrade my speakers in a couple off years and soffit construction for my new to be build controlroom with current speakers would be a shame of the construction.
Why? Just design the soffits such that the speakers can easily be removed and replace with other speakers, without needing to modify the soffit. That's what I did for this room, a few years back: viewtopic.php?f=2&t=20471 - Stuart - - Stuart -
holy shit! that rooms looks and must sound awesome! I saw the soffits, looks pretty awesome. any headsup on how to design those? any links on the forum where i can read up on the topic? thanks for your time. greets Nillis
holy shit! that rooms looks and must sound awesome!
Thanks for the kind words! :oops: It took a lot of work to get it that good, but I think it was worth it.
I saw the soffits, looks pretty awesome. any headsup on how to design those?
Originally they had Genelec 1031A's, but Rod (the owner) told me he would probably upgrade at some point, so I designed the soffits with easily removable "trays" that have the speakers mounted on them, and far larger than needed, even for very large speakers. When the time came to upgrade a couple of years later, and we decided on Eve Audio SC-407's, Rod simply built new trays, mounted the new speakers in them, and was able to switch them over in a very short period of time, with minimum downtime for the studio. We then spent many fun hours fine-tuning his room to get the maximum possible performance out of it and out of the speakers. I think the results speak for themselves! :)
any links on the forum where i can read up on the topic?
Afraid not. That's a proprietary design that I developed specifically for a paying customer, so I'm not at liberty to publish all the details. But I'm sure Rod won't mind me revealing the general concept: The soffits were designed to deal with some deficiencies in the room (shape, size, large desk with wing modules), so the speakers are raised a bit higher than I would normally put them, and angled down slightly (just a bit more than 4°), and that's what also produces the "eagle wing" effect. I designed the cloud to enhance that effect: the overall design motif is that the room looks a bit like an eagle in flight, based on a quote from the Bible. Since the room is designed on the basis of the RFZ concept, the "wings" of the soffits are angled more than the soffits themselves, such that all reflections at the front of the room are deflected past the mix position, leaving a central area around the head of the engineer that is totally free of early reflections. The only sound that arrives at the mix position is the pure, clean, unadulterated direct sound form the speakers, followed by a low level ambient reverberant field, suitably delayed by it's trip around the room, and suitably diffused, to give a bit of life to the room. All o that is kept neutral, of course, in both frequency and time domains, so the room absolutely meets (and beats!) the strictest international specs. It's about as flat as you could ever hop for in a high-end studio control room, as you can see from the acoustic response graphs. In the end, we applied a slight "house curve", very similar to old B&K curve that engineers like so much, winch very slightly boosts the low end, and very slightly rolls off the high end. That makes the room very pleasant for long hours of critical listening without running into ear fatigue. The mechanism for the removable trays and the internal speaker mounts is rather simple, but proprietary. All I can say is that there are internal elements inside the tray that allow the speaker to be aimed precisely, with very fine mechanical adjustment, and the speakers are also fully floated within the tray, such that they cannot possibly transmit any vibration into the soffit itself, mechanically. In other words, there's a tuned resilient system in there that supports the speakers without allowing them to touch any part of the soffit, and it is tuned such that the resonant frequency is way lower than the lowest frequency the speakers can produce. I wish I could tell you more about how that is done, but as I said it's partly a proprietary system that I developed especially for Rod, who is a paying customer, and I'm not sure that he wants all the amazing secrets of his room revealed! :) Suffice it to say, I have used a similar approach in a few other rooms, for other paying customers, and it works well there too... In any case, if you provide more details about your room, your current speakers, your expected future speakers, your goals, your budget, etc. I might be able to point you in the right direction so you can design your own soffits. This is not the only way to do it, but it's a really, really good way of doing it! - Stuart -
Soundman2020 wrote:
In any case, if you provide more details about your room, your current speakers, your expected future speakers, your goals, your budget, etc. I might be able to point you in the right direction so you can design your own soffits. This is not the only way to do it, but it's a really, really good way of doing it! - Stuart -
Hey Stuart that's verry kind off you! I attached a jpg of the inner leaf room size. The Height of the room is only 2,1 meters. But that is the maximum height I can achieve in my basement. Current speakers are Tannoy reveal, but for this room I'll be bying adam A7X. so soffit whill be for adam's A7X. future speakers after adam's?? don't know yet. but i woud like to keep my options open. But I don' t think i need extreme large speakers for a room this size. so... No need to build a collosal soffit. My Goal is to create a room that translates the mix from the speakers well to me. so I can improve my mixing skills and make the right judgement calls when it comes to mixing / instead of being drowned in reflections and low end rumbling.(wich is currently the case) . Also the room needs to shield my family from music my music making. Budget = between 5000 / 10000 euro for room build without treatment. Need more info? Thans upfron!
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Hey Stuart, I just posted an update on the position a size available for the soffit in my room. If you have the time you can take a look @ it and see what you think is possible here. Thanks upfront.
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Hey Stuart, here you can find a overal view of the controlroom idea. Red is soffit. Bleu is HVAC fresh air silencer box Turquoise is HVAC/ Airconditioner unit. Greets
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Hey Stuart, euhm... I've been reading about soffit mounting and it essentialy made me rethink/ question my whole front side of the room. I mean speker angle, listening position etc... now this raises a few question for me, so if anyone can help me find the awnser? deeply aprecieted! question 1: I read a lot about the 60 degrees speaker angle that it gives a bigger sweet spot for the highs when moving around on the desk, but i don' t have a big desks so no prob. now my speaker angle is 73 degrees. is this a problem?? question 2: I read the listening position should be 1/3 of the room length. Why? and if i make my speaker angle 60 degrees my listening position shifts more to the mid of the room. is this a problem? Question3: My plans are to soffit mont adam's A7X. Now i read that one should be carefull soffit mounting nearfield monitors beacause they need to be near the listener. is this true? or can i perfectly soffit mont the A7X's question4: What is rule of thumb for speaker placement angle and listening position within a room??? Thanks to anyone who can help me out. I added an alternative placement of 60 degrees. but i feel the 73° angle is better becuse of the listening distance to the speakers. in the 60° setup i'm to far away and might have to push my speakers to hard. getting confused here.
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euhm... I've been reading about soffit mounting and it essentialy made me rethink/ question my whole front side of the room. I mean speker angle, listening position etc...
Great! If you have been researching it, and you are now confused, then that's a good sign! Because it is confusing, and in addition there's a lot of terrible advice floating around the internet than can confuse you even more, and lead you astray... So let's try to work through the myths and snake-oil, and get down to reality...
