Olsson BJF100 User manual

BJF100 HEAD
OWNER’S MANUAL 1.0

WARNING! IMPORTANT SAFETY INSTRUCTIONS
Please read this manual carefully before
plugging in. Follow all instructions and heed
all warnings. Please keep this instruction
manual for future reference and for the
duration of owning this Olsson amplier.
What’s the meaning of this?
The lightning ash with an arrow triangu-
lar symbol is intended to alert the user to
the presence of non-insulated “dangerous
voltage” within the products enclosure, and
may be of sufcient magnitude to constitute
a risk of electric shock.
What’s the meaning of this?
The exclamation point triangular symbol is
intended to alert the user to the presence of
important operating and maintenanc instruc-
tions in the accompanying literature.
• All the safety and operating instructions
should be read before this product is
operated.
• Keep these instructions.
• Follow all warnings and instructions
marked on the product and in this man-
ual.
• Do not use this product near water. Do
not place the product near water, bathtub,
wash basins, kitchen sinks, laundry tub,
wet areas, swimming pools or damp
rooms, and the like.
• Do not place objects containing liquid on
the product – vases, glasses, bottles etc.
• This product should be located away from
heat sources such as radiators, heat
registers, stoves, other ampliers or other
products that produce heat.
• Unplug the power supply cord before
cleaning the unit exterior (use a damp
cloth only). Wait until the unit is complete-
ly dry before reconnecting to power.
• This product should be operated only from
the type of power source indicated on the
rating label. If you are not sure of the type
of power available, consult your product
dealer or local power company.
• Only connect the power supply cord to an
earth grounded AC receptacle in accord-
ance with the voltage and frequency
ratings listed on the rear panel of this
product.
• To reduce the risk of electrical shock,
the grounding of this product must be
maintained. In some countries it may be
equipped with a polarized alternation-cur-
rent line plug (a plug having one blade
wider than the other). This plug will t into
the power outlet only one way. Do not de-
feat the safety purpose of the polarized or
grounding-type plug. If the provided plug
does not t into your outlet, consult an
electrician for replacement of the obsolete
outlet.
• Protect the power cord from being walked
on or pinched by items placed upon or
against them, paying particular attention
to the cord in correspondence of plugs,
convenience receptacles, and the point
where they exit from the amplier.
• Never use a damaged power cord.
• Unplug this product when left unused for
long periods of time or during lightning
storms. This will prevent damage to the
product due to lightning and power line
surges.
• Care should be taken so that objects do
not fall and liquids are not spilled into the

enclosure through openings.
• This apparatus is for moderate climates
areas use, not suitable for use in tropical
climates countries.
• Do not block any ventilation openings.
• Refer all servicing to qualied service per-
sonnel. Servicing is required when the unit
has been damaged in any way, such as:
- When the power-supply cord or the plug
has been damaged.
- If liquid has been spilled or objects have
fallen into the product.
- If the amplier has been dropped, or the
enclosure damaged.
- If the amplier has been exposed to rain.
- If the amplier does not appear to oper-
ate normally.
- If the amplier exhibits a marked change
in performance.
- If the amplier needs tube replacement
or biasing.
• Always allow a cold device to warm up to
ambient temperature, when being moved
into a room. Condensation can form inside
it and damage the product, when being
used without warming up.
• Do not place this product on an unstable
cart, stand, tripod, bracket, or table. The
product may fall, causing serious injury to
a child or adult, and serious damage to
the product. Use only with a cart, stand,
tripod, bracket, or table recommended
by the manufacturer, or sold with the
product.
• Use only accessories recommended by
the manufacturer.
• Vacuum tube ampliers generate heat.
Maintain at least 20 cm/8” of unobstruct-
ed air space behind the unit and at least
50 cm / 20” immediately above it for
proper ventilation and cooling of the unit.
Keep away from curtains or any ammable
objects.
• This product is capable of producing very
high sound pressure levels which may
cause temporary or permanent hearing
damage. Use care when setting and ad-
justing volume levels during use.
• Do not place naked ame sources, such
as lighted candles on the product.
• Never operate the amplier without a
connected speaker or load since this can
cause severe damage to the amplier.
• The user should not attempt any service to
the amplier beyond that described in the
owners manual. All other servicing should
be referred to qualied service personnel.
• Make sure to use the correct rating and
type of fuse as indicated on the rear
panel.

