All Types Of Compressors Summarised!

Hi guys,

I know that many of you are not technically focused on the music production process, which is totally fine if you just start out as it just gets super overwhelming…

I know, I know…I’ve been there too, we all start somewhere…however, I believe that here and there you really should learn at least some super basics about the technical side of the music creation process, at least basic mixing, mastering, etc.

As I started to build more and more resources for people like you, starting out composers and music producers, I recently came across a super confusing topic: compression – and to be more precise: different types of compressors…there are actually six of them!

So I thought: Well, I’ll write a straight forward guide about it…so here it is…if YOU are the kind of person who still is confused what a FET compressor is, or why it is sometimes better to use an optical compressor, instead of a VCA, the following lines give you a basic overview…

First things first: A compressor is a tool that tames peaks (reduces the dynamics) of an incoming signal to allow you to have an overall more balanced-out performance. There are many scenarios why and how you can use a compressor, however, the main purpose (in the 50s) was to create a tool that helped the recording engineers to not ride the volume faders all the time during a performance, as music can be extremely dynamic.

As I have said before, during the past 70 years the recording industry came with many different types of compressors…and these are:

VCA – Voltage Controlled Amplifier

  • The VCA compressors are the most versatile of all types of compressors
  • Most used type of compression
  • They are fast, smooth and are not very colorful, thus don’t change the sound characteristics too much
  • Popular choice for bus compression and mastering
  • Have all typical controls of dynamic processors: attack, release, threshold, ratio, and knee
  • Most famous VCAs are the SSL & Neve channel strips compressors, the dbx 160A, and the API 2500

Technical information:

The electrical circuit is split into two paths:

(1) Detector path: When a certain voltage is reached, the compressor turns down the signal, thus controls the compression effect

(2) Output path: Is what you hear in the end

Opto / Optical Compression

  • Used for vocals, lead instruments, bass and rounding out a performance (think of a long-term event)
  • Sound characteristics: Smooth, natural and musical sound
  • Can handle more gain reduction, yet still sounding natural, as the attack and release times are slower overall
  • Famous Optical Compressors: LA2A & Tube Tech CL1B

Technical information:

  • Compression depends on light (light-dependent resistors)
  • The audio signal feeds a light element which operates through a light-sensitive resistor
  • Resistor acts like a pipe: Gain says how much is going into the pipe and peak reduction says how much is going out of the pipe, or in other words, the more resistance a.k.a peak reduction, the more compression overall
  • Optical compressors add color as there are many different types of light sources and resistors available

FET Compression

  • Best use for hard peak limiting tasks (super-fast attack & release times)
  • If you want something „in your face“ like vocals, you’ll better grab a FET compressor
  • In general not a good fit on the master bus
  • They add color to the source material
  • Most famous: Urei 1176

Technical information:

  • The electrical circuit is based on transistors (transmitter + resistors) and operates with the electrical field in addition to voltage (not the same as VCA)

Vari-Mu (Variable-Mu by Manley or originally Delta-Mu)

  • Adds glue and is used not for dynamic control in first place
  • Gentle type of compression (mix bus)
  • Sounds like a soft-knee effect
  • Not suitable for an aggressive type of sound
  • Adds color without even limiting the material (tubes)
  • The sound quality is smooth, rich, thick & creamy
  • Transients are treated in a musical way
  • Speed response is the slowest compared to the other types of compressors
  • Can handle more gain reduction before unwanted artifacts occur
  • Most famous: Fairchild 660 & 670

Technical information:

  • Compressors are based on tubes
  • While Opto-Compressors can use tubes for color, Vari-Mu compressors use tubes to tame dynamics
  • The ratio increases as you push the unit harder, so this technique sounds musical and pleasing to our ears


Diode-Bridge Compression

  • Most colorful compression of all, as a diode itself adds colorful distortion
  • The Neve 2264 500 series unit is one famous example of diode-bridge compression

PWM - Pulse Width Modulator

  • A pulse width modulator circuit creates almost no artifacts, thus no color (the cleanest compressors of all)
  • Extremely difficult to build, thus extremely rare
  • Modern unit of a PWM compressor: Great River PWM 501

Well, I didn’t cover how you use a compressor, however, it’s another topic on another day. But for now, you know that a compressor is not always the same compressor.

