Hi everybody
I have a problem with a controll room i build last weekend in Hanau germany.
first of all here is the layout.
http://xs73.xs.to/pics/06122/MoStudioplan1.JPG
and here some pics in the building progress:
http://xs73.xs.to/pics/06122/IMG_0354.jpg
http://xs73.xs.to/pics/06122/IMG_0364.jpg
http://xs73.xs.to/pics/06121/IMG_0358edit.JPG
http://xs73.xs.to/pics/06121/IMG_0379edit.JPG
http://xs73.xs.to/pics/06121/IMG_0368edit.JPG
http://xs73.xs.to/pics/06121/IMG_0369edit.JPG
The romm sounds good, and the stereo image is perfect but i have a big problem with the Subbass.
Everywhere in the romm there ist nearly no bass under 50 hz only at the place where the sofa is, you can hear the deep bass.
I dont know why its like this.
Is it possible to have too much bass absorbation???
The Romm is not finished jet, but all acoustik construktions are allready inside, only the cosmetic work is before me
please help me in this situation and sorry for my bad englisch. :oops:
peace
mika
:D
Please help me to find the fault John
Originally posted at johnlsayers.com, topic 5866.
I don't know the technical side of this stuff totally yet, but I can say that I've never seen that much rockwool in a control room before. Normally if the walls are shaped like that with the angle, they're actually made of drywall, but you actually made the walls out of rockwool. Maybe it IS posible to have too much bass absorption. I've definitely never seen a room like that before...
First post, a total newbie, long time lurker
but i give it a shot
I don't see any bass trap.....50hz is not covered by rockwool itself, you need traps (hangers etc), especially on 90° corners
Maybe I'm saying bulls*it, if so forgive me! :oops:
Aloha and welcome to the forum, mika
If I may ask a couple of questions:
- What is the height of your room?
- What is the construction of room? (Outside to inside)
- What kind of monitors are you using? Woofer size?
- How high from the floor to center of woofer?
It is not uncommon for bass to build up at the rear of the room, especially with the minimal absorption shown in your diagram. So take a deep breath, relax, and let's see what kind of figures you can provide, and what necessary steps are needed.
Aloha 8)
I don't know if you guys aren't seeing what I'm seeing in his drawing, but it looks like his walls are made completely out of rockwool only with slot resonators covering that. It looks to me like in the front corners of the CR he's got a ton of rockwool in the corner.
Mika, please verify what you have on the walls. From the drawing it looks like you've made the square walls out of studs and drywall, and then actually made walls inside that completely out of rockwool and insulation, giving you multiple square meters of bass trapping. And if all you did was cover that rockwool with slot resonators one could assume that most of the sound goes through the slot resonators and into the rockwool to be absorbed. Maybe I'm misenturpreting your drawing.
:D Hi thanks to all of you for reply so fast.
Ok i try to answer your questions
@ kendale
The romm hight ist 2,47m
for roomconstruktion see the updated layout
the speakers are Alesis M1 MK2 an they are hanging 1,55m over the floor
They are not flushmounted!!, only moved inside the cornertrap wich is only Rockwoll coverd with cloth (fake wall) because they are not made for suffit.
http://xs73.xs.to/pics/06123/MoStudioplan2.JPG
now thanks again for your hepl.
Im glad to know this Forum.
maybe i try to learn english :wink:
peace
mika
The speakers with 6.5" diameter woofers? These are not providing a significant output at 50 Hz in the room? Andrethe speakers are Alesis M1 MK2
Aloha mika,
Andre is right. With a 6.5" woofer, your monitors are not producing a significant amount @ 50Hz. Not that it isn't at all, but it's just not a significant amount to fill your room at that freq. What you are probably hearing at the sofa location is a buildup of 77Hz, 116Hz and 155Hz. (see attached. Note green outlined area.)
What you could try is moving your sofa out to where the listening position is about 11’ at your ears. If this sofa position interferes with your door, you could try either a smaller sofa or two chairs, or possibly reorienting your door to open out.
Next, for the most non-invasive test, try repositioning a couple of your wall panels across the two rear corners of the room – floor to ceiling. You will most likely hear an improvement in the low end absorption at the rear of the room, similar to what you hear up front. If that works for you, you might want to finish treating the back wall with a couple of floor to ceiling corner absorbers like those found here: http://www.johnlsayers.com/HR/index1.htm
If you need more low freq’s @ 50Hz and below, try adding a sub after the above suggestions.
So what are you planning to cover the front portion of the wall with? Cloth or more wood slats? And the area around the monitor face? Here’s an excerpt from the “Speaking of speakers section:The speakers are Alesis M1 MK2 an they are hanging 1,55m over the floor. They are not flush mounted, only moved inside the corner trap which is only Rockwool covered with cloth (fake wall) because they are not made for soffit.
