Operating Theatre: Peavey VTM 120

The Peavey VTM 120 is [looks around to see who is listening] a great fucking amp. Don’t tell your friends, because you can still get ’em relatively cheap. It’s essentially a JCM 800 clone with a set of DIP switches “to avoid any Imperial entanglements.” Sebastian Phillips, my bandmate in Exhumed, swears so much by his that he has one for each coast. He even got our other guitfiddler, Matt Harvey, to get one as a back-up for his 5150 (or 6505… I can’t keep track).

Of course, even a good amp has a bad day. This trooper made it through a marathon six-week tour, but upped and quit on us the very last day. It just stopped turning on. Luckily, Matt had that back-up, so Sebastian didn’t lose his groove. I took the amp after we unpacked our shit and did my doktor thing.

I had a very frustrating conversation the other day about a fade out on a song. I thought it sounded too fast. To me, it sounded very linear. I was trying to explain it should be a logarithmic fade out. Sarcastically, I was told I should teach a class on the subject if I flippin’ knew so much. So fuck it, class is in session. When speaking about audio, what does one mean when using the terms “linear” and “logarithmic?”

linear_v_logarithm — Nothing draws readers in like math!

For a linear fade out, a linear equation of the dB decrease could be shown simply as y=e*x+dB, where e is a negative number. That’s a straight line heading downward. When speaking about “logarithms” in audio applications, though, it’s actually describing several things: exponential and logarithmic curves, and their reverse functions. For a “logarithmic” fade out, the function would be y=e^x*dB, where e is a number between 0 and 1; that is an exponential function showing decay. For fade ups, the function can be reversed to y=e^x/dB to show an exponential increase in volume. Fucking confused, yet? YES!*

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