Pro Audio with StudioMike

Reverberation is an essential key in recording and mixing. Reverberation allows the user to give the listener a change in perception of space and depth. In this post I will be describing the proper way to use reverberation and also tips on how to prevent excess reverb from entering your recording.

Im going start off with preventing excess reverb from getting into your recordings. This is actually a good continuation of my first post because excess unwanted reverb would actually be considered noise and would actually degrade the quality of your recording. The reason why I say unwanted is because some studios, mostly only the high end studios, have live rooms built to have sympathetic reverberation that can be used in the recording. The budget it takes to produce that sort of room is tremendous making it unpractical for smaller studios, like myself, to take that route. So the best bet for a smaller studio is to get as dead of a recording as possible meaning little to no reverb or reflections. This way you have total control in the mixing stage of how you want your signal to be perceived as far as space and depth is concerned.

So how do we make a recording dead? One way is by going to your local muzik store and purchasing some acoustic foam. This foam comes in pads and is engineered to prevent reflections. If you have a smaller budget and are looking to use stuff that you already own there are still ways to achieve a dead recording. The first item that you can use is a blanket. The density of the blanket will determine how much reverberation will be absorbed. The next item that can be used is your mattress. Using a mattress is actually a great way to isolate a section of a room for a better recording. now the next important step is how you have it set up.

For those of you that have a closet that you can dedicate to recording in your best but is to get some thick blankets to cover the walls. If your closet is a little bit bigger it would be ok to leave some of your clothes that are hanging up because they will help absorb reflections. It may not be a million dollar studio but it will get the job done. 

For those of you that do not have a closet to use your not completely out of luck. Here is when you pull out your mattress. What you want to do is use the mattress to create an area of isolation. You can start by picking a corner of the room that you want to do the recording in. As shown in the illustration you want to use the mattress to create the third wall making a little cubicle. For the 2 remaining walls you can use blankets to also help assist in preventing unwanted reverberation into your recording. For this set-up I would recommend using a cardiod microphone with the source of the signal facing out the corner and the mic facing the corner as displayed in the illustration. This will help prevent additional reflections from entering your recording.

What is a good signal when recording? I figured that i would start my first post with this topic because a good signal when recording is the first step in a good final product. Im not going to go into detail about what mic you should get or what signal chain you should use. These are very general concepts that when applied properly can make a world of a difference.

The first concept that should be understood is the signal to noise ratio. The signal being the source that you are attempting to record and the noise being everything else. The greater the difference between the two the better the recording. For example, if you are not fortunate enough to have a vocal booth and you are recording in an open room there are still ways to optimize your recording. First think about all the potential noise that could be bleeding into your recording. (Noise being transmitted from adjacent rooms, noise being transmitted from outside, etc.) Your objective is to get all the noise to a minimum. Closing windows helps prevent outdoor noise. Turn off all devices that are noisy like ceiling fans, regular fans, A/C units etc. You may even need to go next door to your brother or sisters room and ask them to please be quiet for a little while. (good luck with that)

Ok so now that we got the noise under control its time to focus on the signal. Now the objective is to have the signal as loud as it can be without clipping.

On audio track one you can see that the source was recorded to loud. If you look to the left of the audio region there is a red dot at the top of the meter indicating that the signal was to loud and there is a possibility of distortion. On track 3 there is a very low level that was recorded. Depending on how low your noise floor is, you may be able to get away with it. But with the recording on track 3 you may run into problems when your ready to compress the signal because that actually raises the noise floor. The audio recorded on track 2 would be your optimal choice.

Now there are 2 variables that effect the outcome of the recorded level into your host program. The first is your input gain which is the level knob used to increase or decrease the source signal going into the host program. The second is the actual output level of the source itself. This concept is very important and applies to more than just studio recording.

The first step that you want to do is make sure the source is providing a strong enough output. This can be achieved simply by projecting your voice. The lower the sources output means that there will be more noise in the recording. The stronger the sources signal the less noise that will come through the recording because the source signal will be strong enough to mask or over power the noise from being audible in the recorded signal. 

Now that you are getting a strong signal from your source its time to manipulate your trim POT or input gain knob. While making sure that the source remains consistent with its signal, begin to raise the gain knob until your signal is entering your host program at your desired level. The desired level being a few notches right below clipping. 

One thing to be careful of is vertical zoom. it will make your waveforms appear larger than they really are. The easy way to check is to look at your meters. If your waveform is large and your signal in the meters are low (Providing your fader for that channel is at unity gain) you may have to adjust your vertical zoom down to make the waveforms smaller. 

                   (This control panel is located in the top left hand side of your protools DAW)

Another way to tell is if your waveforms are small but squared off at the top and bottom. this means that your signal is distorting even though the waveforms looks small. By default vertical zoom is left at normal but if u were to ever run into this problem now you know the solution.

         And that concludes this post on getting a good signal when recording. Next weeks topic is going to be Reverberation. Ways to prevent it from getting into your recording and how to use reverb plugins to manipulate your recorded signal.  Please feel free to question and comment on anything that i said in this post. Hope you found this post useful.