I read a lot about the 60 degrees speaker angle that it gives a bigger sweet spot for the highs when moving around on the desk
Speakers and angles alone do not create the sweet spot: The entire room design does. First, the speaker: The off-axis and on-axis response of YOUR speakers is the starting point for figuring out where the sweet spot can potentially be. It's simple math (or rather, simply geometry). If the dispersion angle of your speaker is, for example, 20° then obviously your sweet spot can be no wider than that! Depending on how far away from the speaker you are, that would tell you the actual possible width, in cm, for the sweet spot. Because as soon as you get outside the region of the speaker "dispersion" that still has flat response across the entire spectrum, you no longer have a usable response. You can plot this on a piece of paper: draw a triangle with the same dispersion angle as your speakers, then measure out the distance form the speakers to your ears (scaled, obviously), and measure the width of the tiriangle at that point. That's the MAXIMUM size that your sweet spot can be. So that's the first issue: find out what the dispersion angle is for YOUR speakers. Most good studio monitors have wide dispersion angles, so this is probably not an issue, but you MUST check to make sure. Some excellent speakers are still flat out to 40°, others don't even make it to 30°. When I design a room for a customer, I start with the speakers for this very reason. I need to know where the sound is going to go at what frequency, and how smooth the distribution is, so I can design the room around that.
but i don' t have a big desks so no prob.
Then you probably don't need a broad sweet spot! :) You might still want one, but you don't need one.... As long as the sweet spot is wide enough to cover the full area where your head will be while you are working, that's all you need.
now my speaker angle is 73 degrees.
You mean the axis intercept angle, right? 73° intercept implies that each of your speakers is toed in 36.5°, and therefore they must be spread a bit further apart than for a typical 60° setup. That's fine, as long as you understand what it will do to your sound-stage, as well as your sweet spot. Common confusion: sweet-spot is not sound-stage. Two different things. The sweet spot is the place in the room where you can hear the sound evenly (good frequency response, smooth decay times, good balance between left and right speakers, good phantom center, etc.) The sound stage is how the stereo image is laid out in front of you, left to right: do all the instruments sound like they are tightly bunched up all together in the middle, or do they sound like they are spread out widely across the room in front of you, some on the left, some on the right, some in the middle? You can sit in a nice sweet spot and have a terrible sound stage, or you can have a nice sweet spot and a broad sound stage. But you can't have a good sound-stage if you are way outside the sweet spot. To get a better idea of how this works, think o the extremes: First imagine that you have both of your speakers pushed together in the middle of the room, directly in front of you. You can have a nice sweet spot like that, but very poor stereo image: it will sound like all of the instruments are in pretty much the exact same location, piled on top of each other in front of you, with nothing out to the sides, because both of your ears are hearing almost exactly the same thing. Now imagine the opposite extreme: that you move the speakers out directly against the walls to your left and right, in line with your ears, and rotated 90° so they point exactly at your head. You will have an "amazing" stereo image like that, with all the instruments spread out very widely, because each ear is hearing pretty much only the speaker on its own side. However, it will sound unnaturally wide, and not very convincing, since your left ear hears almost nothing that is coming from the right speaker, and vice versa. Your head itself blocks most of the sound. So your brain can't use it's normal tricks of sensing the timing difference and level difference and phase difference between the SAME sound arriving at BOTH ears, to determine directionality, so the stereo image will sound "flat", with no "depth" to it. It will sound like it is all along a piece of string that goes through your head, but NOT in front of you. So clearly, you want something in between these two extremes. You do want your left ear to hear some of the stuff coming from the right speaker, without being completely in the "shadow" of your head, and vice versa. So you do want the speakers to be angled less than about 60°, absolute maximum, such that your left ear really can "see" some of the sound form the right, etc. But you also don't want them too close together, so that both ears hear roughly the same thing, so you want the angle to be more than about 15°, absolute minimum. Hence, the textbook recommendation for 30° angle: It's mathematically the "best", in theory. Both ears get to "see" both speakers, and the angles are optimal for good stereo imaging. But what happens if you make that 31° or 29°, instead of 30°? Well, basically nothing happens! You are no longer at the theoretical perfect point, but the offset is so minor that it makes no audible difference at all. If you check the mathematics, the cosine of 30° is 0.866, and the cosine of 31° is 0.857. That's a difference of just barely 1%. I terms of decibels, that means that one of your ears is now hearing the opposite speaker exactly 0.0432 dB quieter. Since the absolutely minimum change in intensity that people can hear is about 1 dB, and this change is just 4/100ths of a dB, clearly you won't hear any difference at all. OK, so how about if we go to 40° and 20°, instead of 31 and 29? Well, the cosine of 40° is 0.766, which is now a change of (1-(0.766/0.866)*100) = 11.5%, and that's a change of 1 dB, so it is audible, but only just. And at 20°, the cosine is .939, so the change is 8.5%, just a bit less than 1 dB. And if we go up to 50°? Cos(50°) = 0.642, which is a difference of 28.5%, which is 1.5 dB, so definitely audible. Thus, you should try to keep your angles with a reasonable range, of about 45° maximum and maybe 20° minimum, realizing that the higher the angle is, the wider the sound-stage is, but the flatter as well. Those are individual speaker angles, so the intercept will be twice that: this, an intercept between about 90° max and 40° min is probably OK for most rooms. So you 73° intercept should be OK. Personally, I try to keep intercept a bit tighter than that, around 75° down to about 50°. OK, but now for the kicker: most o the "text-book" diagrams state emphatically that it absolutely must be 30.0000000° on the dot, also then show that they want that apex of that perfect equilateral triangle to be smack bang in the center of your head! And if you do that, then the speaker axes are aligned perfectly... with your EYEBALLS! but not your ears.... I never have figured that out.... why would you want the speakers aimed at your eyes? You don't hear with your eyeballs! If your eyes are on-axis to the speaker, then your ears are obviously NOT on axis! :shock: Yet, that's what the diagrams show, and the text books recommend... Hmmmm... go figure.... So it simply makes sense to adjust the speaker angles, and the listening position, and the speaker locations, such that the speakers are aiming at your EARS, not your eyes. In fact, it seems the best setup is when the speaker axis grazes just past the tip of your ear-lobe, and therefore the point where the axes intercept will be many cm behind your head, not inside the middle of your head.
I read the listening position should be 1/3 of the room length. Why?
