DAVE HILL DESIGNS Europa I Mono Preamplifier User Guide
- June 17, 2024
- DAVE HILL DESIGNS
Table of Contents
DAVE HILL DESIGNS Europa I Mono Preamplifier
Product Information
The Europa I Preamp is a high-quality signal-processing device designed for
professional audio applications. It features various controls that allow users
to adjust the color and distortion of audio signals. With a maximum input and
output level of +24dBu at
0dB gain, the Europa I can be used effectively in signal processing within a
mix.
Specifications
- Mic Impedance: HI-Z 2.2K OHMS, 300 OHMS PHANTOM POWER
- Gain: Mic Gain 0 to 66 dB, HI-Z Gain 0 to 30 dB
- Controls: Speed, Odd Harmonics, Power, Phase, Mic Instrument Select, Low Cut, Hi-Z Instrument Input, Even Harmonics
Product Usage Instructions
Adjusting the Color and Distortion
To change the colour and add distortion to your audio signal, follow these steps:
- Start with a clean unprocessed voice.
- Set the Speed control to 5.
- Slowly increase the level of the voice from peaking at +4 to the maximum level.
- Note how the colour and distortion change as the level increases.
- Experiment with different settings of the Speed control to find the most useful ones for vocals. A setting of 4 is often recommended but can be adjusted based on the desired effect.
Series Controls
Since the controls are in series, you can try the following steps for a drum or voice:
- Bring up both the Speed control and the Odd Harmonic control.
- Compare the processed audio with the unprocessed audio to observe the differences in colour and distortion.
Low Cut Filter
The Europa I Preamp also includes a Low Cut Filter: Set at 18 dB/octave, this filter can be used to reduce low-frequency noise or unwanted rumble in your audio signal.
(FAQ)
Frequently Asked Questions (FAQ)
- Q : What are the maximum input and output levels of the Europa I Preamp?
- A: The maximum input and output levels are +24dBu at 0dB gain.
- Q : How should I set the Speed control for vocals?
- A : It is recommended to start with a setting of 4 and adjust it based on the desired effect. Higher settings can add more distortion, while lower settings produce a cleaner sound.
- Q: What is the purpose of the Low Cut Filter?
- A : The Low Cut Filter is used to reduce low-frequency noise or unwanted rumble in audio signals. It has a slope of 18 dB/octave.
INTRODUCTION
This is the start of a manual; it is to provide some information on what to do
with the colour controls. At 0db gain the maximum input and output levels
are+24dbu, this allows the Europa 1 to be used for signal processing in a mix.
Controls that change the color or add distortion are always difficult to
describe The first control in the chain is the Speed control, the others
follow in series. 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. Low amplitude signals will pass unaffected, but large
signals that change fast will be slowed down. The easiest way to learn what
this does is to 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 setting to 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.
The 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 colour controls because the
second harmonic is the hardest to hear. As for how the Speed control works, it
is level-dependent and will affect the audio more as the signal increases from
0VU to the maximum level. 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 with how the other colour controls work, it is level-dependent and
will affect the audio more as the signal increases from 0VU to the maximum
level. Being the controls are in series, try the a drum and or voice and bring
up both the Speed control and the Odd Harmonic control. Compare this with the
unprocessed audio.
The level dependence is the same thing that happens with all vintage analog
gear. This is not about making a colour by adding a little LF boost or a
little HF cut; it is changed in amplifier linearity. The microphone input has
3 input impedance choices which are 2.2K ohms for normal microphone operation,
300 ohm and a Hi-z choice for different microphone sounds. The instrument
input has an impedance of 1.2 Meg ohms which is ideal for guitars. The gain
overall is adjustable in 1db steps from 0 to 66db on the mic input and 0 to 30
db on the instrument input. Gain is displayed on a 2-digit led display. The
low cut filter which is a 3 pole, 18db per octave has 8 frequencies 148 Hz,
130 Hz, 117 Hz, 100 Hz, 81 Hz, 63 Hz, 48 Hz, 33 Hz, and off.
One thing to note is on power-up, a number is displayed in the leftmost gain
digit. This is the firmware version number. 0VU on the meter is +4dbu, tha top
of the meter shows 20 db above +4. A maximum lever lof +24dbu clipping is
somewhere between +24 and +25 dbu on the output. The maximum input is +24
balanced and about +17dbu unbalanced.
USING INSTRUCTION
- The top wave shape is a vocal recording The bottom is the same slowed down by the Speed control; this is an extreme case to show the effect on the wave shape
- FREQUENCY RESPONCE OF WITH THE SPEED CONTROL SET TO 1 NOTE: LOW-LEVEL SIGNALS HAVE A NEAR FLAT RESPONSE HIGH LEVEL SIGNALS ARE CHANGED
- EVEN HARMONIC DISTORTION WITH LEVEL
- ODD HARMONIC DISTORTION WITH LEVEL
- LOW CUT FILTER