B-52 AT-112 User manual

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INSIDE THIS INSTRUCTION MANUAL
Important Safety Instructions / Features .....2
Product Information .......................................3
AT-112 Controls ..............................................4-5
Warranty Information .....................................5-7
Contact Information .......................................8
HEED ALL WARNINGS!
WARNING: To reduce the risk or fire or
electrical shock do not expose this
equipment to rain or moisture.
1) Read these instructions.
2) Follow all instructions.
3) Keep these instructions.
4) Heed all warnings.
5) DO NOT turn on the AT-112 without the
loudspeaker connected.
6) Do not use the AT-112 near water. Be extra
cautious when moving the AT-112 during
rain or while transporting it over wet surfaces
as water might splash onto the amplifier.
6) Clean only with dry cloth.
7) Do not block any ventilation openings and
operate in accordance with manufacturer’s
instructions.
8) Do not install near heat sources such as
radiators, stoves or other devices that may
produce heat.
9) Do not defeat the safety purpose of the
polarization 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 is provided for your
safety. If the provided plug does not fit your
outlet, consult an electrician for replacement
of the obsolete outlet.
10) Protect the power cord from being walked on
or pinched, particularly at the plug and the
point where it exits the AT-112 amplifier.
11) Only use attachments / accessories specified
by B-52 Professional.
12) Unplug the AT-112 during lightning storms
and when not in use.
13) Refer all servicing to qualified personnel.
Servicing is required when the AT-112 has
been damaged in any way such as when
power-cord or plug is damaged, liquid has
been spilled into the amplifier, the unit has
been exposed to moisture or rain, does not
operate normally, or has been dropped.
14) To reduce the risk of fire or electric shock, do
not expose the AT-112 to rain or moisture.
15) Moisture can damage the AT-112 and can
cause corrosion of electrical contacts.
16) Keep the unit out of extended or intense
direct sun light. No containers filled with any
type of liquid should be placed on or near the
AT-112.
17) Never remove the front or rear panels of
the AT-112 while it is connected to an
electrical outlet.
IMPORTANT SAFETY
INSTRUCTIONS!
This AT-112 is a 2 channel, all-tube combo that gives
you unparalleled tone and astounding versatility. The
clean channel yields sparkling vintage tone that stays
clean even at high volume. The overdrive channel
unleashes a modern high gain assault seldom found in
a compact combo. The contour (mid-scoop) control
gives you astounding control over the all important
midrange. The Global section features Low-Res
(Resonance) and Reverb controls.
lAll-Tube preamp/poweramp signal path
lOverdrive Channel: Gain and Master controls, 3 band EQ
and Contour.
lClean Channel: Master Volume with 3-Band EQ.
lGlobal Controls: Low-Res (Resonance) and Reverb
lEffects Loop with Level Controls
lLine Out with Level Control
lSelectable 4 / 8 / 16 Ohms External Speaker Jacks
l2-Position Footswitch: Channel Select and Reverb.
lRugged 18mm Baltic birch construction
lDetachable casters for easy transport
lDimensions: 22.5” (W) x 19.5” (H) x 11” (D)
lWeight: 40lbs.
AT-112 ALL-TUBE COMBO

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AT-112 TUBES
Power amp: 2 x 6L6 / 5881
1 x 12AX7
Preamp Tubes: 4 x 12AX7
HEARING DAMAGE, PROLONGED EXPOSURE TO EXCESSIVE SPL
B-52 Professional amplifiers and speakers, including the AT-112, are capable of producing sound pressure levels (SPL) sufficient to cause
permanent hearing damage to performers, production crews or people in the audience. Hearing protection devices such ear-plugs are rec-
ommended. Caution should be taken to avoid extended SPL is excess of 90 dBA.
PRECAUTIONS
Do not attempt to service the AT-112 by yourself. Refer all servicing to a B-52 Authorized service dealer. Service is required when the
AT-112 has had liquid spilled on or inside the unit, has been damaged in any way, has been exposed to rain or moisture, does not operate
normally or has been dropped.
WARNING – SHOCK HAZARD:
To reduce the risk of fire or electrical shock, do not expose this unit to rain or moisture. Do not operate your AT-112 near a pool or other
standing water. Make sure all blades on the polarized power plug are fully inserted into the power source. Ensure the power cord is not
stretched, pinched or otherwise abused. Ensure the power cord is routed to avoid foot traffic. Your AT-112 amplifier should be cleaned only
with a dry cloth.
AT-112 60-WATT ALL-TUBE 12” COMBO!
THANK YOU FOR CHOOSING THE B-52 PROFESSIONAL AT-112 COMBO!