Smart question! :thu: The actual "perfect" spot is supposedly 38% of room length, which is theoretically where the modal problems are least noticeable. Note that I didn't say there are no modal problems at 38%! They are still there, and might still be terribly bad if the room is not well treated, but that's the point where they are LESS bad. The WORST points are 25% and 50%, since those are where the quarter-wavelength and half-wavelength peaks and nulls are at their maximum intensities, which is why you should avoid the middle of the room, and the 1/4 length locations. That said, this is just a theoretical best spot in a perfectly rectangular room. It is not written in stone, and the Modal Correctness Police will not arrest you if you choose another location! It's a guide-line, a good starting point, nothing more than that. You will very likely find that there's a better spot just behind that, or just in front of it. I find that it's usually a bit in front of that "perfect" spot in most rooms. Hence, I suggest 1/3 (which is 33.333333%, to be exact! :) ), since it is easier to remember, and easier to visualize.
and if i make my speaker angle 60 degrees my listening position shifts more to the mid of the room. is this a problem?
If it goes too far back, then yes, that's a problem! I try to stay within about 31% to 45% of room depth. But do be careful! In a small room, if you have your head at 45% when it is above the console concentrating on mixing, but then you sit up straight and lean back a bit in your chair, your head will now be at 50%.... :)
My plans are to soffit mont adam's A7X.
:thu: Smart move! Good speakers, too.
Now i read that one should be carefull soffit mounting nearfield monitors beacause they need to be near the listener. is this true?
Nope! Not true at all... Because there's actually no such thing as a "near field" monitor! :) And you should NEVER listen in the "near field" anyway! Bold statement? Yep. But true. Here's why: The "near field" is a property of the ROOM, not the speaker. This comes from the book "Architectural Acoustics":
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That's pretty clear, isn't it? That's from a leading text book on acoustics, not on marketing hype, so it tells the truth about what "near field" actually means. If you say that a speaker is a "near field" speaker, then you are using pure marketing drivel, not actual technical term. As you'll note in that image above, it clearly says"Sound pressure levels can fluctuate dramatically in the near field .... sound pressures cancel and enhance each other near large reflective surfaces [such as a desk, console, etc.], so sound pressure level measurements should be avoided in the near field." I kind of think that's what our ears do: they make "sound pressure level measurements". So according to Architectural Acoustics, you should not try to listen in the "near field", since levels fluctuate, and pressure cancel each other out, or enhance each other... So why on earth would anyone make a "near field monitor", and tell you to listen in the "near field"? ??? Beats me...!!! Not convinced? Then maybe listen to what one of the world's leading experts on speakers says: I quote Floyd Toole himself: "In recording control rooms, it is common to place small loudspeakers on the meter bridge at the rear of the recording console. These are called near-field or close-field monitors because they are not far from the listeners. ... the near field of a small two-way loud-speaker ... extends to somewhere in the range 21 in. to almost 6 ft (0.53 to 1.8 m). Including the reflection from the console under the loudspeaker greatly extends that distance. There is no doubt, then, that the recording engineer is listening in the acoustical near field, and that what is heard will depend on where the ears are located in distance, as well as laterally and in height. The propagating wavefront has not stabilized, and as a result this is not a desirable sound field in which to do precision listening, but as they say, perhaps it is “good enough for rock-and-roll.” Your honor, I rest my case! As the man says: "this is not a desirable sound field in which to do precision listening". OK, maybe this calls for a more complete explanation: If you set up a speaker at one end of a large room and play music through it, that sound spreads out through the room, bouncing back and forth between the room boundaries and objects in the room. If you suddenly turn off the speaker, that sound continues to bounce around for a while, slowly dying away. How long that takes depends on several factors, but the point is that the sound does NOT stop instantly when you cut off the speaker: it carries on "reverberating" around the room. When the speaker is on, that "reverberation" is obviously still taking place, and still filling the entire room, along with the direct sound from the speaker. The sound that remains when you cut off the speaker is called the "reverberant field", and the level is more or less constant and even throughout the room (this is a large room that we are talking about). It doesn't matter where you are in the room, as soon as you cut the speaker off the remaining level is roughly the same all over, since it is just reflections that are bouncing around randomly. So with the speaker turned on, if you go all the way to the other end of the room to listen, as far away from the speaker as you can, then what you will hear is practically all "reverberant sound" that has been reflected off the walls / floor / ceiling / furniture / etc., and practically nothing that comes directly from the speaker. Everything you hear has bounced off at least one surface before reaching your ears, and most likely has gone through several such bounces. So you are totally in the reverberant field. On the other hand, if you were to put your ear right in front of the speaker, just a few inches away, then what you hear is practically all coming directly from the speaker, and almost nothing at all from the room. Everything you hear has not touched any room surfaces, and is exactly what came out of the speaker. In this case, you are totally in the direct field from the speaker. The point in the room at which the reverberant field and the direct field are exactly the same, is called the "critical distance". This isn't just a theoretical concept: it can be measured in practice. In that room, use a sound level and stand as far away as possible from the speaker while it is playing at a constant level. Move towards the speaker slowly and watch the level on the meter. Throughout most of the room the level will remain the same, since you are measuring the reverberant field, which is roughly the same throughout the room. But eventually as you get close to the speaker, the level will start rising as the meter "sees" mostly the speaker. At the point where you get a 3 dB increase, that is the "critical distance" for that room. Any closer than that and you are in the "near field": Any further away and you are in the "far field" or "reverberant field". It's that simple. As the image I posted above shows, there's a region between the near field and the critical distance, called the "free field", where things are nice and smooth. That's the best place to be. There's a lot of people who should know better than continue to buy into the "near-field / mid-field / far-field" marketing hype. Fact is, those are all just fictitious names made up by manufacturers, and gullibly swallowed by some sound engineers, studio owners, and producers, who never bother checking. Most of those would probably be shocked to learn that there is no technical definition for what constitutes a "near-field monitor", or a "far-field monitor", and even less for the mythical, non-existent "midfield". If you don't believe me, do a google search for "technical definition of near-field monitor"... :) Enjoy your search.... Here's a smattering of definitions that I've picked up over the years, not one of which is true: "Near-field monitors are short throw, narrow dispersion, limited range units." "Nearfield is a reference to the range of frequencies the speaker is capable of replicating." "Nearfield monitors are designed to be positioned approximately one to two metres away from the listener" "Near-field: a compact studio monitor designed for listening at close distances, typically between three and five feet" "Nearfield monitors are designed to sit on or just behind the meter bridge of a mixing desk, within