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A Powered Mixer is an advanced audio mixer, which provides a complete replacement for volume control. It lets you change the sound volume smoothly by simply rotating the mouse wheel or using keyboard hot keys. A powered mixer consists of an audio mixer with advanced volume controls, on-screen display, a scheduler, command line support, and the ability to store and recall unlimited presets.

An audio mixer is an electronic device which alters, routes, and transforms audio signals in a particular way. It is also known as a soundboard and helps in altering the beat, pitch or timbre of sound waves to create new notes and various types of music. Audio mixers allow sound waves from two different microphones to be blended together and be transmitted through one set of speakers.

An audio mixer usually has these components in them

• Input Jacks: These are required to plug in microphones and pre-amps. Jacks serve as the entry point for sound in the mixer.
• Basic Input Controls: Manual controls surround every input slot and are used to regulate the treble, pitch, bass of the input signals. These controls have to be regulated properly to avoid unnecessary noise from getting amplified.
• Channel Equalizers: These help in regulating the pitch of the music when is being played. It helps in correcting the minor problems in beats and helps in increasing the volume of the low pitch sounds to make them more audible.
• Routing Section: This routes the audio signals to the output devices like the recording device or speakers. The routing section is used to play the different parts of the music track from the different speakers. In a two speaker set-up sound is distributed between the left and right speakers. In a multi-speaker setup sound routed through a combination of all the speakers.
• Input and subgroup faders: These micro controls are used to adjust every channel of the audio. This makes minor adjustments possible. Adjustments are controlled through volume control sliders.

While a recording setup is incomplete without an audio mixer, a powered audio mixer is only a dream come true for a recording technician. Mixers can make the music of experienced professionals sound extraordinary and cover up flaws for budding artists. Hence it is very important to choose the correct powered mixer even if it is expensive as it may prove to be more cost-effective in the long term.

Timbre (or Sound Quality)

The goal of this article is to help develop knowledge of basic acoustic principles. This in turn will help you to understand, and eventually master, the basic techniques of sound engineering and recording. Each section has a theme that is first defined in technical terms and then commented on in practical terms in respect to audio equipment.

Definition of timbre
Timbre (pronounced /tam-ber’/) is a sound’s identity. This identity depends on the physical characteristics of the sound’s medium (the matter or substance that supports the sound). Let’s take an A at 440 Hertz produced at 60 decibels: we can immediately tell if the sound was emitted from a violin, saxophone, or piano. Yet, even though the instrument is different, it’s the same note and the same amplitude. The difference is in the sound production: string, air column, etc.. Plus, the sound isn’t generated by the same “tool”: a bow for violin strings, a reed and an air column for the sax, and felt covered hammers that strike the piano strings. It’s the different physical characteristics of the medium and the « tool » that determine the characteristic sound waves in each case. Later we will also see how a sound chamber adds another dimension to this definition.

Waveform

The most basic waveform is a sine wave (sinusoid). It could be considered the atom of sound. Pure sinusoidal sounds are rare ( tuning forks, drinking glasses being rubbed) and were considered to have strange powers over human behavior at one time. Most sounds that surround us are of a more complex nature.
This means that inside a sound, that we perceive as being unique, there is a superposition of many sine waves that have, in a way, fused together to become one sound. It’s the nature of this superposition itself that determines the resulting waveform and that is responsible for its timbre. This is called a spectrum.

Spectral Representation

There are many ways of graphically representing sound. For instructional purposes we have chosen to use a spectrogram for its clarity and simplicity.

Horizontally: time in seconds. vertically: frequency in Hertz. A sine wave (sinusoid) at 100 Hertz is represented by a horizontal line at a height corresponding to 100. A harmonic sound at 100 Hertz is represented by superimposed lines corresponding to sine waves of 100, 200, 300: n x 100 Hertz. The length of the lines represent the length of the sound.

Noise

Let’s imagine a case where all sine wave frequencies that are perceptible to the human ear (from 20 Hertz to 20 kHertz) and having the same amplitude, are “mixed” into one sound signal. We get what is called “white noise”, or in other words “hiss”. If the white noise is very short we would perceive it to be a kind of short percussive sound. Consonants belong to this category, in the same way that a sound medium that receives the attack of the “tool” which “kick-starts” it, produces as noise. This noise corresponds to the time it takes for the sound wave to stabilize and take its final form. The “rubbing” of a bow on a string is similar to a hissing sound, while a hammer hitting a piano string is similar to a percussive sound. These notions will be dealt with in greater depth when we get to envelopes and transients. In the case where a series of noise frequencies is contained between certain limits we will refer to them as noise bands.

If a zone is particularly swollen in energy, then we can speak about colored noise around that zone. Pink noise is white noise with a power density that decreases by 3 dB per octave.

Harmonic Sound

Having already highlighted the superimposed or complex aspect of sound, we are now going to focus on a specific category of frequencies in a sound spectrum: harmonics. A harmonic sound is a sound which contains sine waves that obey the mathematical law called the Fourier series. This law translates as follows: A complex periodic signal is made up of a certain number of component frequencies that are integers of the fundamental frequency.

An example of a harmonic sound: a sound at 100 Hertz in which the component waves are 100; 200; 300 ; 400 ; 500 ; 600 Hertz. The perceived pitch is the lowest frequency: 100 Hertz. The following component waves (2 x 100, 3 x 100, 4 x 100, etc.) are calculated on integers and are called harmonics. The lowest frequency, on which they are based, is called the fundamental. The number , or “rank”, of a harmonic is the integer by which the fundamental is multiplied. For example the 3rd harmonic would be the one at 300 Hz.

