Tube Drive/Gain Reduction Display; Preamp Output - Art Pro Channel User Manual

Tube Drive/Gain Reduction Display

The top LED display (under the VU meter) shows how the tube gain is affecting the
input signal. These LEDs are calibrated with the tube circuitry to give you an accurate
representation of the tube's output signal
Note: These LEDs measure the signal level before the Preamp Output level control).
Use these LEDs as a visual guide for setting the Gain level. The first four (green) LEDs
are labeled "Cln." The tube is producing a clean output when these are lit. The next
four (yellow) LEDs are labeled "Warm." This is the optimal operating range for the Pro
Channel's preamp. At this level, the tube is producing an output signal that most would
term "warm" (Whatever you would like to call it is fine – simmering, toasty, etc.)
You'll find the output signal has an enhanced bottom to low mid quality with smooth
high frequency detail. The last two (red) LEDs are labeled "Clip." The first red LED
will light approximately 6dB before audible distortion occurs. If this light flickers,
don't panic. The unique design of the Pro Channel allows the tube to distort well before
any other gain stage. When a tube goes into distortion, it is a gradual process and tends
to sound pleasing for a range before it turns into a distortion box. After some use you'll
find that the "sweet spot" of the Pro Channel is when this light flashes fairly regularly,
and the top red LED flashes occasionally. You may very well find a "clipped" level is
suitable for some applications. Note: Use the Tube Character Array to aid in setting the
Gain Control.

Preamp Output

The Preamp Output control sets the output level of the preamp section of the Pro
Channel. In most situations you'll be leaving this control set around 12 o'clock (or its
"0" setting). The Preamp Output control has a range of no output (from its fully
counter-clockwise position), to +10dB of gain (when turned fully clockwise).
When setting up the preamp circuit, start with the Preamp Output at its "0" position.
Once you get the Gain control set the way you want it to sound, use the Preamp Output
control to set the level out of the preamp circuit (much like using the master volume
control on a guitar amplifier). Use the Preamp Output control to add more gain when
you have the Gain control set low for a "clean" sound. Likewise, you can use the
Preamp Output control to decrease the level out of the preamp circuit when you're
cranking the Gain control up for maximum tube warmth. Don't be afraid to set the
Preamp Output control very high if you desire a very clean signal, but with a good deal
of compression. (See Compressor Section.)
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