a couple of feet of the engineer" "Nearfield monitors are small speakers which you sit fairly close to." "Nearfield is if your ear is closer to the speaker than it is to any reflective surfaces." "The whole point of small near field monitors is that you sit close enough that you don't need a treated room. Amazing how many people don't seem to get that" "Near-field studio monitors are small speakers that minimize the effects of your room on the sound source." "For nearfield monitiors, you need a listening distance that's at least 3 times the distance between the woofer and tweeter" "Near field monitoring is a way to sit closer to your monitors with the idea that sitting closer to the speakers say 3′- 4′, will reduce the sound of the room in the mix." "Nearfield simply means "close distance." "Nearfield means so close that the SPL no longer increases if you move even closer." "Nearfield means less than 2.50 meters "Near field is the critical listening distance" "Nearfield means that your ears are closer to the speakers than they are to any of the room boundaries". "Near field refers to the size of the monitor in relation to the listening distance" "Near-Field monitors are designed to be placed less than 6 feet away from the listener." "Near field listening: set them up 4 feet apart, from 4 feet away. They will sound great regardless of the room from that close". "Nearfield monitors"? = No bass, no hope of bass, let's not pretend." What a wonderful hodge-podge of garbage answers! Most are totally off, a couple get sort of close, but they are all still absolutely wrong! And mostly they contradict each other. The worst thing is, all of those come from "experts" offering thier opinions on how to set up speakers and rooms... :shock: :roll: :!: The issue is that there's no such thing as a "near field" monitor, since the term "near field" refers to the ROOM; not the speakers. If your head is closer to the monitors than the critical distance and free field for the room then you are in the near field. If you are beyond the free field or the critical distance, then you are in the far field. Period. That's it. The "critical distance" is a well defined technical term that can be predicted mathematically, and it can be measured. There's no question about where it is, or what it is. That distance varies for each room, and each set of treatment, but does NOT vary for different speakers in the same room. For a smallish to medium room that is treated one way, the entire room might be in the near field, regardless of what speaker you use, but if you take out that treatment then the near field might only extend a couple of feet beyond the speakers. In a small, badly treated room that is poorly laid out, there might be no free field at all. And in a large room, the free field might extend several meters, starting quote close to the speakers. There is nothing at all that you can do to a speaker to ensure that it will always be a near-field monitors, since that depends entirely on the room, and on where you place the speakers and your head in that room. And as both Floyd Toole and Architectural Acoustics point out, the near field is a terrible place to listen! Sorry about the rant again! But my point is that you can use pretty much whatever speakers you want to use in your room (within reason!), regardless of what it says on the box they came in. You do not have to listen close to near-fields, and you do not have to be 20 feet away to listen to far-fields or "mid-fields". And you can soffit-mount pretty much any speaker you want to, with only a very few exceptions. So chose the best, acoustically flattest speakers you can get, with the spectrum range that you need for your music, put them in properly designed soffits at the correct locations in the room, and then design the room around them, and treat the room according. If you like your A7X's, then keep your A7X's! :)
or can i perfectly soffit mont the A7X's
Simple answer:
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:)
What is rule of thumb for speaker placement angle and listening position within a room???
Supposedly, 30° angle centered on 38% of room depth... but see above... that's not true at all....
Thanks to anyone who can help me out.
You have your speakers centered in your soffits (same distance from the speaker to each edge of the front baffle): that's not necessary, and not even a good idea! You should aim to have different distances on each side, to prevent "lobing" and "focusing". I try to aim for having the speaker centered at 5/8 the width, but that isn't usually possible for construction reasons, or for room geometry. You could also consider making your soffits deeper, so the sit out further into the room. Which indirectly makes the room appear a bit shorter, acoustically, so you could slide your mix position back a bit too... - Stuart -
Hey Guys, No replies yet, but i ain't giving up! i did some research on speaker placement (RFZ) with soffit mounting speakers. the things i found and helped( I think helped and awnsered my previous questions) me ge to this point in speaker placement you can find here. viewtopic.php?f=2&t=20180&hilit=Speaker+placement&start=60 it's stuart helping someone out with some great advice!! verry interesting thread!! I changed my splayed walls( green part) to redirect some of my early reflections. I went back to 73° angle on speakers. Works est for my room I think. I used this little cool online tool to do some ray tracing in my current room. http://amray.andymel.eu/ 41504043705847<settngs>BEAMTRC<spview>53.30297565683293:59.50343824640032:1.0000000000000022<sktchpd>3%$200:596,536:596,229:165,308:106,507:165,428:106,200:234,536:234,368:106,476.12327680000004:135.88460800000001#0:1,2:3,4:5,0:6,6:2,7:4,7:1,5:3,3:8,5:9%)475.5169728407929:141.48736071148082%(368:273% if you copy paste the numbers above into the online tool you can see my room with the rays. I don't know how high the absorption level needs to be in the tool. Bt it gives a good view of where sound is going. and my first reflection is hitting me back @ about 17ms untreated. any good?? attached is the room and speaker placement with measurements. any feedback on my idea for my room is welcome. I think i have reached a good starting point for my room, but who am I, just een beginner and any pro insight would be helpfull because i am probably missing a lot. Thanks!!
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Hey stuart, didn't see your replie, I think I was just writing the above @ the same time. Going to read it now. Greets
Damn this has been an eye opening read to me. Thanks guys.
i just want to check and see if i have the right idea here. i'll make a small box that fits my monitors(adam a3x most likely) nice and tight with an air tight front panel that is cut out so that the monitor can sit flush with the face of it. then this assembly of box and monitor will sit on a riser to hold it up and the connection point will be decoupled from the box and monitor assembly. should i make the face of the box a large hard surface(maybe steel or counter top concrete), i know it's to keep all the sound directional and from bouncing off the rear wall or behind the monitor. i think my rear wall will almost all be absorptive. how big should the face of it be?
i just want to check and see if i have the right idea here. i'll make a small box that fits my monitors(adam a3x most likely) nice and tight
That's one way of doing it, yes. The other way is to make the enclosure box larger than the actual speaker, and use rubber pads to support the speaker inside. Of course, you MUST do the math in this case, to make sure that there won't be any resonant frequencies where the speaker could transmit sound into the box.
with an air tight front panel
Some people do air-tight baffles and enclosure boxes, yes, but personally I prefer to leave a small gap around the edge of the speaker., to allow for movement.... especially if you use the "rubber pads" approach.
that is cut out so that the monitor can sit flush with the face of it.
Correct.
should i make the face of the box a large hard surface
Yes, the front baffle must be solid, massive, and rigid. Some people even use stone, and the image above of the A7X mounted in a white colored soffit, that baffle actually is concrete that was poured into a carefully shaped mold, such that it accurately follows the angled contours of the speaker cabinet. That was done by one of my customers in Canada. It works very well...
