It is recommended to only use exact replacement tubes similar to what is installed at the factory.
Be careful when deciding to install other types of 6L6, 6V6, or EL-34 based tubes. Not all have the
same specs and some can’t handle the plate voltage of the amplifier.
Below is a limited list of comparable tube types:
6L6: 6L6GC, 7581, 5881
6V6: 6V6S, 6V6GT
EL-34: 6CA7
Bias Ranges: Are measured and set in Volts. But can be measured and set in milliamps.
Numbers given are for 2 or 4 tubes combined.
6L6 and EL-34 type tubes: .060V to .070V for 35watt and 50watt Factory Setting: .064V
.1200V to .1400V for 100watt
Factory Setting: .1260V
6V6: Installed in the 22watt versions only: .044V to .058V Factory Setting: .054V
6V6: Installed in 22watt versions with tremolo, bias must not be set higher then .044V as it will
cause tube failure.
Do not set bias higher then recommend levels as it can lead to tube failure or failure within the
amplifier!
WARNING!
No user serviceable parts inside! Refer to qualified service person only.
LINE CORD- For your safety, connect to grounded A/C receptacle only.
Summary of Contents for Two-Rock Studio Pro 22
Page 1: ...OWNER S MANUAL ...
Page 9: ......
