The Fractal Wiki has some good stuff here, mostly off the manual. I'm going to re-post it at end/below.
But first, I'll start...we generally know what compressors do (squash existing dynamic range - sometimes too much!)....add sustain...focus the sound...
...People put them in front of amps (usually pedal compressors) for a few reasons...get the country chicken' picking thing going - where all the picked notes are basically even in volume... or to increase lead or chord sustain....or squash cleans good (like the 80's all over again)...and back in the 70's, Lowell George of Little Feat used two studio-grade compressors (UA 1176s) in series to get that endless slide sustain thing happening into his Dumble...
...In the recording studio, compressors for guitars are usually put after the mic preamp coming off the cab for a few reasons....one is to tame the signal transients when recording -- leveling out the highs and lows...the other is to mildly compress the incoming signal (like 2:1 ratio ) but then turn up the compressor's output UP to slam the the signal going onto the recorded track, to make guitars sound more punchy....
...And of course compressors are usually heavily used on recorded bass guitars (sometimes compressing them two or three times!)....or across stereo buss mixes to punch up the final sound and "glue" all the instruments together (as one example, that Universal Audio SSL stereo buss compressor plug-in is fantastic, I can use it on everything coming out my monitors -- it makes everything sound better and never sounds like a compressor working!)...
So the major types/food groups of compressors are VCA, Optical, FET, and VariMu. One good explanation is here, for the Logic Plug-in emulations. I found this pretty useful detailed Logic Compressor comparison cheat sheet here as well. (Maybe we can make one for the Fractal compressor models?)
From what I can tell, Cliff has not tried to faithfully model specific iconic compressor brands, but instead taken their specs and made them wider, and more versatile. So the original's "DNA" is in there for the food group type, but you make his cool Fractal compressor versions do things the original real ones can't.
So - it would be nice to know, "if we wanted to emulate a (name of iconic compressor here), which Fractal compressor block type should we choose?... For the:
1176? This is an FET FeedBack (not FeedForward) type compressor....(so it can't be the Studio compressor since the Axe-III manual says that the Studio type is a FeedForward...so, is this the new Analog one we can use for an 1176?...)
Fairchild 670? (Tube, or Optical?...)
LA-2A? - (Optical!)
dbx160? It's a VCA...
SSL Stereo Buss? It's a VCA too...
Manley VariMu? Tube type?
Orange Squeezer? (Pedal 1 of course!)
DynaComp? (Pedal 1 again!)
Keeley Compressor? (Pedal 2 perhaps?...)
From Wiki:
Pedal Compressor 1 and 2 – "Pedal 2" uses a different algorithm which is smoother and pumps less than "Pedal 1". CPU usage by both types is much less than the "Studio" type
Dynamics Processor – allows compression or expansion with a single control. When set to negative values, the block compresses the signal. When set to positive values, the block expands the signal
Optical Compressor – based on classic optical tube compressors, famed for their smooth sound. Use it before the Amp block to smooth out your licks and increase sustain, use it after the Amp block for instant “Hit Record” sound
Tube Compressor – based on classic tube compressors like the Altec Lansing 436C. Since this type uses “variable mu” processing it may add subtle, and possibly desirable, distortion to the audio
Analog Compressor – natural soft-knee response, capturing the vibe of the classic compressors of the 70s and 80s
(circa Axe-Fx II) "Optical 1 uses a full-wave rectifier as a detector (peak detector). Optical 2 uses a true RMS detector. The LA-2A and many other compressors use rectifiers as detectors because it's easy and simple. Technically true-RMS detectors are "better" but they are difficult to implement in analog hardware. Whether or not true-RMS is better in actual real-world applications is debatable. There are those that claim that true-RMS detectors more closely replicate the natural compression behavior of the human auditory system. Peak detectors respond more rapidly to transients while RMS detectors have a smoother behavior. The only way to know which you like better is to try them." source
(About the combined optical compressor) @FractalAudio said "It's not an "LA-2A" but it can sound like one. It's a generic optical compressor that can be adjusted to sound like a variety of compressors. It has adjustable attack, release and compression." source" The LA-2A, CL1B, et. al. are high-end studio compressors that use optical circuits." source
So - thought I would get a conversation to further the group knowledge going here! Am NOT a technical expert on this stuff. But I know that the sound of compression is THE sound of rock guitar since the late 60's and we could all benefit from understanding these awesome tools Cliff made for us even better...
So what Fractal compressor types do you use to emulate what famed compressors? (Maybe with luck Cliff will chime in sometime to illuminate further for us)...
