Engl Fireball 25 User manual

E633
Fireball 25
Operator´s Manual

Input
Input ¼“ (6.3mm) unbalanced input. Plug your guitar in here using a shielded cord.
Clean Gain
Gain control for the Clean channel.
Lead Gain
Gain control for the Lead channel.
Bass
Bottom end voicing control of the preamp´s passive EQ.
Middle
Mid-range voicing control of the preamp´s passive EQ.
Treble
Upper range voicing control of the preamp´s passive EQ.
Lead Volume
Volume control for the Lead channel (pre-FX Loop, inuences the send level). Use this knob to dial in the
desired balance of levels between the Lead and Clean channels.
Mid Boost
This voicing feature operates globally, affecting both channels by boosting specic midrange frequencies
when activated. The red LED above the button lights up to indicate Mid Boost is activated. It may also be
controlled remotely using a footswitch.
Once a footswitch is connected, the function of the Mid Boost push-button is deactivated.
Clean/Lead Channel
Selector push-button for Clean and Lead channel, red LED indicates Lead channel. This function can also
be activated via the respective footswitch connected. Once a footswitch is connected, the function of the
channel selector push-button is deactivated.
Master
Master volume knob, located post FX Loop. It controls the power amp output level.
Presence
This control denes the Treble response in the power amp stage.

Stand By
Power amp Stand By switch: Use this switch to silence (0 position) the amp when you take a longer break.
The amp‘s tubes stay nice and toasty, and the amp is ready to roll immediately when you ramp it back up to
full power. The Stand By switch is also well-suited for silencing the amp for brief breaks, for instance when
you‘re switching guitars.
Power
Mains power on/off.
Please note: ensure that the Stand By switch is set to Stand By (0 position) before you switch the amp on.
Let the tubes heat up for about 30 seconds before you activate the power amp. This procedure conserves
the tubes.

Main Supply Connector (AC Power Inlet, IEC – C14 connector)
Plug the mains cord in here.
CAUTION! Make sure you use an intact mains line cord with a grounded plug! Before you power the amp
up, ensure the voltage value (e.g. printed on the Type Label or alongside the mains port) is the same as the
current of the local power supply or wall outlet. Please also heed the guidelines set forth in the separately
included pamphlet, Instructions for the Prevention of Fire, Electrical Shock and Injury.
Mains Fuse Box
The rear chamber contains the mains fuse and the front chamber a spare fuse.
NOTE: Ensure replacement fuses bear identical ratings (refer to the technical data)!
CAUTION! Always make sure replacement fuses are of the same type and have the same ratings as the
original fuse! To this end, please refer to the fuse ratings shown on the type panel.
Footswitch
Mid Boost, FX Loop, (conventional 6.3mm / ¼“ TRS). Use this jack to connect a conventional footswitch with
two switching functions, i.e. the ENGL Z4 (2 x off/on – Single Pole Single Throw or SPST for short).
Tip: switching Mid Boost on and off.
Ring: switching the FX Loop on and off.
Default (no footswitch connected): Mid Boost is off, FX Loop is on.
Clean/Lead (conventional 6.3mm / ¼“ TRS). Use this jack to connect a conventional footswitch with two
switching functions, i.e. the ENGL Z4 (2 x off/on – Single Pole Single Throw or SPST for short).
Tip: switching between the Clean and the Lead channels.
Ring: switching Master Volume Boost on and off.
Default (no footswitch connected): Clean channel is activated, Master Volume Boost is off.
Noise Gate Threshold Level
This control activates the onboard Noise Gate serving to suppress any excess noise generated when the
Lead Channel is active. To this end, twist the knob clockwise, near or just beyond the 9 or 10 o‘clock position.
Use this knob to set a threshold value (that is, the noise level) at which the Noise Gate activates to suppress
the signal within the 9 to 5 o‘clock range. The further you twist the knob to the right, the higher the signal
level at which the Noise Gate kicks in. If you set the knob to the 5 o‘clock position, the Noise Gate reacts
to extremely high noise levels, meaning that there‘s not much of a margin between the guitar signal and
background noise.