INTRODUCTION
Congratulation on purchasing this new amplier, designed by the well known amp and pedal
designer Björn Juhl (BJF) in cooperation with John Olsson at Olsson Amplication in
Sweden. It’s an unique collaboration and this amp has it’s own sound and possibilities.
The BJF100 is a 100W EL34 powered two channel amp capable of producing many styles
of music. Both channels can produce distorted sounds where number one can go from
seemingly clean to fairly heavy distorted enough to play heavy music; and number two can go
from about clean sounds to break up (crunch). The idea is that most guitarist, when running
a clean sound, usually don’t want it to be clinically clean but wants some shimmer and
some limiting on the transients, so the second channels can set this gradually. Typically this
is a function produced in the power amp section but here we have successfully moved that
function into the preamp instead. Believe it or not but this 100W amp will sound great also
at bedroom volumes. Just turn the volume controls down and the sound will stay the same.
Also note that the clean and the overdrive channel has no components in common, resulting
in two optimized channels which is not very common in this type of amp.
Both channels comes with an effective three band EQ and Presence control.
Due to the unique pre-amp design the BJF100 takes pedals extremely well and the transpar-
ent FX-LOOP takes care of your time based pedals exceptionally.
The BJF100 amps are hand built by skilled engineers in Sweden and crafted with the nest
material for awless performance.
We hope that you will love this amp and if you have any questions don’t hesitate to contact
us at [e-mail].
Thank you for choosing an amplier from Olsson Amplication.

TECHNICAL SPECIFICATIONS
Model:
Mains:
Mains voltage tolerance:
Max power consumption:
Ambient operating temperature:
BJF100
Available in 100, 120, 220 or 230/240V versions,
50/60Hz
+/-10%
375W
0°-35°C
Main fuse 120V: 250V / T4A
Main fuse 220V: 250V / T2A
Main fuse 230/240V: 250V / T2A
HT fuse: 250V / T630mA
Heater fuse power amp: 250V / T8A
Heater fuse pre amp: 250V / T4A
Control voltage fuse: 250V / T500mA
Max output power: 100W in 4, 8 or 16Ω
Input impedance: 1MΩ
FX loop: Serial with send and return-level
adjustments.
Power tubes: 4 - EL34
Power amp: Fixed biased. Needs BIAS adjustment when
changing power tubes.
Pre amplier tubes: 4 - 12AX7
Dimensions: 640 x 280 x 210 cm,
Weight: 22kg/lbs.

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FUNCTIONS - FRONT PANEL
1. INPUT
Input jack for your guitar. Use a good quality
screened guitar cable.
2. GAIN
This adds gain/distortion to your sound. At
higher settings the compression and the
amount of overtones will increase.
3. VOLUME
This is the volume for the overdrive channel.
4. BASS
This controls the amount of bass or bottom
end.
5. MIDDLE
This controls the midrange. At lower settings
you will have a scooped sound and at higher
settings the guitar will be more easily heard
in the mix.
6. TREBLE
This controls the higher frequencies.
7. CHANNEL SWITCH
Switches between 1-Overdive and 2-Clean/
Crunch channel when foot-switch is not
connected. When using the foot-switch this
should be set to 2.
8. GAIN
This adds gain/distortion to your sound. At
higher settings the compression and the
amount of overtones will increase.
9. VOLUME
This is the volume for the clean/crunch
channel. If you like to make it a bit easier to
adjust the volume at very low levels, activate
the FX-Loop, without anything connected,
and decrease the send and return volumes
to desired levels.
10. CLEAN/CRUNCH
Switches between clean and crunch sounds.
The sound level increases a bit when setting
to Crunch.
11. BASS
This controls the amount of bass or bottom
end.
12. MIDDLE
This controls the midrange. At lower settings
you will have a scooped sound and at higher
settings the guitar will be more easily heard
in the mix.
13. TREBLE
This controls the higher frequencies.

