macrae11 wrote:That's probably good for now. Now what?
gamblor wrote:So my question for you experts is: Where compression applies only to the dynamic range of a signal, how does this relate back to trying to achieve a perceived tone?
Drumwaiter wrote:The Attack and Release functions affect how quick the compressor acts when the signal goes above the threshold and how how quick the compressor let's go once the signal goes below the threshold respectively. So the slower the attack for example, the longer it takes for the compressor to grab the transient of the sound.
macrae11 wrote:Wow well ok, I'll put down a few, although I don't think I'm really the person to dispense technical wisdom on the topic.
FET
Optical
VCA
Vari-Mu
FET stands for Field Effect Transistor. Typically a fast comp/limiter with a musical sound. Originally designed to mimic the sound of tubes. Most famous- 1176
Optical, uses a light bulb or LED and a photo sensitive transistor to control the signal level. Very smooth sounding, slower response, can be tube(LA2A) or transistor(LA3A) based.
VCA, or Voltage Controlled Amplifier, is typically the fastest type of compressor, and also has more flexibility, and is generally cheaper to manufacture. DBX 160, and SSL compressors.
Vari-Mu, I don't really know how it works, something to do with tube bias/voltage/something or other. I don't have any experience with any, the only one I know of is the Manley Vari-Mu, although I think Fairchild compressors and their clones are Vari-Mu
Alain Benoit wrote:
Another popular topology is PMW (Pulse Width Modulation) based gain reduction scenario. Examples of this are the famous Cranesong STC-8 and the PYE compressor which I believe was the earliest commercial example of this.
The first rule is there are no rules. Every situation is different and you have to use your ears. That being said, I have some places that I seem to end up often. First off in the modern digital era, noise floor is not even remotely a concern for me. Like Matt was saying, I was pulling 40 dB on a lead vocal, and there was no noticeable increase in the noise floor in the mix. With 24 bit digital, a mediocre mic and a quiet room, it just doesn't come up.Christian LeBlanc wrote:Before we start talking about noise floors and creative uses of, and differences between, compression/limiting/gating, how about we start with common uses of compression? What instruments typically get more compression, and which get less? And for what reasons?
My understanding is that bass guitar, especially when locked in with the rhythm, will get more than most instruments.
Lead guitar may get a touch, while compression will vary from singer to singer, and from piece to piece. If one singer's volume levels are unintentionally all over the place, then a compressor is the best solution (other than, you know, vocal training and practice), right?
What about singers who appear to sing at almost a whisper, yet manage to get amplified quite loudly without horrible feedback from their microphones? What's going on "behind the scenes" to keep the noise floor at bay? Or is there something else at play? (as an example, I'm thinking of Julie Doiron, but anyone with 'quiet' vocals will do)
EDIT: I've spent years using a cheap microphone, and I completely forgot about the properties a good microphone can have: one that's balanced, designed to only pick up the singer, etc. So, it's probably safe to ignore this part of the question ;)
Christian LeBlanc wrote:Before we start talking about noise floors and creative uses of, and differences between, compression/limiting/gating, how about we start with common uses of compression? What instruments typically get more compression, and which get less? And for what reasons?
Christian LeBlanc wrote:My understanding is that bass guitar, especially when locked in with the rhythm, will get more than most instruments.
Lead guitar may get a touch, while compression will vary from singer to singer, and from piece to piece. If one singer's volume levels are unintentionally all over the place, then a compressor is the best solution (other than, you know, vocal training and practice), right?
Alain Benoit wrote:Another popular topology is PMW (Pulse Width Modulation) based gain reduction scenario. Examples of this are the famous Cranesong STC-8 and the PYE compressor which I believe was the earliest commercial example of this.
Drumwaiter wrote:Alain Benoit wrote:Another popular topology is PMW (Pulse Width Modulation) based gain reduction scenario. Examples of this are the famous Cranesong STC-8 and the PYE compressor which I believe was the earliest commercial example of this.
How does it work? I realise it may be over my head, but try me all the same.
Jef wrote:Shouldn't that read 'PWM'?
Alain Benoit wrote:Well first you'd have to understand signal modulation which i'm sure you kinda do on a basic level, then you'd have to grasp the basic concept of Pulse Width Modulation which I'm sure you could, then understand how it applies to audio, digital audio and Class "D" amplification. After all that you'd have to study basic semiconductor electronic concepts to understand how transistors are used as switches, then you'd have the tools you would need to get the basics of how compression is achieved through a PWM topology.
Alain Benoit wrote:PS- Did Larry get a hold of you re my shipment?
Alain Benoit wrote:Well first you'd have to understand signal modulation which i'm sure you kinda do on a basic level, then you'd have to grasp the basic concept of Pulse Width Modulation which I'm sure you could, then understand how it applies to audio, digital audio and Class "D" amplification. After all that you'd have to study basic semiconductor electronic concepts to understand how transistors are used as switches, then you'd have the tools you would need to get the basics of how compression is achieved through a PWM topology.
macrae11 wrote:Well I've got a grade school understanding of those topics. Can you connect the dots for us? And I thought the STC8 was pure Class A?
macrae11 wrote:That makes sense. So it's still an FET (which I assumed it was) doing the actual compression in a Class A signal path, but basing it off of the PWM Class D signal. Correct me if I'm wrong there, but it makes sense in my brain.
Alain Benoit wrote:PS- Did Larry get a hold of you re my shipment?
Until you can recognize compression and it's artifacts, it will be difficult to make decisions just like any other form of processing. I know many musicians and technicians who know what a compressor does, but can't "hear" it. Some will say that not hearing compression means it's doing a good job, but that's not what I'm getting at. I mean when a signal has been obviously compressed, can you hear it? When someone comments, 'Wow is that every compressed.' ...do you really hear it?gamblor wrote:Great topic Matt!
I’ve always known what compression physically does to a sound signal, but I find I have limited understanding of when, why, and how to use it. I find I’m able to grasp applications where I’m trying to clean up the dynamic range of a signal (usually on a vocal track) but I have a hard time relating it back to affecting the tone of an instrument (see the bass thread).
So my question for you experts is: Where compression applies only to the dynamic range of a signal, how does this relate back to trying to achieve a perceived tone?
Users browsing this forum: No registered users and 30 guests