The Basics of Digital Audio

Before we can understand digital audio, we must first have a very general understanding of how sound occurs naturally. Sound is actually a mechanical wave that is propagating through the air (typically, but it can travel through other mediums as well). A basic visual illustration of sound is the sine wave.

A sine wave a represents a pure tone which is a single frequency. This sounds something like the emergency broadcast signal or the sound the TV makes when the colored bars appear, a long sustained beep. All sound is made up of these types of waves at different frequencies superimposed on each other (this forms the waveform you see on your DAW when you are editing).

Analog recording such as to a magnetic tape or a lathe (for vinyl records) used a microphone as a transducer (makes the same wave in the air, but with electricity), and stored the wave information either magnetically or with actual grooves as on a record.

Digital audio is recorded differently. One can think of digital audio being captured and recorded by taking very fast snapshots of the waveform (on the order of more than 44000 snapshots per second). This process is called sampling.

This is where digital audio really shines. Once the waveform or “data” is captured in this digital form, it becomes very malleable when using a computer and mathematical formulas. This is how we gain the power to do non linear editing and apply convolution algorithms. Read the rest of this entry »

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How to Start Recording Audio on Your PC

In this multi-media, internet-dependent, YouTube-watching age, the ability to create your own audio has never been more important…nor so easy. If you have never produced audio before, now is the time to get started. And I do mean NOW, as in today! Most of you may not have the money necessary for a professional recording studio, which usually costs between $30 and $80 per hour! And that’s just fine. Because home recording is fun, can be profitable, and you probably have all the gear you’re going to need already. You’d be shocked at the quality you can get on home recordings produced this way, as long as you have a few bits of key knowledge.

The first step to getting started in recording your own voice for a podcast, video narration, voice-over, audio book, etc. is to have a computer (with a soundcard), a microphone, headphones/ear-buds, and recording software. Any PC (a Mac is still a personal computer isn’t it?) will do an excellent job as long as it was manufactured in the last decade. If you have a computer with a bunch of RAM, as well as a fast processor, things will, of course, be a bit faster and smoother. But again, you’d be surprised how much you can do with very little in the way of computing power. Audio does take up a fair amount of hard drive space (though nothing compared to video!), so keep that in mind as well. It will probably be helpful to have an external drive to back up your audio files from time-to-time.

A microphone is also a necessity for recording your own voice on the PC, but there are plenty to choose from that all work a bit differently. If you were to ask your local music store guy what kind of microphone (or “mic,” for short) you need for home recording, you’re likely to walk out of the store with hundreds of dollars less than you walked in with. But you may not need “that much car!” I strongly urge you to start out with a really cheap one; and I do mean cheap…as in those $5.00 plastic PC mics….uh huh! When you know what kind of quality is possible with an inexpensive mic, you will be much better off when it comes time to upgrade….if you ever decide you even NEED to upgrade. Read the rest of this entry »

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Audio Mixers to Mix Different Sounds and Enhancing Sound Effects

Sound mixers, also called as sound boards or sound consoles are the most general type of audio equipment in the audio production world. Each sound operator should know about the different sound mixers available and the correct way to use them. A sound mixer take two and even more signals, merges them together and offers more than one output signal. In addition to mixing signals, sound mixers enable to adjust levels, improve sound with effects and equalization, make monitor feeds as well as record various mixes.

Mixers are available in wide variety of designs and sizes from massive studio consoles to little portable units. Mixers are generally described through the total number of channels they sport. For instance, a 12-channel mixer includes 12 input channels. That is you can put in 12 individual input sources. You may also notice a specification like 24x4x2 that signifies 24 input channels, four subgroups and 2 output channels.

The mixers accessible are perfect for project as well as home studios or also on stage and in the recording studios. Many of the mixers present incredibly low-noise along with separate mic pre THD and are proficient enough to handle sound inputs varying from whisper to scream or even can easily handle hot line level signals devoid of any extra coloration. Some mixers provides a control room or phones source matrix, tape outputs, Master aux section along with EFX, a high volume headphone amplifier as well as balanced TRS and XLR outputs.

The most amazing aspect of audio mixers is that instead of unsealed, cheap potentiometers, many of audio mixers include co-molded pots that provide substantial impact relief and strain. A majority of the audio mixers available are the perfect pick for any type of situation that needs superior audio mixing, particularly where budget or/and space constraints are a problem. The audio mixers are beneficial for all kinds of recording purposes, including mixing the line output of more than one instrument amps in one mixer channel. Read the rest of this entry »

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