Room mode problem, please help!

Posted: Thu Nov 20, 2008 1:16 pm

I'm having a major room mode problem. My mixes sound ok to me in my room but when played on other systems in other rooms/places they all tend to have an abundance of low freq. boominess. I have used a mode calculator to calculate all the room modes.

Now that I know what they are, what is the most practical and cost effective way to fix this? any way someone can break this down for a beginner?

I have built four acoustic panels and have egg create foam covering most of the ceiling. Two panels on the side walls half way btwn me and the speakers and two behind me on the back wall at ear level. Four foam (probably not that effective) bass traps at ceiling height in all four corners.

Thank!

Posted: Thu Nov 20, 2008 2:26 pm

Change things to improve them. How much more do you expect with the information you gave? In no order, give:

room dimensions
mode analysis results
speaker locations
listening position
current treatment types and locations.

Andre

Posted: Thu Nov 20, 2008 2:54 pm

...and what type of wall/ceiling/floor surfaces exist in the structure.

Posted: Thu Nov 20, 2008 6:35 pm

You are too green to understand that the problem is not the room.

The problem is in how you are interpreting what you are listening to through your monitor system. You obviously haven't started with any kind of well-known reference? References such as others famous recordings of various genres. Once you understand how those sound, you're mixing style should change. If it doesn't change. You are stupid. You're not listening. And you cannot rely on a single pair of speakers in any room. You haven't spent $500,000 on acoustic treatment have you? No. I didn't think so. Not planning to either are you? No. Your parents would like that either.

So what to do? Blame it on building materials is easy. Learning how to listen, requires your undivided attention. Listening through headphones, speakers, records of all sorts. Practicing your training while sitting in restaurants listening to other people's conversations on the other side of the room. Now that's ear training. Ear's don't tell you what you want to hear unless you tell them what to listen to first. I can mix a perfectly wonderful mix, on anything, with anything, anywhere, anytime because I know what I'm listening to. Start listening. Stop blaming equipment and walls. They didn't do anything to hurt you.

Delivering the best recordings under the worst conditions. Live.
Ms. Remy Ann David

Posted: Fri Nov 21, 2008 1:38 am

It also doesn't hurt to sweep the room.

Here is a poor mans method:

Do you have a flat frequency mic?

If you do, get a function generator or download one from the net. This something allows to send sine waves to your speakers and adjust the frequency and amplitude.

Put the mic in the mix position, where your ears normally are.

Put on ear protection!

Turn on the function generator, set up a 1kHz sine, set the amplitude so it reads
–15dbFS or -0dbVU or less.

What’s important is that you save some headroom for larger signals. But don’t set is so low that you can’t see smaller signals. Oh and use only one meter for your measurements, don’t add any unneeded complexity.

Now set the function generator to 20 Hz, record the dBFS or dBVU value.
Repeat for all frequencies you like to 20kHz

I would typically pay more attention to the low end.
20,30,40,50,60,80,100,120,180,200,240,300,360,420,480,500,800,1000,3000,5000,8000,10,000,12,000,15,000,18,000, 20,0000

Now take your data and graph it using excel or something like it. This graph
Should read dBFS or dbVU on the Y axis and frequency on the X axis.

You can use a log scale on the x axis if you like.

This will give a very crude bode plot of your room, speakers, amplifier, sound card out, mic, pre-amp. In the other word your whole system and how it reacts together, it won’t tell you what part of the chain is causing the response.

Now so you know what your room looks like, try moving the those bass traps around and see if you can flatten the response out. Remember even in the best room a + or - 6dB frequency is hard to achieve. So don’t expect a ruler flat response.

Anyway I hope this helps.

Posted: Fri Nov 21, 2008 4:51 am

Link, thanks for all the info I will def. give that a try and see how much I can improve things.

Remy, I went back and used a reference. Improved upon the mix a great deal. I don't live with my parents just new to recording and critical listening...

Posted: Mon Dec 01, 2008 1:10 pm

link0126 wrote:

I'm having a major room mode problem. My mixes sound ok to me in my room but when played on other systems in other rooms/places they all tend to have an abundance of low freq. boominess. I have used a mode calculator to calculate all the room modes.

Now that I know what they are, what is the most practical and cost effective way to fix this? any way someone can break this down for a beginner?

I have built four acoustic panels and have egg create foam covering most of the ceiling. Two panels on the side walls half way btwn me and the speakers and two behind me on the back wall at ear level. Four foam (probably not that effective) bass traps at ceiling height in all four corners.

Sheesh! People can be brutal to beginners on these forums. I'm not an expert, but I used to experience the same trouble. So I read and read and read. And read some more about mixing. You need to develop your ear in your studio system. Burn your mixes to a CD and listen to them on every audio system you can find, in your car, in your friends' cars, headphones, home stereos. Everywhere. If you find that your mixes are too heavy on the bass, go back and roll off the low end and listen in your mixing environment to how it sounds. Then take your CD back to all the other audio systems and listen again. Do this until your mixes start sounding right. You'll develop an ear for how mixes should sound in your studio environment and you'll have less trouble translating them into other systems. It worked for me. But it took a lot of time and experimenting, even using quality gear.

This topic sponsored by: