Solo Golden Tube Audio SE-40 User manual
Golden Tube Audio SE-40
Page 2of 36
Preface ....................................................................................................................................................................3
Document Control...............................................................................................................................................3
SE-40 Original Parts Diagram ..................................................................................................................................4
Left Channel Schematic...........................................................................................................................................5
Power Supply Schematic.........................................................................................................................................6
Original Circuit Board v1.4 –Bottom Side ..............................................................................................................7
Original Circuit Board v1.4 –Top Side ....................................................................................................................8
SE-40 Owner’s Manual............................................................................................................................................9
Biasing the Amp ....................................................................................................................................................20
What is the Proper Bias Set Value?...................................................................................................................20
Before Starting..................................................................................................................................................20
Tools Needed ....................................................................................................................................................20
Removing the Bottom Cover.............................................................................................................................21
Setting the Bias .................................................................................................................................................22
Underneath GTA SE-40 .....................................................................................................................................23
Red Plate Condition ..........................................................................................................................................24
Replacing Tubes ....................................................................................................................................................25
Factory Tubes....................................................................................................................................................25
Factory Output Tube Cross-Reference..............................................................................................................26
Factory Selectable Input Tubes.........................................................................................................................26
Tube Swapping......................................................................................................................................................27
Other 6L6 Varieties ...........................................................................................................................................27
Troubleshooting....................................................................................................................................................28
Dead channel ....................................................................................................................................................28
Hum...................................................................................................................................................................29
Red Glowing Tubes ...........................................................................................................................................29
Low gain ............................................................................................................................................................29
Static Noise .......................................................................................................................................................29
References ............................................................................................................................................................30
Appendix - Sovtek Tube Specs ..............................................................................................................................32
Golden Tube Audio SE-40
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Preface
This service manual is an open source collaboration effort of the members of the Golden Tube community
group at http://groups.yahoo.com/neo/groups/golden_tube/info
This manual is a collection of contributions from various forum members edited and consolidated into on
handy guide to assist in the self-support of maintaining the highly regarded Golden Tube Audio SE-40 amplifier
manufactured by the now defunct Solo Electronics of Hayward California in the 1990’s.
Though the best efforts of the community were involved in making this manual and reviewing and editing it’s
contents, it is possible errors or omissions herein could be present.
As always, proceed with caution and consult a certified technician experienced with tube electronics should
you have any doubts or concerns about your own skill or ability. Even though audio tube technology is 100
years old, thousands of factory new tube audio gear is sold annually. Consult Ham radio shops, guitar shops,
and specialty Hifi shops to locate a qualified technician in town.
Document Control
Version
Published
Date
Change Control
1.0
09-10-2013
First version follow draft review
1.1
09-10-2013
Added Sovtek Tube Specification section
1.2
09-23-2013
Edited Tube Cross-ref section for clarity; within Reference section added Parts
suppliers
1.3
09-27-2013
Selectively edited for grammar and clarity, resolved a broken link, replacement
tube cross-reference chart
Golden Tube Audio SE-40
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SE-40 Original Parts Diagram
Parts Placement and Key Test Points
Golden Tube Audio SE-40
Page 5of 36
Left Channel Schematic
GTA built versions from 1.0 to 1.4. It’s unknown which version this schematic pertains. There is debate how
accurate this drawing may be or for which version.
Table of contents