Use this guide as a reference for your next projects and productions. Get familiar with those different types, as you are NOT confused anymore :wink:

One last more thing: Don’t forget that the world has changed quite a bit and as a music creator, you are responsible for YOUR MUSIC to sound as good as it possibly could, as there are not always budgets to book a seasoned engineer like me for example to mix your track. So from time to time, it would be beneficial to learn some little technical hacks to improve your music.

I hope that helps!

To your success,
Alexey :slight_smile:


Wow, this is an amazing post Alexey!! :smiley:
Can I publish this on my website/blog with your permission? Of course I will include links to your website/youtube channel and give you full credit as the author. :slight_smile:

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Sure Mikael, go ahead! I think I have used 4-5 sources to get done, but all of them are just long text files and after 2 minutes you don’t want to read anymore, too technical…I wanted to keep it as simple as possible :slight_smile:

Thank you :pray:

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Thanks, and btw, perhaps you should do a “compression tips” video on your YouTube channel. Just a tip, but I think many producers want to learn about this as it is one of the most fundamental FX for music! :wink:

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Yeah, it’s already on my list. There are a couple of topics before that, however, you are absolutely right, compression is an extremely important tool for music, technical wise and sound wise too.

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This is an amazingly detailed outline of compressors - thank you very useful

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I just re-posted it as a blog post on my website, included a link to your YouTube channel and Free E-book! :slight_smile:

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Awesome post man! This will definitely help people who are starting out. Hopefully this will give people the foundation to experiment with compression.

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Thank you a lot!

I think it’s not only interesting for beginners but for intermediates too!

Let’s be honest…do you really use all of them, at least VCA, FET, Vari & Opto?

FET for example, I don’t use super often…I don’t produce or mix super aggressive music, so FET would be the first go-to, as described.

Vari, as I said, is more glue rather than straight forward compression. The only Vari that I do have is the one from Native Instruments, however, I don’t use it. For glue I love the Drawner 73 and Tape. I don’t miss a “tube” sound, as I have other options to simulate that.

My go-to are SSL & Neve as my VCAs, Kotelnikov is heaven as well.

Opto go-to is Supercharger by NI…GT is awesome as well, it’s something I have never heard before beside “Punish” by Heavyocity. I am looking for the Softube bundle, all there plugins are just high-end. However, it’s still important to understand that having more plugins doesn’t necessary mean your music will be better after purchasing. My term for that is: I am a mixing minimalist, meaning I only do as much as I need to feature the music, not inserting 20 plugins in a row thinking it will become 20x better. (Another topic, another day…) :slight_smile:


I personally use all of them but that’s only because my background is in pop and rock production. I moved to orchestral sampling about 8 years ago, so I do both.

In terms of samples you don’t really need to compress them unless your making effects.

This post is great in terms of knowing what they all do and the differences, but practically it’s a little less straightforward.

But this would come in useful if you were employing live musicians for instance.

Some good examples would be using an opto compressor such as an LA2A on strings or woodwinds… this would add higher harmonic as the LA2A is also tube based. These bring the highs out really well while keeping the signal clean.

FET style compressors would be great for Horn/Brass players as they ad a lot of low mids which would strengthen the tonality. FET comps are also slower attack compressors which is why a lot of low instruments and male vocals are put through them. Snares also sound great as they compress the tail of the signal more than the actual initial transient

Those two are the only ones I’d use on orchestral tracks. But this is just theoretical.

It’s a lot of fun just messing around with compressors though as they can change the EQ curve slightly of your tracks, so stacking them and in your DAW and using them subtly really can change the flavour of a track really well.


Oh I did not know what kind of compressor was in Supercharger, but I do know I love the sound of it, and it is so handy to have that nice saturation in the same plugin! :wink:

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Which is your favorite FET compressor? Especially for bold low brass, which I like to beef up. :slight_smile:

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lol this is a big subject. I’ll try to keep it short.

Typically in the analog world I’d probably grab a distress or for low brass. But you need to be gentle with them as they live up to their name :joy:

Typically for an overall well rounded compressor I used to grab the DBX 160… it had a little more of a smooth mid range but hits pretty hard. Think it’s a hard knee compressor and they also brought out a soft knee later which I’m not as familiar with… great for limiting and bringing up those lows you might like.

In the box these are the compressors I grab for this type of job.

