bcaudioAmplifierNo.7Owner’sManual
IMPORTANT SAFETY INSTRUCTIONS
READ, FOLLOW, HEED, AND KEEP ALL INSTRUCTIONS AND WARNINGS.
• DO NOT REMOVE SCREWS ON BOTTOM/REAR. LETHAL VOLTAGES LURK
INSIDE. BOO! CONTACT THE MANUFACTURER FOR SERVICE INFORMATION.
SERVICE MUST BE PERFORMED BY QUALIFIED PERSONNEL.
• THIS AMPLIFIER IS CAPABLE OF PRODUCING HIGH SOUND PRESSURE
LEVELS. CONTINUED EXPOSURE TO HIGH SOUND PRESSURE LEVELS CAN
CAUSE PERMANENT HEARING IMPAIRMENT OR LOSS. WHAT? SPEAK UP!
USER CAUTION IS ADVISED AND EAR PROTECTION IS RECOMMENDED IF
UNIT IS OPERATED AT HIGH VOLUME. WHICH OF COURSE IT SHOULD BE.
• WHEN POWERED ON, THE TUBES MAY BECOME VERY HOT, HOT ENOUGH
TO BURN SKIN ON CONTACT. SO DON’T TOUCH ‘EM. AND KEEP OUT OF
REACH OF CHILDREN AND PETS.
• DO NOT OPERATE WITHOUT SPEAKER OR OTHER SUITABLE LOAD
CONNECTED TO THE SPEAKER JACK, AS DAMAGE MAY RESULT.
• DO NOT OPERATE NEAR ANY HEAT SOURCE.
• DO NOT OPERATE WITH LID IN CLOSED POSITION (MODELS A7 AND A7-240)
OR WITH VENTILATION OPENING(S) COVERED, AS THIS MAY OVERHEAT THE
AMP. DUH.
• DO NOT USE NEAR SPLASHING, FALLING, SPRAYING, OR STANDING
LIQUIDS. AND DON’T EVER LET SOME FOOL SET HIS DRINK ON YOUR RIG.
• CLEAN ONLY WITH A LINT-FREE DRY CLOTH. DO NOT USE CLEANING
AGENTS.
• CONNECT POWER CORD ONLY TO A POLARIZED, SAFETY GROUNDED
OUTLET WIRED TO CURRENT ELECTRICAL CODES AND COMPATIBLE WITH
VOLTAGE, POWER, AND FREQUENCY REQUIREMENTS STATED ON THE
APPLIANCE.
• PROTECT THE POWER CORD FROM DAMAGE DUE TO BEING WALKED ON,
PINCHED OR STRAINED.
• UNPLUG THE APPARATUS DURING LIGHTNING STORMS OR WHEN NOT IS
USE.
• REPLACE FUSE WITH CORRECT TYPE AND RATING AS INDICATED IN THIS
MANUAL AND ON THE APPLIANCE.
• ONLY USE ATTACHMENTS, ACCESSORIES, STANDS, OR BRACKETS
SPECIFIED BY THE MANUFACTURER FOR SAFE OPERATION AND TO AVOID
INJURY.
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OVERVIEW
MAJOR FEATURES
Built by me in the USA
100% All-Tube Signal Path
True Point-to-Point Wiring
Custom Heavy 16ga Powder Coated
Steel Chassis
American-made Paper Bobbin/Paper
Layer Wound Transformers
Stainless Steel Hardware
Tube Rectifier
Class A Cathode Biased Output
Section
Choice of Power Tubes
Octal Preamp
Combination Power/Standby Switch
Bright and Normal Channels
Presence Control
Will Drive Any 8 or 16 Ohm Guitar
Speaker Cabinet
TUBE COMPLEMENT
For 15 Watts*
(1) 5Y3 Rectifier**
(2) 6V6 Power Tubes
(2) 6SL7 Octal Preamp Tubes
For 25 Watts*
(1) 5AR4/GZ34 Rectifier
(2) 5881 Power Tubes
(2) 6SL7 Octal Preamp Tubes
*maximum power into 16 ohms
** If ordered in 15w configuration, your
Amplifier No. 7 is supplied with an
NOS (New Old Stock) 5Y3. If possible,
replace only with an NOS 5Y3. New
production examples do not produce
the ideal B+ voltage for 6V6s.
ESSENTIAL INFORMATION
Tube placement, left to right (facing the front, see diagram, p. 4):
V5 V4 V3 V2 V1
15w Configuration: 5Y3 6V6 6V6 6SL7 6SL7
25w Configuration: GZ34 5881 5881 6SL7 6SL7
Always use the appropriate rectifier tube with your chosen power tubes, as
indicated above. Do not use a GZ34 with 6V6s, as it will shorten their life.
Never use a solid state rectifier replacement module in place of a tube rectifier,
unless it is designed to emulate the rectifier you are replacing, in which case,
why not just use the real thing?
Power (Models A7 and A7HB): 120VAC, 60Hz, 1A
Power (Models A7-240 and A7HB-240): 240VAC, 60Hz, 0.5A
Fuse (Models A7 and A7HB): 2A Slow Blow, Type 3AG, 1/4” x 1-1/4”
Fuse (Models A7-240 and A7HB-240): 1A Slow Blow, Type 3AG, 1/4” x 1-1/4”
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