What does vari-mu stand for?

Variable-gain compression
Vari-mu, which is just shorthand. Variable-gain compression, which is perhaps confusingly similar to variable-gain amplification or voltage-controlled amplification (VCA). More on VCA compressors here. Tube compression, though any compressor with tubes in its design could be called a “tube compressor”.

What is vari-mu compressor good for?

This type of compressor works best on the master/group bus as it glues sounds together into a single homogeneous sound. It can be used to add warmth and thickness to a sound. The most famous Vari-Mu compressor is the Fairchild 670.

How does a tube compressor work?

Tube compressors achieve compression by re-biasing the tube to control the gain reduction. This characteristically imparts a warm smoothness and slight harmonic distortion to the sound.

What is Variable MU compressor?

An audio compressor that employs a valve (tube) as the variable audio attenuator. Mu is an engineering term for gain, so this is a variable-gain compressor. In essence, the side-chain signal continuously adjusts the bias o the valve to alter its gain appropriately.

What is the difference between FET and VCA compressor?

VCA compression is meant for clean, transparent mixing where you want control over a large range of parameters. FET compresion is better suited for aggressive and heavy sounds like electric guitar and drums.

What is opto compression?

An Optical Compressor (or Opto-Compressor) uses a light source to control how much gain reduction is applied. The speed of light is extremely fast, but an Opto compressor is actually quite slow and smooth.

What is bias on a compressor?

Variable-bias compressors have a rich sound, featuring a soft knee, progressive and musical saturation, and relaxed timings. Their ability to compress transparently makes them particularly desirable for use on mix busses or in mastering.

What is MU of a tube?

A Mu of 25 means that voltage of 1 Volt applied to grid of a vacuum tube is amplifier 25 times and increases to 25 Volt on anode of the tube. For triodes, Mu (voltage gain) is the most important parameter to measure and is the parameter that makes the biggest impact on sound quality of amplifier.

What is VCA compression?

VCA Compression This is arguably the most commonly used compressor phenotype in the corporeal universe. It tends to sport all the controls you’re used to seeing (attack, release, threshold, ratio, and sometimes knee). VCA stands for “Voltage Controlled Amplifier,” a type of mechanism found in many musical applications.

What compressors are VCA?

A VCA (voltage-controlled amplifier) compressor is an analog compressor that utilizes a VCA control to apply compression. The input signal is split through an integrated circuit into a detector path (to control the VCA compression) and an output path.

What does FET stand for in compressors?

FET compressors are commonly the choice for parallel processing because of the aggression and vibe they add. They work by passing audio through a “field effect transistor” for their gain control (hence the abbreviation FET).

Why do compressors sound different?

Most classic analog compressors have unique shapes to these transitions which gave them very distinctive sounds, and that’s why many software compressors that aren’t modeled after that analog circuitry sound different.

What is squeeze compression?

Squeeze refers to the threshold of the compressor. The compressor only starts to compress when it hits its threshold, so if you set Squeeze at -30dB, it means the compressor will not engage when the signal level is below that.

What does GM mean for a tube?

Since this “conductance” is from the input to the output circuits of the tube, and goes “across” the tube, it is called “transconductance” or “mutual conductance”. Since “G” is the symbol used in electronics for conductance, this explains the use of the symbol “Gm”.

What is vacuum tube GM?

The formula for transconductance or Gm of a vacuum tube is as follows. Gm=delta Ia ÷ delta Vg. This is the difference in plate current divided by the difference in grid voltage that produced it. So in simpler terms it would be plate current divided by grid voltage.