Re: basic understanding of how electric guitar gear works

googledawg wrote:

AN ELECTRONIC PERSPECTIVE....

With a degree in Electronics Technology firmy in hand, i discovered
that i hated fixing things - it was a lot more fun to program
computers.....wish i'd known that first off....

however, i DID learn a ton of cool stuff -

STEP ONE:

let's assume that you are familiar with a "sine wave" - thats the kind
of wavy line produced by a jumprope or garden hose when you yank it up
in the air and back down - and ALSO the type of waves produced by audio
signals. and waves on the ocean, and lots of other physics
situations....

ok, so you can probably imagine a string of these sine waves on a
screen (this is the stuff of old science fiction movies) - supposedly
it was a death ray, and actually it was probably a low A note.....a
VERY PURE note to be sure, without a lot of complications.

OK - step TWO - the "wider" it is, the lower the note..(called
frequency) the "hgher" it is (from top to bottom) the LOUDER it
is.....that's called amplitude..

In other words, horizontal axis is time, vertical is voltage.


at SOME POINT, the amplitude gets cranked up high enough so that the
peak of this nicely rounded sine wave hits the ceiling, and starts to
flatten out......

Have you ever done this for real? Put a dummy load on an oscilloscope and feed an amp a pure signal from an audio generator? You get different results with different amps.

Solid state amps will often get hung up at full amplitude for a while, then CHOP OFF into a mix of a square and triangular shaped wave. Often with a SPIKE on the front of it. UGLY SOUNDING. Partially due to lots of negative feedback that is typically in SS design, partially due to the nature of the beast (sand -- silicon -- solid state devices). FET's do it better that typical NPN, PNP output transistors.

Tube amps will do it more smoothly, but you can force them into a similar waveform that I describe above. Less spikes, smoother forms, and most importantly, smoother transitions (so you can control the "on the edge" distortion).

OK, like a bunch of mountain tops, all the same
height and all sliced off at some point by a giant something....

STEP THREE: the further you crank it, the more the sine wave starts
to look like a SQUARE WAVE. the walls get straighter up (and down)
and the top gets wider.
the space between where the wave WAS NOT, and where it is NOW (the
"corners") form the frequencies (LOTS OF THEM) that are part of the
harmonic overtone series.....

hang in there......THOSE overtones combined with the volume
(amplitiude) is what is calle distortion (AND also produces "sustain")

Technical point. It gives the illusion or the effect of sustain. Real sustain is in the instrument.


- SO - all those harmonics (NOISE) are part of the distorion and
sustain that can be achieved by simply cranking stuff.

on most amps today, that have "distortion" or "satutation" or what ever
- a PREAMP drives the signal to a square wave (and limited Volume) -
and then passes THAT signal to the POWER amp with which you can break
windows or whatever.

True, but GOOD master volume tube amps do EITHER or both. It's not just a matter of only having a preamp type distortion. You can also run CLEAN preamp and rely on output tube distortion, or you can get a nice mix.

NICELY ENOUGH, though, you can get all that
sustain and varying degress of distortion at low volume levels, since
it's there in the Preamp, BEFORE you crank it.....

the familiar "screeching" harmonics that we hear in the metal music
(about 3 octaves above your guitar range) are more easily attained with
the right settings,,,and the right picking technique.

In other words, excessive gain with lots of dynamics.


find the sound you want - get down to Bargain Bobs Band Box Music Store
and tell them what you want - they'll find it - maybe.....

do NOT ---REPEAT - do NOT --- go spend $1000 on equipment that "does it
all" when all might really want is a $29 distortion box (well, i gues
i'm showing my age- maybe like $69).......

the DAWG...

But you're missing one thing. SS and tubes behave DIFFERENTLY. You will not get the same control and touch response from a little SS stompbox. I've done this. I've looked that the waveform of Ibanez TS808, vintage Maestro Fuzz... next to the waveform of distorted tubes.

They sound different because they ARE different.
.

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