The pitch of a harmonic sound is easily perceptible to the ear, and these sounds usually have an “in tune” quality about them. That’s why melodic musical instruments are designed with the goal of producing harmonic spectrums.
Noises, like those we referred to earlier, are aperiodic signals. They are characteristic of percussion instruments for example.

The distribution of energy in the spectrum

Regions of relatively great intensity in a sound spectrum are called formants. In the case of a band of consecutive frequencies it is referred to as a formant zone between x and y Hertz. This distribution of energy plays an important role in the perception of timbre, as do the number of components in the spectrum, their distribution, and its regularity or non regularity.

EQing on a console

It’s the EQ section of a console that will allow us to tweak or correct timbre. Depending on the model, the EQ section is more or less sophisticated and offers different possibilities of adjustment. We won’t be dealing with simple high/low EQ knobs or switches that you can find on hi-fi amplifiers or entry level mixers which are only meant to adapt a sound to a specific listening area. We’re more concerned with the EQ controls that are found on small modern digital models or part of most major recording software. We must keep in mind that EQ is mainly used for one reason…to correct, and not in the hope of improving the recorded signal: you can never turn a mediocre recorded sound (due to bad placement of the mic or even the quality of the mic itself) into a great sound by just using EQ. Equalizers split the audible frequency range( 20 Hertz to 20 kHertz…) into many sub-ranges. Thus one generally talks about highs, medium highs, low mids, and lows. The first thing to do, then, before tweaking any knobs, is to determine in which frequency range the problem lies, then after that, the nature of the problem. Is it due to too much coloring that wasn’t detected during the recording process, a parasite due to the environment, or a masked effect due to the presence of other instruments…

What does it look like?

Equalizers are…harmonic and partial filters. Their specificity lies in the fact that they not only can get rid of component frequencies, but that they can also amplify chosen frequency zones. Of course, if there isn’t anything in the signal in that range, only hiss will be added! Good EQ sections generally have 4 bands. Each offers at least 2 controls: frequency adjustment and gain. These are called semi-parametric. There’s often a third setting called the bandwidth or “Q” which has the purpose of enlarging or tightening the frequency range (bandwidth) of the filter. When this 3rd control is present, the Equalizer is then called a parametric equalizer. Frequency adjustment will be tweakable between the upper and lower limits of the sub-range of the filter (with software these limits no longer exist!).

How to Modify Timbre

You must always keep in mind that all EQing on an instrument will be destructive with respect to the recorded sound, just as the latter is also, in many cases, an imperfect copy, of the original. So one must be careful! Before touching anything, think about what you want to accomplish with EQing: I want a “warmer” sound, I want to cut the bass, I want my instrument to stand out in the mix, I want to get rid of that annoying resonance that came from the studio…

How to set up a home recording studio can depend on the location, the walls, even what’s under and above the room. These are 4 tips I personally utilize in my own home studio, as well as my studio away from home. You’ve came to the perfect place to find more helpful information for your home recording studio whether you’re a rookie or a rookie veteran.

1. Save Your Money!

Do not spend your rent money on studio equipment like many people do. This is a very common problem because people feel the need to go after their dreams by risking all of their expenses. They do this with the hopes of getting all their money back in a short period of time. Very seldom does this situation turn out the way people want it to. Start small and finish big.

2. Where to Begin?

Keep it simple when you’re just beginning. Purchase a good computer if you don’t already have one. You need good music production software, a condenser microphone, and a mixer. This is all I needed to get started. More information on this below.

3. Food

A great way to attract people to your studio is a refrigerator. Yes, a mini or large refrigerator will keep your musicians and artists coming back to pay you. People will choose your studio over many others because of this great product that keeps people alive, food. Moreover, you don’t want to have everyone walking around your house, going into the kitchen, and waking people up in the middle of the night to get bottled water. Keep your refrigerator conveniently right next to your sitting area.

4. Water

Many public speakers drink room temperature water before they get up to speak. This same method can be used for your artists. To prevent the redundant throat clearing and overly excessive recording of tracks, drinking warm water is essential.

Bonus Tip

A bonus tip on how to set up a home recording studio is installing carpet in the room. This helps with eating up the sound waves so they don’t bounce all around the room back into your microphone.

How to set up a home recording studio can depend on the location, the walls, even what’s under and above the room. These are 4 tips I personally utilize in my own home studio, as well as my studio away from home. You’ve came to the perfect place to find more helpful information for your home recording studio whether you’re a rookie or a rookie veteran.

1. Save Your Money!

Do not spend your rent money on studio equipment like many people do. This is a very common problem because people feel the need to go after their dreams by risking all of their expenses. They do this with the hopes of getting all their money back in a short period of time. Very seldom does this situation turn out the way people want it to. Start small and finish big.

2. Where to Begin?

Keep it simple when you’re just beginning. Purchase a good computer if you don’t already have one. You need good music production software, a condenser microphone, and a mixer. This is all I needed to get started. More information on this below.

3. Food

A great way to attract people to your studio is a refrigerator. Yes, a mini or large refrigerator will keep your musicians and artists coming back to pay you. People will choose your studio over many others because of this great product that keeps people alive, food. Moreover, you don’t want to have everyone walking around your house, going into the kitchen, and waking people up in the middle of the night to get bottled water. Keep your refrigerator conveniently right next to your sitting area.

4. Water

Many public speakers drink room temperature water before they get up to speak. This same method can be used for your artists. To prevent the redundant throat clearing and overly excessive recording of tracks, drinking warm water is essential.

Bonus Tip

A bonus tip on how to set up a home recording studio is installing carpet in the room. This helps with eating up the sound waves so they don’t bounce all around the room back into your microphone.