Instruction Manual

MIG-50 MKII
50W All Tube Guitar Amplifier
Congratulations on your purchase of the Electro-Harmonix MIG-50 MKII, an all tube,
two channel, 50W guitar amplifier head. The EHX MIG-50 MKII is a reissue of the
Sovtek MIG-50 with modern enhancements to both the electronics and mechnical
design. The MKII circuit also improves upon previous iterations of the EHX MIG-50
reissue by overhauling the BRIGHT channel, tonestack, power amp, negative feedback,
and the power supply to produce our best sounding and most reliable MIG-50 yet! The
MIG-50 MKII comes installed with three 12AX7 preamp tubes and two 5881 power
tubes.
TABLE OF CONTENTS
Important Safety Instructions .............................................. 1
Getting Started ................................................................... 3
Front Panel ......................................................................... 3
Rear Panel .......................................................................... 4
How to Adjust Power Tube Bias ........................................... 4
Tube Amplifier Basics & Maintenance ................................... 6
Warranty Info ..................................................................... 8
IMPORTANT SAFETY INSTRUCTIONS
 Read these instructions.
 Keep these instructions.
 Heed all warnings.
 Follow all instructions.
 Clean only with a dry cloth.
 Do not block any ventilation openings.
 Do not install near any heat sources such as radiators, heat registers, stoves, or
other apparatus (including amplifiers) that produce heat.
 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.
 Protect the power cord from being walked on or pinched.
 Unplug this amplifier during lightning storms or when unused for long periods of
time.
 WARNING: To reduce the risk of fire or electric shock, do not expose this
apparatus to rain or moisture.
 Do not expose this apparatus to dripping or splashing and ensure that no object
filled with liquids is placed on the equipment.
 Maintain at least six inches of unobstructed air space behind the unit to allow for
proper ventilation and cooling. Air must be capable of freely moving around the
amplifier.
 This amplifier is capable of producing very high sound pressure levels which may
cause temporary or permanent hearing damage. Use care when adjusting volume
levels during use.
 Do not turn the amplifier on without a loudspeaker.
 Refer all servicing and maintenance to qualified service personnel including
replacement of fuses and vacuum tubes. Changes and modifications not expressly
approved by EHX can void the warranty.
 DO NOT attempt to remove the amplifier chassis. There are no serviceable parts.
 DO NOT use this apparatus near water.
 Servicing is required when the apparatus has been damaged in any way, such as
power-supply cord or plug is damaged, liquid has been spilled or objects have
fallen into the apparatus, the apparatus has been exposed to rain or moisture,
does not operate normally, or has been dropped.
 The ventilation should not be impeded by covering the ventilation openings with
items, such as newspapers, tablecloths, curtains, etc.
 No naked flame sources, such as lighted candles, should be placed on the
apparatus.
 Apparatus is not for use in tropical climates.
 Only use attachments/accessories specified by the manufacturer.
 The appliance coupler shall remain readily operable.

The lightning flash with arrowhead symbol within an equilateral triangle, is intended to alert
the user to the presence of uninsulated “dangerous voltage” within the product’s enclosure
that may be of sufficient magnitude to constitute a risk of electric shock to persons.
The exclamation point within an equilateral triangle is intended to alert the user to the
presence of important operation and maintenance (servicing) instructions in the literature
accompanying the product.
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