(maybe steel or counter top concrete)
Possible, yes. See above. But most people make them from several layers of thick dense "stuff", such as MDF, plywood, OSB, drywall, etc.
then this assembly of box and monitor will sit on a riser to hold it up
More than just a riser! You also need a massive, solid, rigid framework to support the front baffle, and the side panels, and the top panel, and the treatment above and below the speaker... Some people build separate support structures for the speaker and for the baffle, but I don't. I prefer to decouple the speaker itself with those "rubber pads" I mentioned. Those are the two approaches you can use. Wither way, the concept is to keep the speaker and the baffle apart (decoupled) to prevent the speaker from transferring vibrations directly into the baffle. I find it more intelligent to do that at the source, and decouple the speaker from its surroundings right at the speaker cabinet, since trying to decouple an entire support structure seems to be a lot more complex, and a lot more prone to error. And a lot harder to fix if it doesn't work properly.
and the connection point will be decoupled from the box and monitor assembly.
One way or another, yes. You need to prevent the speaker from transferring energy into the soffit framing, the baffle, the support structure, and ultimately the entire building.
i know it's to keep all the sound directional and from bouncing off the rear wall or behind the monitor.
Among other things, yes! That's just one aspect. It also corrects the power imbalance, prevents edge diffraction, extends the low end response slightly, eliminate SBIR from the front wall, reduces comb-filtering, and also looks cool! :)
i think my rear wall will almost all be absorptive. how big should the face of it be?
The face of your rear wall absorption, or the face of the soffit baffle? - Stuart -
Soundman2020 wrote:
face of your rear wall absorption, or the face of the soffit baffle?
Oh I mean the hard surface of the soffit(baffle i think) that the monitor will be aimedout of. I was not sure if it needed to be a percentage of the wall or multiple of the monitor size or anything. The rest of that wall (I guess it's actually the front wall, I was thinking from the monitors point of view) I was going to make absorbent cause my room is small and they would almost be apart of a super chunk corner. I assume bigger is better but will add to reflections that bounce back n forth a few times.
Oh I mean the hard surface of the soffit(baffle i think) that the monitor will be aimedout of. I was not sure if it needed to be a percentage of the wall or multiple of the monitor size or anything.
There's a general rule of thumb that the baffle should be AT LEAST three times wider than the speaker width (assuming vertical mount). In strict reality, it is three times the diameter of the LF driver, but I prefer to use 3 x width of cabinet. So for example if you have a 7" driver and the cabinet is 8" wide, then strictly it should be MORE than 21" wide, but I would recommend MORE than 24" wide. If you can get wider than that, then even better. Also, do not place your speaker in the center of the baffle: Offset it to one side or the other. I aim for having the speaker at 5/8 of the baffle width, but that often isn't possible. For example, if that would leave you with LESS than one LF driver width between the speaker and the edge of the baffle, then don't do that. So for example, let's say that you have that hypothetical speaker with 7" driver in an 8" box, and you have enough room to make your baffle 28" wide. 5/8 of that would mean you should have your speaker centered 17.5" from one edge and 10.5" from the other edge. Since the speaker is 8" wide, obviously it goes 4" each side of it's own center-line, so the CENTERLINE of the speaker would be 10.5" from that close edge, meaning that there would only be (10.5 - 4) = 6.5" between the edge of the speaker cabinet and the edge of the baffle. No good, since the driver is 7". So move it back an inch towards the middle. Now it is centered on a point 16.5" from one edge and 11.5" from the other edge. (11.5 - 4) = 7.5". Now you are good. Borderline, but good. I would probably go another 1/2" in that case, and put it 16" from one edge, 12" from the other, so there's 8" between the speaker edge and baffle edge. In simple terms, try to have at least one "LF driver diameter" of baffle width out to each side of the actual speaker, and more if you can. The more you have, the better it is: more low frequency extension, smoother and tighter bass, more solid and clear stereo image, less artifacts, etc. Sometimes I see huge speakers soffit mounted where there's a baffle just an inch or two wide on one (or both!) sides of the speaker, and I have to just shake my head.... The entire point of soffit mounting is to emulate an INFINITE baffle as closely as possible: adding an inch to a huge speaker is pretty far from "infinite"!
The rest of that wall (I guess it's actually the front wall, I was thinking from the monitors point of view) I was going to make absorbent cause my room is small and they would almost be apart of a super chunk corner.
Then you would not have an effective soffit mount! The ideal soffit mount extends the front baffle all the way to the side wall!! If you have an edge and a gap there, then you have not removed the "edge diffraction" problem, which is one of the main reasons why you should have a soffit in the first place! You have also not added enough area to the baffle. Your bass trapping can go above and below the soffit mount itself and even inside part of it. You could do superchunks in those areas, but I normally do hangers, which are very effective, and you have a LOT of space there, actually, in a well designed soffit. Look around the forum, and do a search for the RFZ concept of room design. You'll see MANY rooms that are designed like that, with soffits that extend all the way out to the walls, often with an extra section that is angled more than the soffit itself, sort of a "wing" on the side of the soffit, that joins the soffit to the wall. Very important!
I assume bigger is better but will add to reflections
Exactly! Yes, and yes! That's exactly what you want: you WANT the soffit to be as big as possible, so that it really DOES create the reflections that you need, and send those in the correct direction....
will add to reflections that bounce back n forth a few times.
