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Bad Cat LIL'15 Operating Manual page 2

Professional tube amplifier

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Front & Rear Panel Controls
LIL'15
OPERATION
If this is your first all-tube amplifier, please become familiar
with a few issues that differentiate your amp from solid-
state or hybrid amp products. Only a few precautions are
required but they will insure that you will get the most of
your new all-tube amplifier. Vacuum tubes are "old world"
thermal devices that require more attention than transis-
tors, but that's the reason they sound so much sweeter and
more musical than integrated circuits and other solid-state
components. A little heads-up on the following points will
ensure maximum performance from your Bad Cat amp.
1. Place the amp at least 6 inches away from any wall or
obstacle to provide adequate ventilation around the amp.
Good airflow around the amp will go a long way in prevent-
ing the amp from overheating, especially the tubes. Do not
place covers, clothing, or any other materials on or in the
amp that can obstruct the free venting of the chassis to the
outside air. Trapped heat in the chassis may cause a condi-
tion known as thermal runaway. To put it simply, to warm
or cook the tubes is good, to heat-cycle or fry the tubes is
extremely dangerous and will also shorten the life of the
tubes considerably.
2. Vacuum tubes will last longer and sound more musical
when they are allowed to warm up prior to introducing an
input signal from your guitar. A full flow of electrons from
the cathode can only be achieved when the tube is heated.
This requires some time. Please allow at least one minute
of warm-up time before playing through the amp.
3. Avoid long idle periods with no input signal. The vacuum
tubes prefer to see a signal present. When taking a break
between practice sessions or in between sets of a perfor-
mance, use the standby switch or turn off the amp.
4. Avoid unverified impedance loads. In other words, do not
clip on or otherwise attach additional speakers unless you
know the system impedance. Tube amplifiers are very sen-
sitive to speaker impedance matching. This is due to the
relationship between the internal resistances of the output
transformer, the output power tubes and the load that is
required to drive them. Unbalanced loads can cause de-
structive arcing; the transformer and the tubes may actually
burn themselves out. This is not covered by our warranty.
With proper impedance matching, multiple speaker config-
urations will work fine. If you are not familiar with "Ohm's
Law", please consult with a dealer or a qualified amplifier
technician. Do not attempt to operate the amp if you can-
not verify system impedance after connecting the speakers.
Never operate your Bad Cat amp at 2 ohms or less.
5. Avoid unapproved "Power Soak" devices or attenuators
that are not recommended by Bad Cat as they can shorten
the life of your power tubes considerably. Attenuators burn
out tubes prematurely because they require the power
tubes to overwork continuously. Also, please note that pow-
er tubes are best replaced as a matched full set whenever
any of them fail.
LIL'15 FRONT PANEL
A/B
Volume
Gain
Input
Off Stdby On
FRONT PANEL
Input
Guitar cord
Volume
The first knob on the left when you face the amp's front panel is the volume
control for the clean channel. This is the input stage where the preamp tubes
first "see" the guitar signal and goes through the first phase of amplification.
Although designed as the clean channel, you can crank up the volume pot and
your picking attack to get varying degrees of clean and overdrive sounds.
A/B Switch
Manual toggle switch selector for Channel 1-2
Volume – Channel 1
The first knob on the left when you face the amp's front panel is the volume
control. This is the first input stage of the preamp.
Gain – Channel 2
The Gain knob controls the amount of gain applied. Set the knob low (approxi-
mately 9 o'clock to noon) and you will get bluesy breakup to classic rock crunch.
Turn the knob clockwise past noon and you get punchy hard rock distortion to
modern over-the-top metal and shred tones. You will also notice that the gain
is very sensitive to your guitar volume knob adjustments and your picking at-
tack. The touch sensitivity of the amp's gain control allows you to access a wide
range of overdrive and distorted sounds without having to readjust the Gain
knob in between noon and 2 o'clock and use your guitar volume knob to go from
bluesy with slight breakup to crunch to searing saturated leads.
Tone – Channel 2
This is a 5-position knob used for instant access to your favorite sounds. Turn it
clockwise for increasingly darker, thicker tones. Turning the knob counterclock-
wise gives you more treble and bite. The 5-position switch gives you a distinct
advantage in being able to recreate the tone you want time after time.
Cut – Channel 1-2
This knob works like a "Presence" control found on many tube amplifiers but
the control works opposite from traditional "Presence" controls. Turning the
knob clockwise will cut the highs, darkening the overall sound. Turning the