The AT-112 is a straight forward, all-tube powerhouse with 60 relentless watts ripping
through a custom-built B-52 - 12” loudspeaker.The AT-112's foundation is outstanding tone,
versatility and power. Each channel - Clean and Overdrive - has its own set of gain, treble,
mid and bass equalization controls for maximum flexibility.
The Clean Channel offers a broad palette of classic and modern tones. The Overdrive
Channel features a wide range of tones ranging from bluesy grit to all out metallic shred.
The contour control “scoops” the all important mids, effectively producing the ultimate metal
tone or, when turned up, creates the warm, full bodied tones of the great classic amps.
The AT-112 also features solid Baltic birch construction and a two function heavy-duty
footswitch.
Power Handling: 120 watts
Freq. Response: 50-5K Hz
Nominal Impedance: 8 Ohms
Voice Coil Diameter: 2.5”
CUSTOM B-52 TRANSDUCER

1. INPUT: Plug your guitar in here. Always use a high-quality,
shielded instrument cable.
2. OVERDRIVE CHANNEL - GAIN: Adjusts the amount of
Drive or Distortion.
3. OVERDRIVE CHANNEL - BASS: Adjusts the amount of low
frequency boost or cut as desired in the overdrive channel.
Bass is B-52's signature. Turning this control clockwise
increases depth and low-end punch.
4. OVERDRIVE CHANNEL - MIDDLE: Adjusts the amount of
mid-range frequencies as desired in the overdrive channel.
The Middle control adds body and punch to your sound.
5. OVERDRIVE CHANNEL - TREBLE: Adjusts the amount of
high frequency boost or cut as desired in the overdrive
channel. Turning this control clockwise adds clarity.
6. OVERDRIVE CHANNEL - CONTOUR: Varies the critical
midrange tone in the overdrive channels. Adjusts from “classic”
midrange punch to “scooped metal” madness.
7. OVERDRIVE - VOLUME: Controls the overall loudness of the
channel.
8. CHANNEL SELECT: Push switch selects between the clean
and overdrive channels. Activated LED lights indicate which
channel is in use.
9. CLEAN CHANNEL - BASS: Adjusts the amount of low
frequency boost or cut as desired. Adding bass will increase
the depth and fullness of your sound.
18. AC INLET & PRIMARY FUSE: Connects AC powercord and
houses primary fuse.
Always use correct value as indicated on amp panel chart.
19. POWER TUBE FUSE: This fuse protects the AT-112 against
circuit damage caused by a power tube failure. Only replace
with a 1 AMP Fast Blo (never Slo Blo) fuse.
20. LOUDSPEAKER OUTPUTS: Connects the AT-112 to the
internal 12” speaker.The extension output can be connected to
an additional speaker enclosure. Be sure the impedance switch is
properly set. The correct setting for the AT-112 is 8 ohms when
no extension speaker is connected. NOTE: Always be sure the
speakers are plugged in before attempting to operate the amplifier. Severe
damage can occur from failing to connect the speakers to a tube amplifier.
21. IMPEDANCE SELECTOR SWITCH: Allows the AT- 112 to
safely operate into any 4 ohm, 8 ohm or 16 ohms.
NOTE: Proper setting of the switch is critical for reliable operation.
To reduce the risk of fire or electrical shock, do not expose this unit to rain
or moisture. Do not operate your AT-112 near a pool or other standing
water. Make sure all blades on the polarized power plug are fully inserted
into the power source. Ensure the powercord is not stretched, pinched or
otherwise abused. Ensure the power cord is routed to avoid foot traffic.
Your AT-112 amplifier should be cleaned only with a dry cloth.
WARNING: SHOCK HAZARD!
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AT-112 CONTROLS AND FEATURES

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22. LINE OUT LEVEL CONTROL: Controls the signal level of
the Line Out Jack.
23. LINE OUT JACK: Connects the AT- 112 to an external
line-level device.
24. FOOTSWITCH - CHANNEL/REVERB: Connects footswitch to
turn the reverb on/off and to switch between the Clean and
Overdrive channels.
25. EFFECTS - RETURN JACK: Connects the AT-112 to the
output of an effects unit.
26. EFFECTS - RETURN LEVEL: Controls the input level of
the returning signal from an effects unit.
27. EFFECTS - SEND LEVEL: Controls the signal level output
to an effects unit.
28. EFFECTS - SEND JACK: Connects to the AT-112 to the input
of an effects unit.
10. CLEAN CHANNEL - MIDDLE: Adjusts the amount of mid-
range frequencies as desired in the clean channel. Turning the
middle control clockwise will increase the amount of warmth in
your tone. Counterclockwise settings create a more pristine,
acoustic kind of sound.
