hey all,
the control room i'm going to build will be somewhere the size shown in the pic. if i want to put the listening position at 38%, does it have to be measered from the window to the bass trap or from the window to the corner of the room (inside the bass trap)?
i'm a bit confused about this....
thanks,
arjan
question about the 38% rule
Originally posted at johnlsayers.com, topic 10441.
The ideal listening position is 38% away from the wall you will be facing when looking at your monitors. I guess you will have the bass trap behind you, so 38% from the window. The listening position is measured just past your head. Also, remember the equilateral triangle rule. Looks like you will have fun with acoustics in that shape room, I think (?). Don't forget absorption in the corners facing you and 1st reflection points - side walls, ceiling, floor, rear walls etc, but hey, I'm no expert :lol: Good luck.hey all, the control room i'm going to build will be somewhere the size shown in the pic. if i want to put the listening position at 38%, does it have to be measered from the window to the bass trap or from the window to the corner of the room (inside the bass trap)? i'm a bit confused about this.... thanks, arjan
If my room is only 14 long should I still use the 38% rule?
It winds up that 38% of 500cm = 190cm and 38% of 400cm = 152cm. Only a difference of 38cm. If the back wall is a hard boundary seems like the less of the two, 152cm, would be a better starting place. Thats just my opinion of the math boss.hey all, the control room i'm going to build will be somewhere the size shown in the pic. if i want to put the listening position at 38%, does it have to be measered from the window to the bass trap or from the window to the corner of the room (inside the bass trap)? i'm a bit confused about this.... thanks, arjan
keeping in mind 38% is the starting point, not necessarily the finish line...
thaks for the replies.
my concern is that 38% of 400 cm is almost 50% of 500 cm...
that will be a problem i think...
yellowfever, why do you say i will have fun with the acoustics in that room?
is it so bad of a shape?
38% of 400 cm(152cm)
50% of 500 cm(250cm)
difference of 98cm(a little over three feet!) Lot of wiggle room there ;)
Like Glenn said "38% is the starting point, not necessarily the finish line..."
I would never dream of criticising any members room shape; it just seems to me that working out your acoustic treatment will be a very hard task. All of the designs I have seen show 2 rear corners with bass trapping, rather than coming to a point. As I said previously, I'm no expert. I'm sure other people are better qualified to pass opinion than me ?! Is it an existing room you're converting or a new build?yellowfever, why do you say i will have fun with the acoustics in that room? is it so bad of a shape?
I would never dream of criticising any members room shape; it just seems to me that working out your acoustic treatment will be a very hard task. All of the designs I have seen show 2 rear corners with bass trapping, rather than coming to a point. As I said previously, I'm no expert. I'm sure other people are better qualified to pass opinion than me ?! Is it an existing room you're converting or a new build?yellowfever, why do you say i will have fun with the acoustics in that room? is it so bad of a shape?
sorry xspace, i ment the other way around...
50% of 400 cm is close to 38% of 500 cm.
yellowfever, it's a new build.
it's actually based on the shape of the room on the cover of rod gervais' book... i thought if he puts something on the cover of his book, it must be good! :?
the room will also be in the corner of a larger building.
it's the story of my life :)sorry xspace, i ment the other way around...
keep in mind you want to create a equilateral triangle for the monitors so you need to look at the width of the monitors as the approx depth for the seating. so if you can space the monitors 280cm, then your seating is going to be 280cm on each leg as well. so the 38% rule might not be applicable unless your far enough from the front wall (which then could result in low mid cancellations at the sitting position).
as far as treatment, you want the back corner to be a bass trap, and you'll need reflection treatments on each side of the back walls as well. plus there is no door shown so you may have other compromises yet to be made.
lastly, if you check Rod's CR layout, there is a front wall indentation, its not a pentagon...
what are the advantages of the front wall indentation versus the pentagon?
could this design (pic) work?
here my monitors are plusminus 150 cm apart and the distance from the front wall to my head is also 150cm more or less so thats close to the 38% from the front wall to the bass trap.
the indent gives you some more space up front for the monitors, windows, and some additional trapping. since the bass trap is going to be pretty dense acoustically, i think its safe to start with this latest layout.
I think although you have got the 38% rule about right for the location of you, the location of where you sit and the monitors should form the 3 points of an equilateral triangle. So, if I'm reading it right, the distance between you and each ot the monitors will be less than the spacing of the monitors apart ?! I think !what are the advantages of the front wall indentation versus the pentagon? here my monitors are plusminus 150 cm apart and the distance from the front wall to my head is also 150cm more or less so thats close to the 38% from the front wall to the bass trap.
I accidentally hit New Post with this earlier. It must have looked odd without any context. Corrected now. My apologies.
Hi Barefootstudio, since this is a new build I think it would be wise to hire someone with experience. I am a fledgling Acoustician, but I wouldn't dare take on a job like this. Perhaps John Sayers, or someone in your own country.
Best Regards, Dan FitzGerald AMIOA
www.soundsound.ie
just curious - is this the only room shape you can use?
gulffo, is the roomshape that weird?
dandan, i am hiring someone for the moment.
well, actualy 2 people. one for getting the studio "soundproof" and one for the inner acoustics and cabling. me and my friends will build it.
after reading rods book and studying this very website for a while i showed my floorplan to the guy who will take care of my inner acoustics and he said it was ok.
because the original floor was so uneven we started with putting 10 cube meters of "chape" (a mixture of sand and cement) on the floor to even things out. thats a very common practice here in belgium.
i thought it would be a good idea to make sure the chapes for the different rooms had no contact with each other so we divided the floor according to the floorplan in "rooms" with wood and polyutherane (see pics) and filled those "rooms" with the chape. i will pull the wood out later and fill the empty space between the chapes with foam. we also have put the pipes for multicables and electricity in the chape (see pics), so i dont have to go trough the walls with them.
so it is no longer possible (i think) to change the floorplan, because its already layed out with the chapes for the rooms and all wires come out of the ground where they should.
do you think i'll have problems with a control room of that shape?
some explaination for the floorplan:
the bathroom was already there, built in brick.
the space between the rooms is not to scale. it's more like 2 to 5 cm between the rooms. the chapes have no contact with the outer walls.
i hope i made myself a bit clear with all that "chape" thing cause i don't know how to explain in english...
and the floorplan itself...
if you want some more explaination or pics let me know!!
no comments?
:(
looks cool! we're waiting on the rest of the pics :-) you might also post this thread (or have it moved) to the construction forum... ;-)
so the shape of the control room is no problem then? :?
nope because you're going to add a bass trap in the back and some absorption on the sides as needed to cut any reflections... :?