Bass
Treble
Master
AC Voltage
Foot
Line
Speaker
2 Amp
Switch
Out
120 Volt
knob counterclockwise will add more highs and high-mids, significantly bright-
ening the overall sound. It's a tone-shaping function on the amp that with careful
tweaking gives you a range of sounds from a single-channel amp unmatched
in this industry.
Master – Channel 2
The Master knob controls the overall output of the LiL 15' when using the gain
knob in channel 2.
BACK PANEL
Off, Standby, On
This switch turns the amp on, off or on standby. Leave the amp on to let the
amp warm up for a full minute before turning the Standby switch on. It's best
to let tubes warm up before playing. Also, turn the switch to Standby when you
will not be playing for a while (for example, breaks in between sets of your
performances, etc.).
A/C Plug
Plug your amp's power cord in here first, then to the wall.
Footswitch
This is the provided footswitch to change from channel 1 to channel 2.
Lineout
This is a line-level output which can be used directly into a processor or effect
unit, thereby making your amp the preamp or tone-shaper of a larger "rack" rig.
This can also be used for direct recording, although typically clean sounds work
best for this purpose as the distorted sounds tend to suffer from the lack of the
positive coloration a speaker brings to a distorted guitar tone.
Speaker
This jack is adding an extension speaker cabinet to be used with the internal
speaker. The internal speaker runs at 8 ohms for a single 12 or 4 ohms for a
2x12 and is parallel with the extension speaker jack.
Speaker Impedance
On a combo this rotary selector knob comes set at 8 ohms for a single 12 or
4 ohms for a 2x12. The selector knob can select between 4, 8 and 16 ohms.
Check Ohm's Law if using an additional extension cabinet to select the right
ohm setting. Example: 8 ohms + 8 ohms = 4 ohm setting.
On a head, please be sure to select the proper ohms to
match your cabinet.
TROUBLESHOOTING
Your new Bad Cat amplifier is designed for many years of
professional trouble free operation. Common sense will tell
you that if you notice any severe abnormalities in operation
like burning smell, smoke, etc.; you need to shut down the
amp immediately. Always consult your Bad Cat dealer if you
are unsure of the problems that you are dealing with; i.e.,
take your amp to where you purchased it.
No Power
Check the power source from the wall first. Make sure the
power cord is properly seated at both ends. If there is still
Impedance
no power, check the fuse and replace if necessary with the
correct rating.
16
8
Weak Output Level
Verify the signal output from your instrument first. Check
4
guitar's controls and that the cables are working properly.
Bad Cat U.S.A.
Also, check any effects pedals that may be connected in
between the guitar and the amplifier.
LIL'15 REAR PANEL
Adverse Sounds-Hum, Whistle, Loss of Dynamics,
Feedback, Howling
Check loudspeaker cones, frayed guitar cables, controls on
your instrument, the guitar's pickups and any other devices
that many be connected to your amplifier such as effects
pedals or rack processors. Some of these devices are "am-
plifiers" in their own right with gain and boosted volume
levels and they may cause hissing and unwanted feedback
if set too high in front of the amp. Shut down the amp and
check the tubes. Wait for the amp to cool down. Remove
the back panel of the amplifier. Avoid handling hot tubes
as they can cause severe burns. Check the larger output
power tubes first by carefully removing the tube shields,
and then unseat the tubes from their sockets but note from
which sockets you removed the tubes. Inspect the integ-
rity of the filaments in the tubes. If one or more of these
tubes are bad, you will need to replace the entire set of the
power tubes. If all the tubes are OK, you can eliminate the
adverse sounds by swapping the location of these tubes.
If this fails to fix the problem, you may need to replace the
entire set of power tubes with a new matched set. Use of
inferior quality (unrated) tubes may cause damage to your
amplifier. You should also check the preamp tubes, espe-
cially the first input stage tube (far right if you're looking at
the amp from the back). Microphonics (feedback noise that
cannot be controlled by turning down the volume pot on
you guitar) indicates a bad preamp tube(s). You may want to
swap the position of preamp tubes to see if this will fix the
microphonics problem. Preamp tubes can go bad without
warning but can also last many years without any problem
whatsoever. As you can see when handling tubes, they are
sensitive, fragile and somewhat prone to inconsistencies.
Please handle your amp with care when transporting it.
Although your Bad Cat amp is sturdily built and designed
to take years of rugged use, the tubes are not. It's always
a good idea to keep extra tubes (both preamp and output
power tubes) handy, especially for performance situations.
An overwhelming majority of minor problems on tube amps
are tube-related and it's just a matter of swapping one
or more out to have your amp performing like brand new
again.

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