11. CLEAN CHANNEL - TREBLE: Adjusts the amount of high
frequency boost or cut as desired in the clean channel. Turning
this control clockwise will add brilliance to your sound. Turning
the control counter-clockwise softens the tone.
12. CLEAN CHANNEL - VOLUME: Controls the overall loudness
of the clean channel.
13. MASTER LOW RESONANCE: Controls the overall resonance
of the amplifier. Turning the control clockwise adds rich low end.
14. MASTER REVERB CONTROL: Adjusts the amount of reverb
produced by the amplifier. To increase the amount of reverb
turn clockwise.
15. PILOT JEWEL: Power on indicator.
16. STANDBY ON/OFF SWITCH: Allows the AT-112 to remain
turned ON for limited periods of inactivity. When the Standby
switch is in the STANDBY position the AT-112 is in a non-
operational setting. When in Standby the tubes remain
hot and ready for use. This bypasses the time required for the
tubes to warm up before use. When the Standby switch is in
the ON position the AT-112 is operational. DO NOT turn on the
AT-112 or have the switch set to ON without it connected
to a loudspeaker.
17. POWER ON/OFF SWITCH: Turns the AT-112 on and off.
Do not attempt to service the
AT-112 by yourself. Refer all
servicing to a B-52 Authorized
d e a l e r. Service is required
when the AT-112 has had liquid
spilled on it or has been dam -
aged in any way, the amplifier
has been exposed to rain or
moisture, does not operate
normally or has been dropped.
PRECAUTIONS
AT-112 CONTROLS AND FEATURES

LIMITED WARRANTY
Thank you for choosing a B-52 sound product. B-52 manufactures some of
the world’s best sounding and most reliable professional speaker systems,
amplifiers and components. E.T.I. Sound Systems, Inc., makers of B-52, takes
great pride in thoroughly testing each B-52 product prior to shipment.
B-52 CABINETS: E.T.I. Sound Systems, Inc. offers a LIFETIME warranty
(effective January 1, 2002) to the original purchaser that a B-52's cabinet
construction will be free from defects in material and workmanship. A dated
sales receipt will establish coverage under this warranty.This warranty does
not cover service or parts to repair damage caused by neglect, abuse, nor-
mal & wear and cosmetic appearance of the cabinetry not directly attributed
to defects in material or workmanship, or service, repair, modifications of the
cabinet, which has not been authorized or approved by E.T.I. If this product
is defective in materials or workmanship as warranted above, your sole rem-
edy shall be repair or replacement as provided above.
LOUDSPEAKER AND MID-RANGE COMPONENTS: E . T.I. Sound
Systems, Inc. warrants the original purchaser that B-52 loudspeakers and/or
midrange components will be free from defects in material and workmanship
for a period of (5) FIVE YEARS from the original purchase date (effective
January 1, 2002). Adated sales receipt will establish coverage under this
warranty. This warranty will automatically terminate (5) years after the origi-
nal retail sales date. This (5) five-year warranty does not cover service or
parts to repair damage caused by accident, disaster, misuse, abuse, burnt
voice-coils, over-powering, negligence, inadequate packing or shipping pro-
cedures and service, repair or modifications of the component which has not
been authorized or approved by E.T.I.. This warranty is in lieu of all other
expressed warranties. If this product is defective in materials or workman-
ship as warranted above, your sole remedy shall be repair or replacement
as provided above.
HIGH-FREQUENCY DEVICES: E.T.I. Sound Systems, Inc. offers a LIFE-
TIME warranty (effective January 1, 2002) to the original purchaser that
B-52 high frequency (tweeters) devices will be free from defects in material
and workmanship. Adated sales receipt will establish coverage under this
warranty. This warranty does not warranty neglect or abuse. NO WARRAN-
TY IS OFFERED ON HIGH-FREQUENCY DEVICES IN B-52 SYSTEMS
WITH A BI-AMP SWITCH OPTION.The lifetime warranty on high-frequen-
cy devices does not cover service or parts to repair damage caused by acci-
dent, disaster, misuse, abuse, negligence, inadequate packing or shipping
procedures or service, repair or modifications of the product which has not
been authorized or approved by E.T.I. This warranty is in lieu of all other
expressed warranties. If this product is defective in materials or workman-
ship as warranted above, your sole remedy shall be repair or replacement
as provided above.
GUITAR AMPLIFIERS: E.T.I. Sound Systems, Inc. warrants the original pur-
chaser that B-52 guitar amplifiers will be free from defects in material and
workmanship for a period of (5) FIVE YEARS from the original purchase date
(effective January 1, 2002). Adated sales receipt will establish coverage
under this warranty.This warranty will automatically terminate (5) years after
the original retail sales date. This (5) five-year warranty does not cover serv-
ice or parts to repair damage caused by accident, disaster, misuse, abuse,
over-powering, negligence, inadequate packing or shipping procedures and
service, repair or modifications of the amplifier which has not been author-
ized or approved by E.T.I.. This warranty is in lieu of all other expressed war-
ranties. If this product is defective in materials or workmanship as warranted
above, your sole remedy shall be repair or replacement as provided above.
GUITAR AMPLIFIER TUBES: E.T.I. Sound Systems, Inc. warrants the orig-
inal purchaser that amplifier tubes used in B-52 Stealth Series All-Tube
Amplifiers will be free from defects in material and workmanship for a period
of 90 DAYS from the original date of purchase (effective January 1, 2002). A
dated sales receipt will establish coverage under this warranty.This
warranty will automatically terminate 90 Days after the original retail sales
date. This 90-Day warranty does not cover service or parts to repair damage
caused by accident, disaster, misuse, abuse, over-powering, negligence,
inadequate packing or shipping procedures and service, repair or modifica-
tions of the amplifier which has not been authorized or approved by E.T.I..
This warranty is in lieu of all other expressed warranties. If this product is
defective in materials or workmanship as warranted above, your sole reme-
dy shall be repair or replacement as provided above.
RETURN PROCEDURES: In the unlikely event that a defect should occur,
follow the procedure outlined below. Defective products must be shipped,
together with proof of purchase, freight pre-paid and insured to the
Authorized B-52 Dealer from whom you purchased the product or directly to
E.T.I. Sound Systems. If a product must be returned to E.T.I. Sound Systems
for warranty replacement/repair, a Return Authorization Number must be
obtained from our Customer Service Department prior to shipping the prod-
uct.
NEVER RETURN THE ENTIRE CABINET_ _JUST THE DEFECTIVE COM -
PONENT. Identify and remove the defective component. If you are uncertain
which component is defective, or need directions for removing a component,
please contact our Customer Service Department for assistance.
Components which are a part of an original B-52 speaker box must be sent
directly to E.T.I. Products must be shipped in the original packaging or its
equivalent; in any case, the risk of loss or damage in transit is to be borne
by the purchaser.The Return Authorization Number must appear in large
print directly below the shipping address. Always include a brief description
of the defect, along with your correct return address and telephone number.
When calling to inquire about a returned product, always refer to the Return
Authorization Number. If E.T.I. determines that the unit was defective in
materials or workmanship at any time during the warranty period, E.T.I. has
the option of repairing or replacing the product at no additional charge,
except as set forth below.All replaced parts become a property of E.T.I.
Products replaced or repaired under this warranty will be returned via
ground-shipping-within the United States-freight prepaid. E . T.I. is not
responsible for costs associated with expedited shipping, either to
E.T.I. or the return of the product to the customer.
INCIDENTAL OR CONSEQUENTIAL DAMAGE: In no event will E.T.I. be
liable for any incidental or consequential damages arising out of the use or
inability to use of any B-52 product, even if E.T.I. or a B-52 dealer has been
advised of the possibility of such damages, or any other claim by any other
party. Some states do not allow the exclusion or limitation of consequential
damages, so the above limitation and exclusion may not apply to you. This
warranty gives you specific legal rights and you may also have other rights
which may vary from state to state.
FOR YOUR PROTECTION: Please complete and mail the Purchase
Information Card within (10) ten days of the date of purchase so that we
may contact you directly in the event a safety notification issued in accor-
dance with the 1972 Consumer Product Safety Act. In addition, we ask that
you complete the brief questionnaire so me may analyze your answers and
in this way, help us evaluate our customer needs.
CUSTOMER SERVICE: Our dedicated staff is ready to help you with any
B-52 warranty or product questions you may have. Please call 323-277-4100
(9:00AM to 4:00PM Pacific Standard Time, United States).
E.T.I. Sound Systems, INC.
3383 Gage Ave., Huntington Park, CA, 90255
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3383 Gage Avenue, Huntington Park, CA, 90255
Phone: [phone] Fax: [phone]
National: 1-800-344-4384
Internet: www.B-52GUITAR.com
E-mail: [email protected]
E.T.I. Sound Systems is dedicated to product excellence and therefore continuously attempts to improve each and every model we
manufacture. This ongoing process includes refinements in design, materials and workmanship, which may result in products that
differ than those described in our literature. All features, specifications, and prices are therefore subject to change without notice.
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