Scheps omni channel - has a FET that’s designed after a neve, but I personally think it behaved a bit like an 1176 right at the top of the threshold which I think is intentional for drums. This is actually everywhere on my tracks… sounds incredible. It’s almost like my secret weapon.

Reneisance comp - this little beastie is industry standard and also acts as an expanded. It’s quite colourless and bites hard (along with the Axx)

NI - 76A compressor. Most people would have this if they got the NI bundle. It’s really great and turns it’s hand to a lot of different applications.

This ones a bit of a wild card. But it does act as a compressor in a way.

J37 Tape - I mostly use this on outputs to give that tape feeling to my tracks but I also use it on bass instruments because it hard clips your signal depending on how hot your signal is coming into it, exactly like the original 1960s j37. If you stick a gain plugin before it and after it you can increase the input so that the plugin works harder and then decrease the gain afterwards by the same ammount so that the rape bus is working at its optimum… (peaking around 0 rms, spiking between -3 and -8). Or pus it further for an even more saturated and compressed sound. Really cool tip for thick and super saturated tracks.

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Thanks Geoff! :slight_smile:

I am considering to get either the Soundtoys Bundle or Softube Bundle to expand my music production toolkit. They both have some great compressors/limiters in these bundles, so hard to choose. :stuck_out_tongue:

Tape compression is something I haven’t really tried yet, so that is very interesting.

I’ve been looking at the tiny plate from sound toys but I’ve not really used the. A lot so I can’t say much about them. I have however used the soft tube stuff and it’s very good. I went back to using my Waves stuff just because I prefer the sound. You get a little less transparency on the saturation stuff with waves… which I prefer. Plus I can’t get enough of the reneissance stuff from waves. If I were to have only one bundle it would be the waves reneissance.

Once you go tape, there’s no going back :stuck_out_tongue:

Here’s an excellent video on mixing with real tape that you can hear what I was talking about… used to use real tape in college which was fun… back then I could never get the input right so I always failed haha.

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Regarding Tape Emulation plugins, I want to find a good all-rounder for group tracks and master bus. Just that analog glue and “taming of the highs”. Softube’s “Tape” looks really nice for this purpose, yes?

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100% Softubes Tape Plugin!

It doesn’t give you like an extreme sound change compared to the others I have used, however, the overall purpose for me wasn’t to change the sound, the purpose is to tame dynamics, make it a little bit more compact and creamy. For that purpose Tape is your go-to. :slight_smile:


Nice to hear! I think I will go for the Softube Bundle, but I see they have several “volumes” of bundles so I need to consider which FX I really want :wink:

Thanks for this. I am one of those new in music production people. Now I know what the different colors of compressors in Logic mean. I really didn’t understand. Just last night, I considered purchasing several of the things that you guys were discussing below. But, I didn’t because I told myself that I was just buying them just because they were on sale on the Waves website, and once I purchased them they would just sit there Un-used because I wouldn’t know how to used them. For example, I currently have the following Un-used items on my external drive:

Fab filter Suite- (I do use Q3 but I’m sure not correct)
Vienna Suite- never used it
Vienna Amir Pro- never used
All of the plugins in Logic ( I use them but I don’t know what I’m doing. I just turn knobs until I hear something that I like. Most of the time I just end up taking it off of the bus because it doesn’t improve the sound. If I do happen to get something to sound good, I am never able to recreate it because I really don’t know what I did to get there in the first place.)


I would love to help you out, really. Unfortunately I am not prepared to offer you a music production course that would cover all of that. However, here are some really good sites you need to subscribe, as I know that those folks will be good for you :slight_smile:

• Produce Like A Pro (easy going with Stuart)

• MixBusTV (Advanced…maybe too early for you…however, David is a beast)

• InTheMix (a young gun, but definitely a nice guy, a good fit for your level I think)

• RecordingRevolution with brother Graham (a had really great talks with him over the last months and I believe what he does is just outstanding, in general a guy everyone should look up to! For you the number one of this list!)

• Joe Gilder (Home Studio Corner), great guy with great humour and is a really good teacher in my eyes. Check him out!

• And of course: @Mikael (do you have a small course, in your arsenal, to teach @jonnelson1988?)

• And last but not least: if you haven’t already, hear is my channel: I don’t go all-in with YouTube at the moment, however, here and there will be something interesting for you as well I believe… (reached 50 subs today…woop-woop!) :v: :muscle:

Hope that helps,
Alexey :slight_smile:

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