Compression

[Ozzyhardstyler]

Hi,

I have started using a Opto Compressor, the problem is i'm used to having Threshold, Ratio, Attack & Release & makeup gain.
This one has only got Input, Output, Attack, Release & Compression.

I have a basic knowledge of compression like Threshold brings the volume down in -db's and the ratio once it goes above the threshold turns the volume down.

My question though it might sound stupid:
Is Compression the actual Threshold, and input the makeup gain?

Thanks
Mark D

[TheRavestyler]

Threshold – how loud the signal has to be before compression is applied.
Make-Up Gain – allows you to boost the compressed signal. as compression often attenuates the signal significantly.

Compression is the process of lessening the dynamic range between the loudest and quietest parts of an audio signal. This is done by boosting the quieter signals and attenuating the louder signals.

maybe this answered ur question ?

[Ozzyhardstyler]

Yes but it doesn't actually say Thershold and makeup gain that's what my question is.
What parts will they be on the compressor?
here is an image of the compressor I am using.

[zanshi]

you get a nice intro right here (incl audio examples):
http://audio.tutsplus.com/tutorials/mix ... h_index=14

Compression is one of those studio processes that is all too often taken for granted and not used to its full potential. Today’s producers think nothing of inserting compressors on every single channel of their DAW when mixing, but old school engineers had to learn to make the most of only a few units of compression—and this made us learn them inside out.

What is Compression?
Compression is the process of lessening the dynamic range between the loudest and quietest parts of an audio signal. This is done by boosting the quieter signals and attenuating the louder signals. The controls you are given to set up a compressor are usually:
Threshold - how loud the signal has to be before compression is applied.
Ratio – how much compression is applied. For example, if the compression ratio is set for 6:1, the input signal will have to cross the threshold by 6 dB for the output level to increase by 1dB.
Attack – how quickly the compressor starts to work.
Release – how soon after the signal dips below the threshold the compressor stops.
Knee – sets how the compressor reacts to signals once the threshold is passed. Hard Knee settings mean it clamps the signal straight away, and Soft Knee means the compression kicks in more gently as the signal goes further past the threshold.
Make-Up Gain – allows you to boost the compressed signal. as compression often attenuates the signal significantly.
Output – allows you to boost or attenuate the level of the signal output from the compressor.

Compression Types
Compressors come in various different flavors. These are used by engineers for different tasks and some sound far better in certain situations than others.

VCA Compression
Voltage Controlled Amplifier compressors use an integrated circuit to give very precise control. They are less colored and suffer from very few side effects like distortion, which make them ideal for lots of different tasks. The dBx 160 is a VCA compressor.

Opto Compression
Opto, meaning optical, describes the light sensitive circuits that control the compression amount in opto compressors. They often react more slowly than other compressor types, but this can be desirable. The famed Teletronix LA2A is an optical compressor that many producers swear by for vocals and mix bus compression. The LA2A is also a ‘leveling amplifier’ — which means it is working nearly all the time, not just when a threshold is reached.

FET Compression
Field Effect Compressors use transistors to emulate a valve sound with more reliability, but with a higher signal to noise ratio. They are popular for vocals and great for drum compression. The Urei 1176 is a FET compressor.

Valve Compression
Valve compressors work in one of the three ways described above, but use valves in the amplifier circuit to get that ‘creamy’ sound. The LA2A, which is an opto compressor, uses valves.

How Set Up a Compressor

1. 1. Whether you’re using a hardware compressor or a plug-in, setting up works the same way. Insert the compressor on the channel you want to compress.
   2. Adjust the threshold until the peaks in the signal are pushing over the threshold and triggering the compressor. Unless, of course, you really want to clamp something—like a live bass maybe—in this case it can work to make it push over the threshold all the time.
   3. Set the Ratio to suit the material. Bass guitars sound good at 4:1, drums at 2:1, vocals also at 2:1 and electric guitars anywhere from 2:1 to 6:1.
   4. The Ratio and Threshold work together. Adjust them together and see how they affect the output.
   5. The attack and release controls shape how the compressor reacts. A fast attack would be useful for a rapper or anything that has sudden peaks early in the signal. Slower attack times suit mastering uses and buss compression.
   6. The release control can really affect the sound of the compressor. Short release times cause the compressor to sound like it’s working hard, but long release times sound more natural.
   7. Use the make-up gain and output control to sit the signal back into the mix without adding any unnecessary noise.
   8. Setting the hard/soft knee would depend on the material. Hard knee works well for drums, bass and percussive stuff. Soft knee is more transparent and better for vocals and some guitar parts.
   9. Look-ahead. Plug-in compressors often have this feature. It uses a slight time delay on the whole song to give the compressor a sneak preview of what’s coming. This allows it to catch all the peaks in the smoothest possible way. It can sometimes cause the compressor to lose its ‘character’ so don’t use it by default—only if necessary.
   For every rule about setting up compressors, there’s someone who has broken the rules and made a great sounding record, so experiment.
   A final word of warning—compressing on the way to your recording format, be it tape or hard disk—can’t be undone. Use compression sparingly whilst recording. Save it for the mix until you’ve got enough experience to know you’re not overdoing it.

[Ozzyhardstyler]

Thanks would the compression on the pic I posted be the Threshold, and the output the makeup gain?

[malicious_kode]

Just out of curiosity, did anyone actually read the question before replying?

(I did.)

My question though it might sound stupid:
Is Compression the actual Threshold, and input the makeup gain?

It would seem that the knob labelled Compression is indeed the control referred to on most other devices as Threshold. Dunno why they wouldn't just call it Threshold though, as a control for "Compression" seems more likely to me to be indicative of that for Ratio, but as there is already a Ratio control, Threshold is the logical conclusion. Input adjusts the incoming (pre-compression) signal. Output would be the Makeup (post-compression) signal.

[Ozzyhardstyler]

Just out of curiosity, did anyone actually read the question before replying?

(I did.)

My question though it might sound stupid:
Is Compression the actual Threshold, and input the makeup gain?

It would seem that the knob labelled Compression is indeed the control referred to on most other devices as Threshold. Dunno why they wouldn't just call it Threshold though, as a control for "Compression" seems more likely to me to be indicative of that for Ratio, but as there is already a Ratio control, Threshold is the logical conclusion. Input adjusts the incoming (pre-compression) signal. Output would be the Makeup (post-compression) signal.

Exactly what I wanted, thank you