FX Loop
In the signal path, the FX loop is located post preamp and before the power amp Master controls.
FX Loop Send
Connect the FX-Loop Send (output) to a signal processor‘s or an effect pedal´s input/return jack using the
shortest possible shielded cord equipped with 6.3mm (¼“) plugs.
FX Loop Return
Connect the FX-Loop Return (input) to a signal processor‘s or an effect pedal´s output/send jack using the
shortest possible shielded cord equipped with 6.3mm (¼“) plugs.
Line Output – 0 dB
The Line Output port taps the power amp‘s output to provide a line out signal congured at a level of about
0 dB. The frequency response is identical to the power amp output signal. In other words, its frequency
response is not compensated or corrected. You can feed this signal to another linear power amp. Another
option is to patch it through an outboard lter to emulate a speaker, or for example into the ENGL CA-
BLOADER (IR-Loader with an integrated microphone and power amp simulation), and feed this externally
processed signal to a recording device or PA system.
Cabinet options
1. One 8-16 Ohm cabinet connected to a 8-16 Ohm jack.
2. Two 16 Ohm cabinets connected to the 16 Ohm jacks.
Important Note
We cannot stress enough the importance of proper impedance matching when connecting one or more
cabinets to your amp. Impedance mismatching can damage the power amp!
Always check the connected cabinet‘s impedance to conrm it matches the amp‘s output impedance!
Power Range Selector
Use this switch to activate the Power Soak and select the desired power level.
Full Power (approx. 25 Watts)
Mid Power (approx. 5 Watts)
Low Power (approx. 1 Watt)
Speaker Off (zero Watts)
When activated, the Power Soak´s resistors convert some or all of the power amp´s output into heat. So,
make sure air can circulate freely around the back of the amp!

TECHNICAL DATA
Output power approx. 25 Watts
Input sensitivity
Input: from -20 dB to approx. 0 dB max.
FX Return from -20 dB to approx. 0 dB max.
Output level
FX Send from -20 dB to approx. 0 dB max.
Line Out approx. 0 dB / 1 kΩ at nominal power output
Power consumption approx. 100 Watts (115VA) max.
Fuses
220 / 230 / 240 supply voltage 1 AT L (T: slow-blow)
100 / 115 / 120 supply voltage 2 AT L (T: slow-blow)
Power Tube Fuses 2 x 0,16 AM (M: medium-blow)
Important: Replace these with fuses with the same type and rating only!
Tubes
V1 ENGL ECC83 First Quality (FQ)
V2 / V3 / V4 ENGL ECC83 Selected
V5 / V6 ENGL 6L6GC Hand-Matched Duet
Dimension 42cm x 23cm x 23cm
Weight approx. 10,7 kg

A FEW COMMENTS ON TUBE AMPLIFIERS
Be sure to read this section before powering the amp up!
This amp´s input is extremely sensitive due to its high gain factor. In combination with inherent micro-
phonics of tubes, at certain settings this can elicit powerful feedback from the speakers – even without a
guitar being connected!
This occurs primarily when Crunch and Lead channels (that is, all channels whose preamp is easily overdri-
ven) are activated and the following settings are dialed in:
• Gain and / or Lead Gain knob past the 12 o´clock position
• Treble knob past the 12 o´clock position
• Crunch / Lead Volume knob past the 12 o´clock position
• Presence knob past the 12 o´clock position
Avoid setting the aforementioned knobs to extreme positions (that is, combinations in which several of the-
se knobs are set past the 12 o´clock position). This type of conguration can cause considerable feedback
that could severely damage your hearing and destroy speakers.
If you set the Volume or Master knobs to higher volume levels, always make sure to back off amplication
levels to prevent feedback by turning the Lead channel Gain knobs down. The same applies to these chan-
nel´s Treble and Presence knob settings.
Before you power the amp up, take a moment to check out the control panel and make sure that these knobs
are not set to any conguration similar to the one described above!
A FEW WORDS ON BACKGROUND NOISE IN TUBE AMPLIFIERS
You may hear slight background noise right after you power a tube amp up or even while you are operating.
It manifests as intermittent hissing or sizzling, crackling, or popping noises. Caused by tubes, this type of
noise may even occur with brand new tubes.
The noise is particularly noticeable in high-gain Lead channels. This is because the Lead channel´s provide
a very high gain factor, amplifying noise along with the usable guitar signal.
It is not necessary to swap tubes if you encounter this kind of noise every now and then, though you may
consider replacing tubes if it becomes a constant companion.

