7900s O S C an Amplitude Modulator
version 1.0
In this text, all parameters (sliders) and attributes are colored red.
What is Amplitude Modulation ?
Straight forward, Amplitude Modulation means: Volume Variation.
A standard Amplitude Modulator has the following three features:
1. The variation speed can be controlled by asigning: the frequency (also called LFO frequency).
2. The variation can also be giving a certain shape,
the way the volume is changed (also LFO shape), the shapes are:
100% dry (no shape, but this turns the AM off),
saw, -saw, tri, pulse, sine.
3. Finally you can set the amount of which
the volume is modulated.
Amount = 100%
means the volume can change from 0 to 100 %
Amount = 60 % (for
example) means the volume can change from 40% to 100%
Amount = 0 % means
the volume keeps on 100% (same as 100% dry)
When the shape 'pulse' is chose, one so called period exists of
a part with 100% volume, and a part with (100 - amount) % volume.
When pulsewidth is set to bigger than 50%, then the part with
100% volume gets bigger and
when pulsewidth is set to less than 50%, then the part with
100% volume get smaller.
This part has 3 parameters (sliders).
It makes the main-frequency (mentioned above) go a bit slower and then back to the speed
it is set on
(just like when you're moving the main-frequency slider yourself), with the value of
main-frequency as the right-end.
1. With freq-of-freq you can alter the rate with which the
main-frequency is modulated / changed.
2. With fof shape you can set the way this change manifests
itself. Look at it as the way you would move the
main-frequency slider to the left and back, this is how the different
shapes behave:
none
turns off the modulation of the main-frequency
saw
will act as if the slider quickly jumps to the left and then is drawn to the right (at
constant speed).
-saw
just the opposite of saw
tri (triangle) will act as if
the slider is drawn to the left and back at a constant speed
pulse
will
let the main-frequency jump to the left and back
sine
same as tri but smoother
3. With fof amplitude you can set the influence that this
frequency-of-frequency (and shape) has on the main-frequency.
0 % means no influence, 100% means a lot influence.
Using these parameters with those mentioned in (4) will make the sound shitty, so it's not
recommended.
This part has 3 parameters (sliders): freq-of-amount,
foa shape and foa amplitude.
It makes the main-AM-amount (mentioned above) more, or makes it less.
It works the same way as the parameters in (3), but now it doesnt change the
main-frequency, but the main-AM-amount.
Using these parameters with those mentioned in (3) will make the sound shitty, so it's not
recommended.
stereo phase, phase difference between left
and right stereo channels.
Instead of doing the same with both stereo channel at the same time, it does the same but
now on a other time.
Because this effect does AM, a channel has: a period of loud sound, and a period of soft
sound.
When both channels are IN PHASE (at 0% or 100% of 2 PI) these periods are exactly on the
same time. When you shift the phase, these periods happen
at another time. Maximum phase-difference (at 50% of 2 PI) means that the channels
do the opposite.
divider [slow down] frequency : Can be set in the attribute dialog (right click on machine), ranges from 500 to 5000 (default = 2000). It sets the frequency range of all three LFO's. The higher the value, the slower the LFO can go.
This effect works with the soft-studio BUZZ www.jeskola.com , get other effects at www.BuzzMachines.com
You can send me some mail if you like at: jvdlubbe@kabelfoon.nl
.
or some of your music on cd:
Jochem vd. Lubbe
Flothuisstraat 8
2692 CM
's-Gravenzande
The Netherlands
Thanx and greetz:
MvA, Zephod, Thev, Hymax, Apo, SurfSmurf, ofcourse Oskari for making Buzz
and all others at EFnet's #buzz and #buzzdev