Also, be sure to provide adequate cooling for your monitors as this may pose an issue with overheating/shutdown/fire hazard. Final question: Is that a radiator pictured on your back wall below the curtains? Be careful of any fire hazards that it might pose. Hope this helps, Aloha 8)http://johnlsayers.com/phpBB2/viewtopic.php?t=718 Here is a method for a flush mounting that I developed a couple of years ago. It provides for a simple modification method when upgrading your monitors. It also helps isolate the speaker cabinet vibrations from the control room. The picture below depicts the basic design. The front bezel is clear in the picture to help visualize the whole setup. Here is an outline of the method: 1. Create an opening that is large enough to accommodate your monitor or any monitors you might potentially use in the future, plus some extra room for sound absorption material. Building a larger space than what you presently need gives you the flexibility to upgrade. Avoid building any structures that directly couple the inner and outer framing. 2. Rigidly mount an adjustable shelf to the inner framing. Mounting to the inner framing isolates the cabinet vibrations from the control room. I've depicted small wooden rails attached to the shelf to maintain the monitor's lateral position. A belt clamp thens hold the monitor firmly to the shelf. The face of the monitor should be flush with the front wall. 3. Screw mount a rigid bezel to the outer framing. The bezel should be flush with both the front wall and the front of the speaker. The more massive and rigid the bezel the better. The opening should not contact the monitor cabinet, but the gap should be no more than 5mm (3/16 inch). You might have the idea of filling the gap with some sort of gasket, but this is both unnecessary and detrimental. Any gasket will increase the transfer of vibrations to the bezel, therefore, effectively increasing the cabinet radiation surface area. Gaps less than a half wavelength will have little effect on wave propagation. 5mm is less than 1/3 wavelength at 20kHz, so audible diffraction induced by the gap isn't an issue. In any case most tweeters radiate very little energy 90° off axis at 20kHz. When you upgrade your monitors all you need to do is remove the bezel and cut a larger size opening, readjust the shelf, then mount the new speaker and screw the bezel back in. 4. Fill the extra space in the mounting cavity with sound absorbing material like fiberglass. This will help absorb sound radiated from the monitor cabinet. You might have noticed that a big part of this mounting method centers around isolating the monitor cabinet energy from the control room. Loudspeaker cabinets are almost invariably under-constructed and can radiate a significant amount to energy, resulting in coloration. If you follow these design principles, I think you'll hear a noticeable difference from a simple flush mount.
Hi everybody
first off al i have a update for you
i coverd the 30 degrees angeld frontwall with 19mm strong wood, and the midle ist built as a slatreso.
http://xs74.xs.to/pics/06131/IMG_0396klein.JPG
the cellig becomes a cloud
http://xs74.xs.to/pics/06131/IMG_0399klein.JPG
the basssound is now more constant in the roompsoitions, but how can i optimze it, so that everywhere in the room i have a nearly constant basslevel?
is it possible?
thanks for your help and best regards from germany
peace
mika
It's nearly impossible to make the bass response consistent everywhere i nthe room. That's why you tune your room from the mix position.
it's perfectly possible to make the bass consistent everywhere in the room - that's the whole idea. cheers johnIt's nearly impossible to make the bass response consistent everywhere i nthe room. That's why you tune your room from the mix position.
Aloha mika,
What other treatments have you done to the room, especially in the rear section? Aloha 8)the basssound is now more constant in the roompsoitions, but how can i optimze it, so that everywhere in the room i have a nearly constant basslevel?
Thanks John you make me hope
Thanks Kendale for your competent help
i did in this moment nothing in the back of the room. The only chnages are to soffit the monitors in a 19mm MDF wall, and cover the middle front with the slatreso.
In the back ist not enogh space to do something, its impossible to hang the broadbandabsorbers cross the corner. Its mostly an optical reason, but to feel home in the studio is same important like to hear good in the studio.
A way to fight the axial waves in the back is maybee to build aborbers and hang it cross the backwall and the celling.
Do you think it can give the same effekt like absorbers cross the corner?
hope to get friendly help like everytime here in the forum
peace
mika
Aloha mika,
Yes, it is important to feel at home in the studio.
Is it as important as "making the bass consistent everywhere in the room?" It's your choice. Most of the guys here are trying to help each other achieve the best results possible by the advice/questions offered. After all's been said and done, it pretty much comes down to what do YOU feel is more important for YOUR studio.
In order to absorb the low frequencies your room is producing, I doubt you'll have the same affect as corner absorbers across the corners using the kind of panel absorbers you have pictured. To optimize your room at both the mix and sofa positions, you need to position (or reposition) yourself in the optimum listening positions (avoiding peaks and nulls) and treating the room with the proper absorbers in the right places and in the right amounts. Anything else would be a compromise, which usually results in less than optimum results. Oftentimes, compromises are unavoidable. I am currently in a compromised situation. And while the advice and acoustic treatments that have been done have vastly improved my mix position, there are still areas in my room that fall short of what I would have hoped for. Had I been/when I am able to build from the ground up, I would definitely make the choices to make the changes necessary in order to optimize the whole room. Ultimately, the choice is yours. Choose wisely, my friend. :wink: Aloha 8)A way to fight the axial waves in the back is maybee to build aborbers and hang it cross the backwall and the celling. Do you think it can give the same effekt like absorbers cross the corner?
I think I'm a bit confused... why are all tests done strictly from the mixing position? Why not just put the mic anywhere in the room? I thought the whole point was to tune the room to where you sit when you're mixing. I've heard people say around here that you're not even really supposed to move your head outside the sweet spot. Up until fairly recently I've only been concerned about finishing construction on my studio and only lately have I started learning the technical aspects of bass traps and tuning a room. I'd really love to hear this explained.it's perfectly possible to make the bass consistent everywhere in the room - that's the whole idea. john
because the frequency response of the speakers is directional and they are aimed at the listening position. Step off axis to a speaker and the response changes. Low end isn't directional and fills the whole room. cheers johnI think I'm a bit confused... why are all tests done strictly from the mixing position?
Of course!!! I get it! :) Good answer. Oh man I feel like I'm really learning now!!!