User Manual

60
SPECTRALIS 2
Hybrid engine - The fixed filterbank
The first oscillator of this preset has been fed into the filterbank. The remaining
oscillators are not in use for this sound. Triggering notes from your midi-
keyboard will produce notes with a peculiar sound character as a result of the
filterbank spectral filtering.
Next push the [Level]-button in the filterbank section. This button assigns the
volumes of the individual filterbands to the encoders (1)-(10). Above the rotary
encoders (1)-(16) you can check the encoder-assignment corresponding to the
activated filterbank section. Adjusting the volume settings of the individual
filterbands 1-10 results in strong spectrum variations. Rolling back all levels
to 0 creates silence - no signal will pass the filterbank anymore. This behaviour
is the most significant difference compared to a normal graphic EQ.
The Spectralis allows feeding the filterbank signal either into the two analog-
filters or directly into the FX-processors or the output bus. For the preset
sound "VoiceSng" the filterbank signal has been fed into the multimode filter.
By turning the [CutOff MM]-encoder you can tweak the sound further. We
have kept the routing options as flexible as possible. Due to the fact that the
analog filters can be fed into the filterbank as well, it is possible to generate
feedback loops in the Spectralis sound engine. Used diligently you can create
totally off the wall special effects or of course kill your speakers if you overdo
it. To avoid the latter it is advisable to reduce the level of your monitor system
before starting any filterbank routing experiments.
Tip: In case you forgot about the above advice and all of a sudden – after
moving some parameters around - you are confronted with some
unexpected and annoying squeaking noises, chances are it is the result of
the multitude of routing options which as mentioned above can be used to
generate feedback. You already know a number of possible sources for
feedback - both of the analog-filters are resonating up to self-oscillation –
something also referred to “feedback”. It will be fairly easy to differentiate
this noise source from routing feedback , as the frequency of the
selfresonance oscillation will change according to the cutoff frequency.
The pitch of feedback caused by routing does not change when the cutoff
frequency is altered. It might get louder or softer, but that’s it. You should
have no problem differentiating the two sources of squeaking sounds.
When using the [Pan]-button in the filterbank-section, encoders 1-10 are
functioning as panpot-controls for the individual filterbands. You can set a
separate panorama position for each filterband, which allows the creation of
pseudostereo-effects.
We will now explore some additional parameters of the filterbank. First we
should select another soundsource with more spectral content than the basic
oscillator waveform, we used so far. An ideal source is white noise. Please
push the [Osc Wave]-button and then use the [Page-Up]-button to select menu
page 3/27. There you need to set the volume of the oscillator 1 to Zero. Now
select menu-page 24/27 “Noise Direct Volume”. You should see the following
display message: