Acoustic GT50H User manual

GT50H
OWNER’S MANUAL
www.acousticamplification.com
50 WATT TUBE GUITAR AMPLIFIER

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IMPORTANT SAFETY INSTRUCTIONS
1. Read all safety and operating instructions before using this product.
2. All safety and operating instructions should be kept for future reference.
3. Read and understand all warnings listed on the operating instructions.
4. Follow all operating instructions to operate this product.
5. This product should not be used near water, i.e., bathtub, sink, swimming pool, wet basement, etc.
6. Only use dry cloth to clean this product.
7. Do not block any ventilation openings, it should not be placed flat against a wall or placed in a built-in enclosure that will
impede the flow of cooling air.
8. Do not install this product near any heat sources such as radiators, heat registers, stoves or other apparatus (including amplifiers)
that produce heat.
9. Do not defeat the safety purpose of the polarized or grounding-type plug. A polarized plug has two blades with one wider than
the other. A grounding-type plug has two blades and a third grounding prong. The wide blade or the third prong are provided
for your safety. If the provided plug does not fit into your outlet, consult an electrician for replacement of the obsolete outlet.
10. Protect the power cord from being walked on or pinched, particularly at plugs, convenience receptacles, and the point where
they exit from the apparatus. Do not break the ground pin of the power supply cord.
11. Only use attachments specified by the manufacturer.
12. Use only with the cart, stand, tripod, bracket, or table specified by the manufacturer or sold with the apparatus.
When a cart is used, exercise caution when moving.
13. Unplug this apparatus during lightning storms or when unused for a long period of time.
14. Care should be taken so that objects do not fall and liquids are not spilled into the unit
through the ventilation ports or any other openings.
15. Refer all servicing to qualified service personnel. Servicing is required when the apparatus
has been damaged in any way.
16. When a mains plug is used as the disconnect device, the disconnect device shall remain
readily operable.
Exposure to high noise levels may cause permanent hearing loss.
Individuals vary considerably to noise-induced hearing loss but nearly
everyone will lose some hearing if exposed to sufficiently intense noise
over time.
According to OSHA, any exposure in the above permissible
limits could result in some hearing loss. Hearing protection
must be worn when operating this amplification system in
order to prevent permanent hearing loss.
DURATION PER DAY (HOURS) 8 6 4 3 2 1
SOUND LEVEL (dB) 90 93 95 97 100 103
The U.S. Government’s Occupational Safety and Health Administration
(OSHA) has specified the following permissible noise level exposures:
This symbol is intended to alert the user to the presence of non-insulated “dangerous voltage” within the product’s enclosure.
This symbol is intended to alert the user to the presence of important operating and maintenance (servicing) instructions in
the literature accompanying the unit.
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Apparatus shall not be exposed to dripping or splashing. Objects filled with liquids, such as vases, shall not be placed on
the apparatus.
• The apparatus shall not be exposed to dripping or splashing. Objects filled with liquids, such as vases, shall not be placed on
the apparatus.
L’appareil ne doit pas etre exposé aux écoulements ou aux éclaboussures et aucun objet ne contenant de liquide, tel qu’un vase, ne
doit etre placé sur l’objet.
• Themainplugisusedasdisconnectdevice.ThemainplugofapparatusshouldnotbeobstructedORshouldbeeasilyaccessedduring
intended use. To be completely disconnected from the power input, the main plug of apparatus shall be disconnected from the mains.
La prise du secteur est utilisé pour déconnecter le systeme. La prise du secteur ne doit pas etre obstruée ou doit etre facilement acces-
sible pendant son utilisation. Pour etre completement déconnecté de l’alimentation d’entrée, la prise doit etre débranchée du secteur.
• Anappliancewithaprotectiveearthterminalshouldbeconnectedtoamainsoutletwithaprotectiveearthconnection.
Un appareil avec la borne de terre de protection doit etre connecté au secteur avec la connexion de terre de protection.
• WARNING:Toreducetheriskofreorelectricshock,donotexposethisapparatustorainormoisture.
Avertissement: pour réduire le risque d’incendie ou de choc électrique, ne pas exposer cet appareil sous la pluie et l’humidité.
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www.acousticamplification.com 2
GT50H
OWNER’S MANUAL
Acoustic P.O. Box 5111 Thousand Oaks, CA 91359-5111
All trademarks and registered trademarks mentioned herein are recognized as the property of their respective holders.
1109-9659
Congratulations on your purchase of a new Acoustic®
electric guitar tube amplifier. Founded as the Acoustic
Control Corporation in Van Nuys, California in 1967,
Acoustic®is the rig of choice for many legendary
touring musicians. If you’re new to Acoustic®amps, we
encourage you to get in tune with its rich heritage at
www.acousticamplification.com/history.cfm.
Your comments are important. We constantly improve our
products based on feedback from musicians like you. Please
feel free to contact us at www.acousticamplification.com
or send us an email at info@acousticamplification.com.
Welcome to Acoustic®, the Pro’s Tone Since 1967.
WELCOME
SPECIFICATIONS
Three Year Limited Warranty: Subject to the limitations set forth
below, Acoustic®hereby represents and warrants that the components
of this product shall be free from defects in workmanship and
materials, including implied warranties of merchantability or fitness for a
particular purpose, subject to normal use and service, for three (3) years to
the original owner from the date of purchase.
Thirty (30) Day Limited Warranty (Tubes): Subject to the limitations set
forth below, Acoustic®hereby represents and warrants that any tube
components of this product shall be free from defects in materials and
workmanship, including implied warranties of merchantability or fitness
for a particular purpose, subject to normal use and service, for thirty (30)
days to the original owner from the date of purchase.
For information on warranty replacement tubes please visit http://acoustic.
custhelp.com/app/ask/
Retailer and manufacturer shall not be liable for damages based
upon inconvenience, loss of use of product, loss of time, interrupted
operation or commercial loss or any other incidental or consequential
damages including but not limited to lost profits, downtime, goodwill,
damage to or replacement of equipment and property, and any costs of
recovering, reprogramming, or reproducing any program or data stored
in equipment that is used with Acoustic®products. This guarantee gives
you specific legal rights. You may have other legal rights which vary from
state to state. Some states do not allow limitations on how long an implied
warranty lasts, so the above limitation may not apply to you.
3
CAUTION!
Replace fuses with IEC type
127 (5x20 mm) and specified rating only!
Model GT50H
Power 50 Watts Maximum into 4, 8, or 16 ohms
Equalizer 3 Band + Bright switch and Presence control
Channels 2 + High/Low Gain switch and Boost Control
Effects Accutronics™ Spring Reverb + Effects Loop
Preamp Tubes 2 x ECC83S & 2 x 12AX7WB
Power Tubes 2 x 5881/6L6WGC
Mains Fuse 250V/T 3.15A (slo-blo)
Anode Fuse 250V/T 500mA (slo-blo)
Heater Fuse 250V/T 5A (slo-blo)
Dimensions H 10.83“ x D 10.69” x W 29”
Weight 35.61 lbs.

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POWERSTANDBY
25W PENTODE
12W TRIODE
MASTERREVERB
CLEAN
PRESENCE
LEAD
VOLUME
INPUT CLEAN
VOLUME
NORMAL
HIGH
GAIN
LOW
GAIN
GAIN
GT50H
BASS MID TREBLE
Tube Lead
Series
LEAD
50W PENTODE
25W TRIODE
AC IN FUSE FOOT
SWITCH
CHANNEL
HIGH/LOW GAIN
REVERB
BOOST
SEND RETURN
FX LOOP MIX SPEAKERS
16 0HM
DESIGNED IN CALIFORNIA MADE IN CHINA
Acoustic Amplification
P.O. Box 5111
Thousand Oaks, CA 91359-5111
www.acousticamplification.com
?????????
BOOST
LEVEL
DRY WET
MODE
TRIODE / PENTODE
TRIODE
25W
12W
PENTODE
50W
25W
4 0HM
OR
8 0HM 8 0HM&
8 0HM
OR
16 0HM 16 0HM&
GT50H
HEATER
250V/T 5A
ANODE
250V/T 500mA
CAUTION:
ENSURE THE DEVICE IS DISCONNECTED
FROM THE MAINS BEFORE REPLACING
THE FUSE. ONLY USE FUSES OF THE
SAME TYPE AND RATING.
~120V AC 50/60Hz 150W
T3.15AL/250V FUSE
BRIGHT
3
1. GUITAR INPUT: 1/4” two-conductor jack.
2. CLEAN VOLUME: Adjusts the relative volume of the
clean channel.
3. BRIGHT/NORMAL SWITCH: Enhances the high
frequencies on both the Clear and Lead channels when
switched to the “Bright” position.
4. HIGH GAIN/LOW GAIN:This switch increases the
preamp gain level on both the Clean and Lead channels
when switched to the “High Gain” position.
5. GAIN: This control increases or decreases the gain level
on the Lead channel.
6. BASS: This control increases or decreases bass
frequencies for both channels.
7. MID: This control increases or decreases mid range
frequencies for both channels.
8. TREBLE:This control increases or decreases treble
frequencies for both channels.
9. LEAD VOLUME: This control adjusts the relative volume
of the Lead channel.
10. PRESENCE: This control adjusts the upper high
frequencies when the Lead Channel is selected.
11. LEAD/CLEAN: Switches between the Lead and
Clean Channels.
12. REVERB: This control adjusts the level of the spring
reverb effect.
13. MASTER: This control adjusts the overall volume of
the amplifier.
14. HALF POWER SWITCH: This switch reduces the power
transformer output level to half power without
changing the sound of the amplifier. Switch between
50 watts and 25 watts when in Pentode mode. Switch
between 25 watts and 12.5 watts when in Triode mode.
CAUTION: The amplifier should be switched to
“STANDBY” before changing the transformer power
switch setting.
15. STANDBY: The Standby switch is used in conjunction
with the Power switch on tube amplifiers. The Standby
switch should be left in the off position for 2-3 minutes
after turning the Power switch on. This allows the
tubes to come up to operating temperature and will
extend the life of the tubes. The Standby switch should
be turned to the off position before turning the Power
switch off. The Standby switch can be used to turn off
sound from the amplifier while keeping the tubes at
operating temperature. Finally, the Standby switch
should be turned to the off position when changing
the position of the Half Power switch or the Triode/
Pentode switch in order to protect the amplifier and
extend the life of the tubes.
16. POWER: Turns the power on and off.
GT50H FRONT PANEL
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GT50H USER’S MANUAL
LEAD SERIES GUITAR AMPS
POWERSTANDBY
25W PENTODE
12W TRIODE
MASTERREVERB
CLEAN
PRESENCE
LEAD
VOLUME
INPUT CLEAN
VOLUME
NORMAL
HIGH
GAIN
LOW
GAIN
GAIN
GT50H
BASS MID TREBLE
Tube Lead
Series
LEAD
50W PENTODE
25W TRIODE
AC IN FUSE FOOT
SWITCH
CHANNEL
HIGH/LOW GAIN
REVERB
BOOST
SEND RETURN
FX LOOP MIX SPEAKERS
16 0HM
DESIGNED IN CALIFORNIA MADE IN CHINA
Acoustic Amplification
P.O. Box 5111
Thousand Oaks, CA 91359-5111
www.acousticamplification.com
?????????
BOOST
LEVEL
DRY WET
MODE
TRIODE / PENTODE
TRIODE
25W
12W
PENTODE
50W
25W
4 0HM
OR
8 0HM 8 0HM&
8 0HM
OR
16 0HM 16 0HM&
GT50H
HEATER
250V/T 5A
ANODE
250V/T 500mA
CAUTION:
ENSURE THE DEVICE IS DISCONNECTED
FROM THE MAINS BEFORE REPLACING
THE FUSE. ONLY USE FUSES OF THE
SAME TYPE AND RATING.
~120V AC 50/60Hz 150W
T3.15AL/250V FUSE
BRIGHT
4
GT50H REAR PANEL
1. AC INPUT: Attach the included AC power cable here.
2. MAINS FUSE: Contains the fuse for the amplifier mains.
Replace with the same type and value only.
3. HEATER FUSE: Contains the heater fuse for the preamp
and power amp tubes. Replace with the same type and
value only.
4. ANODE FUSE: Contains the anode fuse for the power
tubes. Replace with the same type and value only.
5. TRIODE/PENTODE SWITCH: Use this switch to select
Triode or Pentode mode for the tubes. CAUTION: The
amplifier should be switched to “STANDBY” before
changing the Triode/Pentode setting.
6. BOOST LEVEL: This adjust the level of the Boost
Function when engaged. This acts as a Lead
Boost of up to 15dB. This function can only be
accessed and turned on with the included GFS4
footswitch attached.
7. FOOTSWITCH JACKS: Connection for the GFS4, 4
button footswitch (included) via a 2 stereo 1/4” cables
(included). Switches Clean/Lead channel, High/Low
Gain, Reverb On/Off & Boost On/Off.
8. EFFECTS LOOP SEND: Accepts 1/4” instrument
connectors.
9. EFFECTS LOOP RETURN: Accepts 1/4” instrument
connector.
10. EFFECTS LOOP MIX CONTROL: Blends the parallel
effect loop signal with the main dry signal when an
external effect is connected via the effects loop. This
should be set to the “Dry” position when no external
effect is connected.
11. Speaker Jacks for (1) 4 Ohm cabinet or
(2) 8 Ohm cabinets
12. Speaker Jacks for (1) 8 Ohm Cabinet or
(2) 16 Ohm cabinets
13. Speaker Jack for (1) 16 Ohm cabinet.
CAUTION: Do not operate the GT50H without a speaker
cabinet attached to the appropriate speaker jack.
Operating the GT50H without a speaker attached or with
speakers attached to the wrong Ohm rating jacks can
damage the amplifier. Minimum Ohm load for the GT50H
is 4 Ohms. Damage to the GT50H caused by operation
without a speaker cabinet attached or by improper Ohm
load matching is NOT covered under warranty.
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