What's "optical" compression?

[EddieRay]

And how is it different from that, uh, other kind?

[Massive Master]

Non-scientific version... Think of an optical compressor as a light that gets brighter when the signal gets louder. The brighter the light, the more compression is added (depending on the settings, of course).

A Voltage Controlled Amplifier (VCA) compressor uses the simple voltage to determine how hot the signal is.

VCA compression is typically faster and more accurate, but optical compression is arguably more "natural" and transparent sounding.

[earworm]

yeah,
so for example:; Optical compressors are more easy to use,
most of the time you just got a Ratio button (to choose how much compression you give) and you got a PRESETS button...

and thats it, in my opinion Optical compressors sound warmer and darker..
mhhh, but i only worked with ONE joemeek...no other Optical machines...

maybe this is a nice start for beginners.....simple compression,
and the Realease, attack and treshold shit is just for later....

anymore questions ?

[Fletcher]

An optical compressor [as was over simplified in a previous post] does indeed perform gain reduction control via a light source into a photo sensitive cell... as the light souce gets brighter, the photo sensitive cell tells the amplifiers to turn down the volume... hence less dynamic range, or what is known as a compressed signal.

There are all kinds of ways of performing compression in addition to an "optical gain reduction cell"... it can be done with a remote shutoff tube [also know as a "Delta-MU" or "Variable-MU" process], there are several different kinds of 'Voltage Controlled Attenuators" and "Voltage Controlled Amplifiers" as well as "FET limiting", "diode bridges", yada, yada, yada...

The fact of the matter is that the gain reduction cell, is only one of the myriad of variables that will contribute to the sound and reaction of a compressor. These processes really aren't more than advertising bullshit until you have a bunch of experience with a whole bunch of different units and processes.

As, if not more important than the gain reduction cell is the over all audio path, the analog electronics through which the audio actually travels. If this doesn't net you the tone and texture you're seeking for the music it matters not what the 'gain reduction cell' might be... cuz if it sounds like ass with nothin goin' on with the gain reduction cell, it's gonna sound like worse ass when you add gain reduction.

Before you fall victim to the avalanche of advertising buzz words used by the various marketing departments to move more steel... I'd highly recommend that you try a whole bunch of different units in your room on your music and determine which suit your style of music/engineering best... ain't no one box is the be-all / end-all for every situation... no matter what the big glossy ad in the magazine sez, nor what the mook at the Banjo Mart tells you.

Peace.

[acorec]

Originally Posted by Fletcher

An optical compressor [as was over simplified in a previous post] does indeed perform gain reduction control via a light source into a photo sensitive cell... as the light souce gets brighter, the photo sensitive cell tells the amplifiers to turn down the volume... hence less dynamic range, or what is known as a compressed signal.

There are all kinds of ways of performing compression in addition to an "optical gain reduction cell"... it can be done with a remote shutoff tube [also know as a "Delta-MU" or "Variable-MU" process], there are several different kinds of 'Voltage Controlled Attenuators" and "Voltage Controlled Amplifiers" as well as "FET limiting", "diode bridges", yada, yada, yada...

The fact of the matter is that the gain reduction cell, is only one of the myriad of variables that will contribute to the sound and reaction of a compressor. These processes really aren't more than advertising bullshit until you have a bunch of experience with a whole bunch of different units and processes.

As, if not more important than the gain reduction cell is the over all audio path, the analog electronics through which the audio actually travels. If this doesn't net you the tone and texture you're seeking for the music it matters not what the 'gain reduction cell' might be... cuz if it sounds like ass with nothin goin' on with the gain reduction cell, it's gonna sound like worse ass when you add gain reduction.

Before you fall victim to the avalanche of advertising buzz words used by the various marketing departments to move more steel... I'd highly recommend that you try a whole bunch of different units in your room on your music and determine which suit your style of music/engineering best... ain't no one box is the be-all / end-all for every situation... no matter what the big glossy ad in the magazine sez, nor what the mook at the Banjo Mart tells you.

Peace.

The guy at GC told me that the optical type of compressor was WAYY better sounding than the VCA kind. He had 100 optical compressors in stock, and no VCA compressors in stock. I think I should talk to someone else.............

[Fletcher]

He had 100 optical compressors in stock and no VCA compressors... sounds like the optical compressors are what weren't selling as he appears to be sold out on VCA compressors... the fact of the matter remains that the gain reduction cell is really only one component in a pretty complex piece of machinery... it's like trying to judge a car based solely on the transmission...

Best of luck with your search.

[dr.colossus]

fletcher, nice consice description of the workings of optical gain reduction.... can you tell us a little more about the workings of vari-mu..

[c7sus]

Hey Fletcher, I gotta couple questions about compression and limiting.

I'm recording a couple Martins (D-35L and D45L-Custom) with NT2, NTV, and a BLUE Cactus in various combinations and positions, through a Davisound TB-10 pre. Direct to a Darla20. I know, I know. I need to win Megabucks before I can upgrade to Lucid or Benchmark. I've tuned my room a bit with portable gobos, and am learning the room probably had less problems than I originally thought.

Anyway...........

I wanna maintain as much dynamic range as possible, but would really like some limiting. Both the guitars are cannons, especially the D-45. Even strung with lights it's got bass that doesn't quit. I don't expect "transparent" limiting, but the closer I can get the better.

What is your opinion of the Drawmer DL241, DL251, and the MX30???

And is the concept of "soft saturation" limiting a real deal or just marketing bullshit???