Not if you design the room correctly! The entire point of soffit-mounting in an RFZ room is that the front end directs all of the reflections away from the mix position, toward the back half of the side walls, and the rear wall, where they are properly absorbed and/or diffused, to create the low-level reverberant field ("ambiance") that then envelops the room to keep it sounding good, smooth, not tiring, pleasant, and above all, neutral. The entire concept of RFZ is that ALL early reflections are attenuated by at least 20 dB, and arrive at least 20ms after the direct sound, and are diffuse. Soffits and soffit "wings" go a long way to accomplishing that. There's much more to RFZ than that, of course, but that's the basis. Here's an example of a properly designed and built RFZ-style room : viewtopic.php?f=2&t=20471 - Stuart -
Soundman2020 wrote:
Not if you design the room correctly! The entire point of soffit-mounting in an RFZ room is that the front end directs all of the reflections away from the mix position, toward the back half of the side walls, and the rear wall, where they are properly absorbed and/or diffused, to create the low-level reverberant field ("ambiance") that then envelops the room to keep it sounding good, smooth, not tiring, pleasant, and above all, neutral. The entire concept of RFZ is that ALL early reflections are attenuated by at least 20 dB, and arrive at least 20ms after the direct sound, and are diffuse. Soffits and soffit "wings" go a long way to accomplishing that. There's much more to RFZ than that, of course, but that's the basis. Here's an example of a properly designed and built RFZ-style room : viewtopic.php?f=2&t=20471 - Stuart -
I like like the idea of rfz more that I do the non Enviroment direction I was originally going in. I notice in a lot of these designs the monitors are in the upper 1 / 3 aimed down at the listening position, I assume this bounces it off more surfaces(floor to rear to celing) so you have more chances to attenuate the energy. Would there be a down side to keeping the monitors at the lower 1 / 3 room height but angled up a bit, keeping the listener in the monitors usable angle but directing more towards the celing where I would have the most room for absorption. My rear wall is pretty close but I could build a 24~30 deep cloud in the rear celing corner that would have a better chance and taking down 20db I have been searching the web and haven't come across any pictures or designs like that. I see a lot angled down though. After looking at these rooms you have built I have completely changed my direction haha, they are amazing and seeing the results in the room response shows how much the extra work pays off. Very very motivational.
Wow guys, Getting some awesome awnsers here! A question, the front wall space between the 2 soffits should this also be like the baffle verry solid? Verry reflective? Or should i make this absorbant? The walls behind the soffit do i keep the construction the same as the rest of the walls of the room? I mean by this completly finish the outer walls and built soffit seperatly within this room? Are the angles of my current soffit wings ok? What do you think of making a verry tight closset and mounting this closset on to a plate mounted on vibration silencers , like they use in machinerie. Would this work similar to the rubber pad approach? And how do i calculate the needed rubber pads or vibration silencers neede for the speaker /closset? Thanks! Finally getting somewhere.
shimmer wrote:
Wow guys, Getting some awesome awnsers here! A question, the front wall space between the 2 soffits should this also be like the baffle verry solid? Verry reflective? Or should i make this absorbant?
I was just wondering the exact same thing!
I like like the idea of rfz more that I do the non Enviroment direction I was originally going in.
Me too! Phillip Newell says a lot of good things, but I'm not with him on some aspects of NER ("Non Environment Room") design. RFZ makes more sense, to me. CID is another interesting option, but I'm not aware of many places actually built like that, except a couple of test rooms at the BBC. So I'm sticking with RFZ style, until something better comes along...
I notice in a lot of these designs the monitors are in the upper 1 / 3 aimed down at the listening position,
In large rooms, yes, some people do that, but I prefer not to. There's a pscyho-acosutical issue that Andre brought to my attention many years ago, and there's also a reflection issue, and comb-filtering issue. First, the psycho-acoustic thing: Your ears and brain are really good at figuring out directionality in the horizontal plane. So when you are standing out in the open, looking around, and you hear a lion growl, you immediately can identify which direction that came from, and turn the exact opposite way, to run! But if you happen to be looking down at the ground with your head bent over, or up at the sky with your head bent back, at the moment when the lion growls, what do you do naturally? Very fist thing is to get your head back horizontal, and look around at the horizon, waiting for the next growl... Why? Because your ears are only good at determining direction when your head is level and looking at the horizon! If your head is titled up or down, then you CANNOT determine direction accurately! Because of the way your pinna are built (the curly twisty parts of your ear). The pinna are actually critical to determining two things: frequency and direction. They carefully re-direct incoming sound into the "hole" of your ear, and the make very subtle changes in the patterns of sound that your ear can then pick up, and your brain can process, so you can figure out which direction the growl came from, and how close the lion is. If you were looking up or down, then the FIRST thing your brain does is to get your head level and wait for another clue, because it could not determine the direction and frequency very well, with your pinna tilted up or down to the wrong angle! So your brain wants your head level, such that when the next growl comes, it can determine direction and distance accurately, and tell you which way to run. It doesn't want to run yet, because it doesn't know where the lion is. It would have known if your head would have been level, but it wasn't, so it has to wait for better info. It does not want to send you running TOWARDS the lion! :) So what does that have t do with studios? There's no lions in your studio (I hope!) But there are sound sources, and there are ears. If the sound sources come from above or below the horizon, then your brain has the same "lion problem": it can't determine direction and frequency accurately. And since you sort of do need to know what direction each instrument is panned to in your mix, accurately, it's not a good idea to mount your speakers at a place where your brain has trouble determining direction! Yeah, you could just tilt your head up a bit to look at the speakers, every time you need to do critical listening for panning, or to get a good stereo image, but why do that? You'll end up with a sore neck! Tilt head up to speakers, listen, tilt head down to console, adjust, tilt head up to speakers, listen, tilt head down to console, adjust, tilt head up to speakers, listen, tilt head down to console, adjust, ... yo-yo, ping pong, bounce-bounce, up down... sore neck! Studio design is partly about ergonomics, not just acoustics, structures, HVAC, electrical, etc. And if you have to bounce your head up and down all day like a bobble-head toy on a spring, then that's not such a good thing. OK, so what's the limit? Well, Andre led me on a long path to find out, may years ago, and I did a lot of research on that, eventually coming to agree with him that 7° is the limit. Your speakers should never be more than 7° above the horizon, meaning that they should never be angled down more than 7°. That's about the limit your ears can take and still get useful, accurate direction and frequency info from your pinna, with your head looking forward and not doing an imitation of a pogo-stick. Some places say 10° is the limit, others as much as 15°, but psycho-acoustics research suggests that 7° is as far as you want to push it. More than that, and you need to bounce your head on a spring. In a large room, you can achieve that with speakers above the window tilted down, because the mix position is far enough back. But in a small room, it's not possible. However, some people do it anyway: I suppose its out of ignorance, or indifference.... OK that's the first reason. Next, reflection: The higher you raise your speaker, the more reflections you are sending to your ears, from the surface of the desk/console/DAW! Think of this: If the speaker is directly in front of you at eye height, and the desk is also at eye height in front of you, then you are looking at the desk edge-on, so there are no reflections getting to your ears! You see the edge of the desk in front of you, and beyond that the speakers, in a