TROUBLESHOOTING
The output volume uctuates or drops:
• Take all effect devices (in front of the preamp and FX Loop) out of the signal chain.
• Check all used cables.
• Check the used guitar or use another guitar.
• Use a patch or guitar cable to patch the FX Send with the FX Return jack.
• Try using an external and functional power amp with the preamp of the amp (FX Send connected to an
external power amp) to exclude a problem with the amp´s internal preamp.
• Try using an external and functional preamp with the power amp of the amp (FX Return connected to
an external preamp) to exclude a problem with the amp´s power amp.
The amp is not providing a proper output signal / no or low sound is emanating from the speaker:
• Is at least one speaker connected to the speaker outputs?
• Is the power amp activated (Stand By switch to ON)?
• Are all cords (guitar, effects and speaker) connected properly and are they functional?
• Take all effect devices (before the preamp, FX Loop) out of the signal chain.
• Is the Noise Gate activated? (Relevant only, if the amplier is equipped with a Noise Gate).
• Are the Master knob and the Gain and Volume knobs set to a value higher than 0? If any of these knobs
is set to zero, no signal is routed to the amp´s output.
The speaker is emitting humming noises:
• The amp and mains ground are not connected properly or are altogether disconnected. Please have
this checked by a technician.
• Chords connected to the input or FX Loop may not be shielded properly. Replace them to check if this
is indeed the case.
• The amp or speaker cords may be picking up interference from powerful magnetic elds (i.e., of
nearby power transformers or electrical motors). Reposition the amp and connector cables.
• The amp or speaker cords may be picking up radio signals. For example, from activated mobile phones
or powerful local transmitting stations nearby. Switch off mobile phones while troubleshooting noise
problems.

Please contact us via e-mail: [email protected] before shipping a product to us.
The more precise the error description is, the better our service team can help you. It is best to send us
a photo of the control settings and a video recording. A detailed description of the error also helps us to
isolate and locate the problem faster.
• Which channels are affected?
• Which functions are activated?
• In which knob positions does the problem occur?
• Are you using effects devices before the input or in the FX-Loop?
• Does the problem occur in standby mode (noise issues)?
• What equipment is used in detail?
Packaging
Please make sure to use suitable packaging to ensure undamaged transport (use original PKG). To unfold
the full protective function of the packaging, the outer packaging, the device and the inner packaging must
form a single unit. This is the only way to ensure that the device survives the transport route undamaged.
Please check used packaging for tears, signs of compression, pressure marks, perforations or other da-
mage before use. Please do not use damaged packaging. Note that a ight case is not a suitable shipping
packaging and is therefore not accepted. Please never pack devices together (e.g. Z4 Footswitch + E633
Head), but send them separately. As it is our responsibility to use suitable shipping packaging for re-
turn shipping, we reserve the right to use a new original packaging if necessary and must also invoice it.
Original Packaging
Our original packaging consists of particularly thick cardboard material and is equipped with special, cus-
tom-made molded foam parts for each model.
This packaging can be used several times - do not throw it away!
Tubes
When replacing the power amp tubes, the operating point (BIAS) must be set. If you use ENGL tubes with the
same “grade”, the operating point does not have to be set.
When replacing the preamp tubes, please be ensured that the input tube will be replaced with a specially
selected ENGL FQ (First Quality) ECC83 / 12AX7. The remaining preamp tubes should be replaced with ENGL
Selected ECC83 / 12AX7.
Whilst the information contained herein is correct at the time of publication, due to our policy of
constant improvement and development, ENGL AMPLIFICATION reserves the right to alter speci-
cations without prior notice.

NOTES

NOTES

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