But first, I'll start...we generally know what compressors do (squash existing dynamic range - sometimes too much!)....add sustain...focus the sound...
...People put them in front of amps (usually pedal compressors) for a few reasons...get the country chicken' picking thing going - where all the picked notes are basically even in volume... or to increase lead or chord sustain....or squash cleans good (like the 80's all over again)...and back in the 70's, Lowell George of Little Feat used two studio-grade compressors (UA 1176s) in series to get that endless slide sustain thing happening into his Dumble...
...In the recording studio, compressors for guitars are usually put after the mic preamp coming off the cab for a few reasons....one is to tame the signal transients when recording -- leveling out the highs and lows...the other is to mildly compress the incoming signal (like 2:1 ratio ) but then turn up the compressor's output UP to slam the the signal going onto the recorded track, to make guitars sound more punchy....
...And of course compressors are usually heavily used on recorded bass guitars (sometimes compressing them two or three times!)....or across stereo buss mixes to punch up the final sound and "glue" all the instruments together (as one example, that Universal Audio SSL stereo buss compressor plug-in is fantastic, I can use it on everything coming out my monitors -- it makes everything sound better and never sounds like a compressor working!)...
So the major types/food groups of compressors are VCA, Optical, FET, and VariMu. One good explanation is here, for the Logic Plug-in emulations. I found this pretty useful detailed Logic Compressor comparison cheat sheet here as well. (Maybe we can make one for the Fractal compressor models?)
From what I can tell, Cliff has not tried to faithfully model specific iconic compressor brands, but instead taken their specs and made them wider, and more versatile. So the original's "DNA" is in there for the food group type, but you make his cool Fractal compressor versions do things the original real ones can't.
So - it would be nice to know, "if we wanted to emulate a (name of iconic compressor here), which Fractal compressor block type should we choose?... For the:
1176? This is an FET FeedBack (not FeedForward) type compressor....(so it can't be the Studio compressor since the Axe-III manual says that the Studio type is a FeedForward...so, is this the new Analog one we can use for an 1176?...)
Fairchild 670? (Tube, or Optical?...)
LA-2A? - (Optical!)
dbx160? It's a VCA...
SSL Stereo Buss? It's a VCA too...
Manley VariMu? Tube type?
Orange Squeezer? (Pedal 1 of course!)
DynaComp? (Pedal 1 again!)
Keeley Compressor? (Pedal 2 perhaps?...)
From Wiki:
Pedal Compressor 1 and 2 – "Pedal 2" uses a different algorithm which is smoother and pumps less than "Pedal 1". CPU usage by both types is much less than the "Studio" type
Dynamics Processor – allows compression or expansion with a single control. When set to negative values, the block compresses the signal. When set to positive values, the block expands the signal
Optical Compressor – based on classic optical tube compressors, famed for their smooth sound. Use it before the Amp block to smooth out your licks and increase sustain, use it after the Amp block for instant “Hit Record” sound
Tube Compressor – based on classic tube compressors like the Altec Lansing 436C. Since this type uses “variable mu” processing it may add subtle, and possibly desirable, distortion to the audio
Analog Compressor – natural soft-knee response, capturing the vibe of the classic compressors of the 70s and 80s
(circa Axe-Fx II) "Optical 1 uses a full-wave rectifier as a detector (peak detector). Optical 2 uses a true RMS detector. The LA-2A and many other compressors use rectifiers as detectors because it's easy and simple. Technically true-RMS detectors are "better" but they are difficult to implement in analog hardware. Whether or not true-RMS is better in actual real-world applications is debatable. There are those that claim that true-RMS detectors more closely replicate the natural compression behavior of the human auditory system. Peak detectors respond more rapidly to transients while RMS detectors have a smoother behavior. The only way to know which you like better is to try them." source
(About the combined optical compressor) @FractalAudio said "It's not an "LA-2A" but it can sound like one. It's a generic optical compressor that can be adjusted to sound like a variety of compressors. It has adjustable attack, release and compression." source" The LA-2A, CL1B, et. al. are high-end studio compressors that use optical circuits." source
So - thought I would get a conversation to further the group knowledge going here! Am NOT a technical expert on this stuff. But I know that the sound of compression is THE sound of rock guitar since the late 60's and we could all benefit from understanding these awesome tools Cliff made for us even better...
So what Fractal compressor types do you use to emulate what famed compressors? (Maybe with luck Cliff will chime in sometime to illuminate further for us)...
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