direct line. So the desk cannot possibly be reflecting anything. Now imagine that you lowered the desk 2 feet (60cm). It's now below your line of sight, and there will be some sound waves from the speaker hitting the top of the desk and getting reflected up again... but they will mostly be hitting your chest, not your head. Your head is out of the direct reflection path, mostly. Now imagine that you raise up the speaker by another two feet, so it is higher than your head, and you tilt it down... now the sound waves are bouncing off the desk, directly into your face. So you have the direct sound hitting your ears, AND ALSO the reflected sound, delayed just a couple of milliseconds, or less. So you have interference, phase cancellation, comb filtering, and its at almost the same level as the direct sound, since it was a hard, clean bounce off the desk (no absorption or diffusion). That totally messes up your perception of the sound! Your brain can't handle that: it needs a delay of at least 20ms between the direct sound and a reflection in order to figure out that it was an "echo". If you don't give your brain that 20ms delay, then it cannot process that the reflection is a reflection: Instead, it thinks that it is hearing a different sound from what really came in, and it had a different frequency response from what it really had, and it came from a different direction than where it really came from! So your brain loses the ability to determine phase, frequency, and directionality. So add those issues to the first issue (that your brain is already having a hard time figuring out directions due to the pinna problem...), and you can start to see why raised, tilted speakers are not such a great idea in small rooms. That's the second issue. The third issue is another form of frequency, phase, and comb filter artifacts, and it comes from the console surface. Your console surface is full of knobs, buttons, connectors, angles, meter bridges, dog boxes, cables (and probably half-empty beer cans and 3-day old stale pizza slices too), as well as other nasty things that mess up the way sound waves move over it. That causes several artifacts, starting with a general dip somewhere in the mid-range of the spectrum, and a whole bunch of ups and downs in the same region. If you look at the un-smoothed frequency response graphs for Studio 3, you'll see a tiny bit of that. It's not very pronounced, but it's there. If we move the measurement mic just in front of the desk, all of that goes away, and the curve is ruler-flat. It's one of the consequences you pay for having a large console in front of you. Plus, in Studio 3 the speakers actually are raised up slightly, and tilted down a bit (about 4.3°, to be exact), precisely because we needed to get the speakers above the large dog-box on the back of that console. So there are consequences to doing that, but I tried to minimize them as much as possible, by choosing that angle and the distances very carefully. Rod almost choked when I told he needed to build his soffits to angle his speakers down at 4.3°.... but he did it, accurately. Right now I'm finishing up the design for a mastering studio where there will be no console at all: there's a desk, but it is small, the top face is very low down, and all of the surfaces are carefully angled to minimize reflections to your head. Mastering studios are even more critical than mixing studios, so this is very important. The customer does not want a large desk with a huge console in front of him, for the same reason: he wants clean, pure, line-of-sight to the speakers, so he hears only direct sound, no reflections or distortions from the desk. His gear will be embedded in the desk, mostly on two slightly angled "wing panels", and the angle is carefully set to minimize this "mid-range roughness" issue. Excuse the long rant, but it's important to understand this stuff if you want maximum acoustic quality in your room! So that's the long, involved, convoluted, explanation as to why I don't put speakers high up, tilted down greatly. In fact, the "standard" correct height for speakers, according to international specs for critical listening rooms, is 120cm above the floor: that's 47.25". The reason? Because that's the height of your ears, while seated! For most people seated comfortably in typical office chairs, the average ear height is 120cm above the floor. So that's where you want your speaker, too! One thing to be aware of: that's the height of the ACOUSTIC AXIS of the speaker, not the height of the top or bottom of the cabinet, nor of the woofer or tweeter. Most manufacturers publish diagrams of dimensions that show you where the acoustic axis of your speaker is located. For a typical two-way speaker, it will be on the imaginary line that joins the center of the woofer to the center of the tweeter, and much closer to the tweeter than the woofer. That's the point where sound seems to emanate from the speaker. If you close your eyes and listen vary carefully to just one speaker, and you were asked to point to the middle of where the sound is coming from, you would point to the location of the acoustic axis. That's the spot that you want 120cm above the floor. However, I normally raise the speakers just a bit higher than that, for several reasons. It depends on the speaker, the desk, the room, the treatment, etc., but it might be around 122 to 130cm, give or take a bit. That will still keep your ears on-axis with most speakers, but you do have to be careful. There's one "secret" I should mention here, though: Often those huge monster speakers you see up high and tilted down, are NOT meant for the engineer at the mix position! They are meant more for the client, sitting way back on the couch, at the rear of the room. They are often aimed at him, and he really is on-axis to them, with less that 7° tilt. Or even if it is more than 7°, it doesn't matter as he can sit there with his head slightly raised as he listens, because he doesn't have to look down at the console all the time to adjust things! He only needs to listen, so he can set there without bouncing his head at all, and he'll get food, clean, sound like that. Often, in that type of studio, the main speakers that the engineer uses are on stands behind the desk, or sometimes (gasp!) on the meter bridge! :shock: which is a terrible place to put them... He might use the raised/tilted mains to get the feel for the full power of the mix every now and then, or to listen for specifics, but mostly he'll mix on another set of speakers. Not always, of course, but quite common.
Would there be a down side to keeping the monitors at the lower 1 / 3 room height but angled up a bit,
Same problem as #1, to a certain extent: pinna, directionality, frequency response, plus the additional issue that the edge of the desk, or the console, or DAW, will probably put your head in an acoustic "shadow": if your ear cannot directly "see" the speaker, with no objects in between, then that's a problem.
My rear wall is pretty close
How close? What are your room dimensions? Where is our head located in that room, with respect to the front and back walls? Where are the speakers located? Draw a diagram for us, and take photos, so we can see your room, to understand the issues.
I have been searching the web and haven't come across any pictures or designs like that.
Right! That's for a good reason! :) Whenever you think up a "new" idea like that, and search all over but don't find any examples, then that's probably because it doesn't work! :) If it did work, someone would have done it, others would have copied it, and someone would have done some research on it. If there are no examples, that usually means someone DID try it, and it was a failure. It's unlikely that you are the first person to ever think of that, although it could happen.
After looking at these rooms you have built I have completely changed my direction, ... they are amazing
Thanks! To me, that sounds like a compliment, so thank you! :oops: And I'm glad that you have learned something from that, and can apply it to your own room.
and seeing the results in the room response shows how much the extra work pays off. Very very motivational.
As the saying goes, "the proof of the pudding is in the eating". Or maybe "put your money where your mouth is"! I can spout off about this stuff all day, but unless there's clear data to back it up, my words are pretty meaningless. If it tests well, and meets the design specs, and customer is happy, then clearly it works! I think the Studio 3 thread has a link to their own website, where there's a lot more info, including a long story about the design and build process. Rod was so happy with his studio that he asked me to write that up for him, and he put it in the website. So go looking for that link, and have fun reading about some of the "behind the scenes" info on how we designed and built that place. Some might find it boring, but you might be able to glean more info from there to use in your place.