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14. PRESENCE 1 AND PRESENCE 2
Adjusts the highs and upper mids in the
power amp section. This amp has separate
presence controls for each channel.
15. MUTE
When the switch is in mute position the amp
will be quiet and you can change the guitar
without any disturbing noise or hum.
16. POWER
Mains power on/off switch. Make sure that
there is a speaker load connected to the
amp before turning on.
17. POWER INDICATOR LAMP
Shows that the amp is turned on.
18. LED INDICATOR CHANNEL 2
When Channel 2 (clean/crunch) is selected,
this LED has two states. GREEN indicates
clean mode and ORANGE crunch mode.
19. LED INDICATOR CHANNEL 1
When this LED is RED, channel 1 (overdrive)
is selected.
NOTES:

FUNCTIONS - REAR PANEL
26272829
20. MAINS INPUT
Connects the amp to the mains electricity
supply. Use the supplied IEC power cord.
The MAINS INPUT socket has an integrated
fuse compartment. Ensure that the value of
a replacement fuse matches the labelling on
the amplier rear panel. You MUST ALWAYS
switch the amplier OFF and disconnect
it from the mains electricity supply before
attempting to access the fuse. If in doubt,
contact your dealer.
21-25 SERIAL FX LOOP
BJF100 is equipped with a serial FX loop.
If you activate the FX loop without anything
connected to SEND and RETURN you can
use it to control the overall output volume.
This is very useful if you like to play at bed-
room volumes and like to use higher settings
on the Volume control.
It can also be used as a volume boost. Just
activate the loop and adjust the send and
return level as you desire. By changing be-
tween bypass and active you can now switch
between the two levels.
21. SEND LEVEL
Controls the send level to external devices.
Start setting it to 3 o’clock. If the connect-
ed effect starts to distort more than usual
decrease the send level.
22. SEND JACK
Connect your external FX gear input to the
SEND jack.
23. FX LOOP SWITCH
Turns the FX loop on an off. When off the
loop is completely bypassed. To be able to
control the FX loop with the Foot Switch it
must be in active position,
24. RETURN JACK
Connect the external FX gear output to the
RETURN jack.
25. RETURN LEVEL
When the FX loop is active this controls the
overall volume of the amp. Set to 10 o’clock
to start with.
26. FOOT SWITCH FX LOOP
Connect a standard foot-switch to this jack
if you like to switch the FX loop on and off
remotely. To make the foot-switch active you
must rst activate switch No. 23 on the rear
panel.
27. FOOT SWITCH
Connect a standard double foot-switch to
this jack. One switch will be used for chan-
nel switching and the other for switching
between crunch and clean. To activate the

202122232425
foot-switch you must set the Clean/Crunch
switch to Crunch and the Channel switch to
2.
28. LOUDSPEAKERS
There are two parallel connected speaker
outputs available on the rear panel.
Connect the speaker(s) to the jack(s) and
set the IMPEDANCE SWITCH as follows:
1x16 ohm
Set the IMPEDANCE SWITCH to 16 ohm
1x8 ohm / 2x16 ohm
Set the IMPEDANCE SWITCH to 8 ohm
1x4 ohm / 2x8 ohm
Set the IMPEDANCE SWITCH to 4 ohm
Warning: Never use the amp without any
speaker load.
29. SPEAKER IMPEDANCE SWITCH
Set it to match the connected loudspeak-
er(s) as described in paragraph #28.
NOTES:

NOTES:

NOTES:

Olsson Amplication, Terrängvägen 17
129 48 Hägersten, Sweden
www.olssonamps.com