Engl TUBE PREAMP 570, Руководство оператора

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telltale signs that feedback is swelling and consequently can't take measures to
suppress it. For this reason, make an extra effort to be careful when the is
activated: Before you approach the preamp or 19" racksystem and speaker cabinet
with your guitar in hand, turn the guitar's volume knob to the far left position (to 0 so
that no signal is audible) to prevent the pickups and speakers from interacting!
Noise is a definite no-no in many situations. For example, studio etiquette demands
that you keep a lid on extraneous noise during short breaks. It's in the nature of high-
gain rigs to generate undesirable peripheral noise in overdriven channels. This is
attributable to the physical properties of an amp's constituent components, in
particular its active components. That's right; those cherished tubes are the culprits.
The Noise Gate is a tool that lets you silence this noise during breaks by way of signal
mute circuit. Note that electric guitars pick up interference signals, and these are
amplified tremendously at high gain levels in Lead mode. The most common source of
noise is 50 or 60 hertz mains hum, particularly when the guitar is positioned near
transformers and power units. Because in worst-case scenarios this humming can
attain extremely high levels, the Noise Gate can hardly distinguish between the
musical signal and noise. This makes it hard to find the right Threshold setting. It is
entirely possible for this humming and other noise to rise to a level that deactivates the
and therefore becomes audible. My advice is to stay as far away from
transformers and power units as space allows.
Noise Gate
Noise Gate
A tip from the designer:
34 WRITE/COPY
Press this button to store the modified setting of a programmable feature to a MIDI
memory slot (generally called a preset). Here's how to distinguish between and
: with the former you're actually programming or writing a new MIDI preset, with
the latter you're making an exact duplicate of an existing preset.
The system will select a Write operation whenever you edit a MIDI preset, that is, when
you have modified a programmable feature. You'll know that this is the case because
the Status LED flashes steadily when you edit one or several programmable features. If
you press the button and did not edit a MIDI preset, the system will select . This
means that the given preset becomes the source, and its contents are dumped to
another preset and stored there.
The system quits mode autonomously
if you do not select a new MIDI preset within about 30 seconds.
The preset programming process -- the Write command, that is -- is not carried out as
soon as you press the button. Pressing the button merely initiates the process. You
must hold it down for about a second until the Status LED flashes three times in rapid
succession. This mechanism is designed to prevent inadvertent programming. You can
cancel the programming process at any time before the Status LED first illuminates by
releasing the Write button. Again, the preset will only be programmed successfully if
you press and hold the button until the Status LED flashes three times.
Write
Copy
Copy
Copy
When you press this button, the Status LED lights up
continuously to indicate is activated.
You'll have to go through a similar routine to copy a preset once you select a target
preset: When the Status LED extinguishes, the copy operation is underway and can no
longer be cancelled. The LED flashes three times to indicate the preset was copied
successfully. You can cancel the copy operation by releasing the key, but only for as
long as the LED lights up continuously.
Copy
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