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RDR
30-09-2006, 07:02 PM
Found this in my pro-tools user magazine.

It relates to pro-tools, but the technique could easily be transfered and is a continuation of the 'Room rinsing' discussoion in another thread.

Pump the Music, Pump the Sound
Now that you’ve got your reference listening level sorted out, let’s test your studio for any troublesome frequency ranges. Ideally, your studio and monitoring environment should have a relatively flat frequency output, at least in your primary listening area (along the median plane between your speakers, as described in the last Groundwork column). One way to check this is to send pink noise on each octave band through your speakers and listen for any boost or cuts in level.

With your sound level meter still in hand, let’s start the test. Unmute the “Pink Stereo” track in the Pro Tools sound level test session. When you press play, this track will generate pink noise at 1/3 octave bands in each octave at eight-second intervals, centered around the following frequencies: 31 Hz, 63 Hz, 125 Hz, 250 Hz, 500 Hz, 1 kHz, 2 kHz, 4 kHz, 8 kHz, and 16 kHz. Listen and check your sound level meter for any differences in level from one frequency band to the next. If you see or hear any differences in level between frequency bands, you may have identified a problem in the frequency spectrum that is affecting what you hear at your monitoring position. (Please note that this is a quick and dirty approach to testing your room with Pro Tools. It’s not a substitute for the more accurate tests that qualified acousticians can perform.)

What should you do if you spot a boost or cut during this test? There are a few options. First, you can choose to add an equalizer to your monitoring output signal path. This could be a hardware EQ inserted after your main output from Pro Tools or an EQ plug-in on your main output Master Fader track in your Pro Tools sessions. Either way, use the EQ to adjust the output signal with the pink noise test so that you have a flat frequency output in your listening position. Second, you can use acoustic treatment to fix a frequency problem. For instance, you can purchase bass traps if you have a bass boost in your room. Alternately, you can forget the EQ and acoustic treatments and simply try to mix with your room in mind. If you know there’s a cut in the high-mid frequencies because of some acoustic treatment on your walls, you can deliberately compensate for these frequencies when you mix or master so your songs don’t overemphasize the problem frequencies in the final mix/master. It all depends on how well you know your room.

Another way to offset frequency problems is to adjust your speaker’s EQ settings, if present. For instance, Mackie HR824s have several EQ settings that affect what you hear from them, including a high frequency 2 dB boost/cut, three different bass cutoffs, and an acoustic space (room compensation) switch. Consult the manual for your speakers to see if there are any options that might help improve your listening environment.

nova
03-10-2006, 01:54 AM
you know loads dodgy :toast: good stuff man

RDR
03-10-2006, 12:54 PM
All copied chief.. all copied...

I learn from it too though so thats cool. ;)

danielmarshall
03-10-2006, 03:08 PM
And a man of modesty too :)

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