An Intresting Read about GAIN STAGING from Chuck At Bose.
It helped me understand better. maybe it will help one of you too
OK – Gain, in the context of a highly transparent audio system. To some, the following will seem like long-winded nit picking. If you’re perfectly happy with the sound that you’re producing with your systems, no matter how you’re getting it, then by all means don’t fix what ain’t broken. To others, it may be perceived as overly simplified. Please know that I’m not trying to ‘dumb it down’. I offer this attempt at explaining how audio systems work, in the most non-technical language that I can muster, to anyone who wishes to learn how to coax the absolute best possible results from their audio system. Your critique, the measure of my success/failure, is welcome and appreciated…
Let’s begin at The Source.
Imagine a tiny wave riding down a wire at the speed of light. We know what caused the wave and that it was beautiful. We want to somehow use the tiny wave to move the air around us with sufficient energy and uniformity so that everyone in the space can hear that beautiful source clearly. When we hear the sound clearly, we may smile and leave it alone, or wince and choose to modify some of its traits, but ideally, any gizmos that we use along the way shouldn't impose unwanted changes...
Some examples of simple sources:
Voice > mic > wire >
Instrument > wire >
Instrument > mic/pickup > wire >
Instrument > pickup > wire > mic'd amp > wire >
Recorded sound > recorded sound player > wire >
Some examples of sources which are more complex:
Voice > mic > wire > effects/mixer > wire >
Instrument > mic and/or pickup > wire > effects/mixer > wire >
Recorded sound > recorded sound player > wire > effects/mixer > wire >
The Gizmos.
For the past several decades, we humans have strived to make our beautiful sources louder and clearer with the goesintas, comesoutas, amps and speakers of (cue announcer voice) THE SOUND SYSTEM. The mere mention of it strikes fear into the hearts of many, but it can really be quite friendly and effective if we understand how to make a few sensible adjustments to help it perform at its best. To those of us wanting only to produce and control what is heard by us and our audiences, these gizmos are nothing more or less than a series of controlled steps toward making our wave bigger. These steps are commonly referred to as gain stages by tech-head geeks like me. Let's look at the path that our tiny wave follows through an audio system:
Source – Our tiny wave. Its output connects to a gizmo with knobs and meters on it...
Trim – First stage of the gizmo. Makes the tiny wave bigger, just the right size for the gizmo to do its best work...
Level – Second stage of the gizmo. Brings the now bigger wave into balance with others that are sharing the gizmo and to where their mix creates a level that makes the next stage happy...
Master – Combines all of these bigger waves and sends them to the next stage at a level that makes it happy...
Power Amp – A last big boost, by far the biggest of all, so big that it can make a loudspeaker wiggle, a lot...
Loudspeaker – Makes air wiggle, a little or a lot...
Wiggling Air – Makes people wiggle. (Whole 'nother subject. Back to gain...)
For the simple sources above, we simply plug into an input channel of our favorite gizmo, hit it as hard as we're gonna and then adjust that channel's controls, step by step - first Trim, then Level - for the desired result, optimum performance. Repeat for each additional source. Then we bring up the Master volume control to the desired listening level. Now that we can hear the individual sources clearly, we can modify their tone with EQ, their mix (relative balance) with Level controls and the overall loudness of that mix with the Master, to suit our tastes and needs.