A question, the front wall space between the 2 soffits should this also be like the baffle verry solid? Verry reflective? Or should i make this absorbant?
You can do it either way, but I usually prefer to keep it soft and absorptive. Sometimes that isn't possible, such as in this room I designed for a customer in Australia:
Image not preserved: BRAUS--Rear-left-to-front-IMG_0261-ENH.JPG
As you can see, there are sliding glass doors in the space between the soffits, leading into the isolation booth, so it's impossible to cover those with insulation! So I had to use other "tricks" to make that acceptable... :)
The walls behind the soffit do i keep the construction the same as the rest of the walls of the room? I mean by this completly finish the outer walls and built soffit seperatly within this room?
Yes, basically. But I normally do control rooms "inside out", all around, so the front wall actually has the studs facing you (with insulation between them, and the drywall on the other side of the studs, which makes it easier to tie the soffits into the front wall properly.
What do you think of making a verry tight closset and mounting this closset on to a plate mounted on vibration silencers , like they use in machinerie. Would this work similar to the rubber pad approach?
You could, yes, but you'd still need to tune that to ensure that that resonant frequency is at least an octave below the lowest frequency that the speaker will produce. So you need to calculate that carefully.
And how do i calculate the needed rubber pads or vibration silencers neede for the speaker /closset?
That's a little more complex! The equations are rather involved, and you need to know things like the spring stiffness for the material you will be using, or the Shore hardness, or the resilience, and the weight (mass) of everything that you need to float... The basic equation is: f= 1/(2 PI) x SQRT (K/N) Where: f = the resonant frequency K = the stiffness of the spring you are using, and M = the mass of what you are floating However, there's more to it than that. You also need to take into account the damping, transmissibility, and other things. There are other ways of calculating this, but it depends on the TYPE of spring you are using. There are differences between steel coiled springs, and rubber pad "springs", that you need to consider: coil springs are linear, for example, but rubber is not. However, rubber has some self-damping properties that steel springs do not. Etc. Damping decreases the amplitude of the vibration ant resonance, so it's a good thing, but it also flattens the Q of the resonance, which is both good and bad, from different points of view. Bad in the sens that it increases transmissibility around the resonant frequency more than dampened springs do, so you need to have a lower resonant frequency. There's another form of that spring equation that might be helpful: f= 1/(2 PI) x SQRT (g/Delta) Where: f = the resonant frequency Delta = the static deflection of the spring when loaded down with your speaker (in meters) g = the gravitational constant (in m/s^^2) The best thing you can do is to decide on the type of spring that you will use, research all the properties of that type of spring, then use the equations for that type of spring to figure out how thick to make the spring, and how much it needs to be deflected (compressed) in order to provide the correct resonant frequency. I'm a big fan of Sorbothane rubber: I think it's the best stuff out there for floating speakers. Other people prefer EPDM, or Neoprene, or even products like Sylomer, or even natural rubber. All have their advantages and disadvantages, but for the way I do it, Sorbothane gives me the best balance of all factors. And they have software that helps you figure it out! :) In very general terms, for most materials you are looking for a static deflection of about 10% to 20% of the unloaded spring, but the optimal deflection depends on the actual material. I wish I could explain it more simply, but springs are strange things.... - Stuart -
Holy..... Stuart this is getting crazy dude. alright, I have been looking @ these equations for weeks now and I just can't wrap my head around it. I tried the sorbothane calculator and if I understand this right it tell's me to use one sorbothane insulator of 4X4X7(thick) inch for one adam speaker. or should I use 4 little ones and fill up the cavitie in the box with insuation? this can' t be right??????? please see calclation pic below. The things i know are: lowest frequentie from adam a7X = 42Hz -> octave lower = 21HZ minimum. Mass = 9,2kg or 20,3lbs per speaker. the stiffness of sorbothane I can't seem to find anywhere = K ?? so if I understand a verry little bit the resonant freqentie of my design should be 21Hz or lower?? please enlighten me I'm feel like getting nowhere and just want to make music. Another problem , I live in belgium and can't seem to find sorbothane around here, so I already contacted sorbothane if they ship here. I hope so.... Thanks!
Image not preserved: sorbothane calculator.jpg
Hey Stuart, I was thinking, maybe totally wrong thinking of me bt bare with me my head is spinning right now. If I make a tight fitted box for the adam a7X make it(the box) heavier and let it rest on one big sorbothane pad. if i follow the calclator. I guess this could be an idea.????
Image not preserved: sorbothane calculator2.jpg
Sorbothane just replied. only on amazon via isolate it. Lol! just found this smilies and i feel like the donkey/horse! lol! :horse:
I tried the sorbothane calculator and if I understand this right it tell's me to use one sorbothane insulator of 4X4X7(thick) inch for one adam speaker. this can' t be right??????? please see calclation pic below.
Correct! It can't be right...
The things i know are: lowest frequentie from adam a7X = 42Hz -> octave lower = 21HZ minimum. Mass = 9,2kg or 20,3lbs per speaker.
So if the speaker weighs 21 lbs, and you plan to have it resting on FOUR PADS (!) then each pad will only have 1/4 the total weight resting on it. So it would be something like this:
Image not preserved: shimmer-sorb-calc.jpg
Resonant frequency is below 21 Hz, isolation at 42 Hz is 42%. Pretty reasonable.
Sorbothane just replied. : only on amazon
Or ebay : https://www.ebay.com/sch/i.html?_from=R ... e&_sacat=0 Several sellers there... - Stuart -
Ok I get the idea, didn't think I needed only 4 sotbothane pads of 1 inch to achieve the needed insulation. But I got A mind screwer here. I filled in the same data into the new sorbothane calculator and got diffrent result then you Stuart. strange... but back to the basic principle. So I make an enclosed box where the speaker is mounted inside resting on the 4 pads. I make the box larger then the speaker so i can eventually a fit larger speaker into it if needed in future. But what about the sides and top of the speakers? Put pads there also? but this raises the question? Those pads are not loaded with weight so how calculate theire size?or just fill the cavity between box and speaker with rockwool?? or use pads bottom side and top and fill up the rest with rockwool? Then mount this box on too a verry sturdy stand. Should I isolate the box from the stand? also with sorbothane? This stand should I mount it onto the basement floor? or the studio floor? the cavity between box and speaker I fill up with rockwool?? I'll make a rough idea drawing soon. And Stuart i just want to say I am unbelievablie gratefull you are whilling to help me out here! Thank you!
Image not preserved: sorbothane calculator3.jpg