Dave Hill Designs EUROPA I, User Manual, Page: 5 / 13

A GUIDED TOUR
a self guided sound test
Controls that change the color or add distortion are always difficult to describe
The Speed control is a control that changes the way the preamp responds to transits. It is a control
that changes the slew rate, it is a rate of change filter. The fast position removes it from the audio
path. This is the default setting.
Low amplitude signals will pass unaffected, but large signals that quickly will be slowed down. The
easiest way to learn what this does is to do an experiment. Apply a snare drum to the preamp; adjust
the level so the peak is at +10 on the meter. Then move the Speed control from fast to a setting of 1
and then to 0. Compare this to the sound with the Speed control set to fast. Now go back and do the
same speed settings but increase the level of the drum until the drum peaks at max level. Note how
the sound changes as the level increases. Rate of change –
how much level and how fast .
Now switch to a clean unprocessed voice. Set the Speed control to 5 and slowly increase the level of
the voice from peaking at +4 to max level. Note how it changes as the level increases. I have found
that the settings of 4 to fast to be most useful with vocals. It depends on the level so it can be played
with. Level is one half of the rate of change function.
The Even harmonic control generates mostly second harmonic, but other harmonics as well. It is the
most subtle of the color controls because the second harmonic is the hardest to hear. This control is
also level dependent and will affect the audio more as the signal increases from 0VU to the maximum
level of +20 VU. Try a clean unprocessed acoustic guitar, if you set the control to 8, the maximum
control setting, and increase the level of the instrument, you should hear a change that I would
describe as thickening.
The control for Odd harmonics does two related things. First it adds odd harmonics, but it also
compresses. The odd harmonics and the compression are related. It brings up the low level part of
the signal and brings down the peaks.
Try a clean unprocessed voice if you set the control to 8, the maximum control setting and increase
the level of the voice, you should hear, more detail, and a brighter sound. But compared to the
unprocessed voice, there is a dynamic and transit change. The low level material will be louder, the
peaks will be less. As how the other color controls work, the odd harmonic control is level dependent
and will affect the audio more as the signal increases from 0VU to maximum level.