Ayon Crossfire - BIAS ADJUSTMENT; Power Tube Bias Adjustment

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Ayon Audio – Hart 18 – 8101 Gratkorn – Austria – Phone: +43 3124 24954
www.ayonaudio.com
F. The Crossfire amplifier SHOULD NOT BE LEFT RUNNING WHEN NOT IN USE.
If you will not be listening to the amplifier for more than an hour, it is advised that the amplifier
be turned off. Unlike solid state amplifiers, tube amplifiers should be shut down when not being
used. This will greatly prolong tube life.
G. It is normal for vacuum tube equipment to run very warm if used for prolonged periods.
H. Do not use a speaker with impedance lower than 2 ohms on either of the outputs.
Note: NEVER REMOVE THE BOTTOM PLATE OF THE CROSSFIRE BEFORE UNPLUGGING THE UNIT
FROM THE WALL!
6. Bias adjustment – important!
The output power tubes need to be “biased” with a grid voltage that controls the flow of
electrical current through the tube. Tube biasing on the amplifier has been designed to be
both simple and effective. The bias is set individually for each tube so that the correct
operating point is assured. An added benefit to this approach is that, should a tube fail
prematurely, the single tube can be replaced without having to purchase a matched set.
Use the following procedure to set the tube bias:
To adjust bias of tube V1 switch the bias selector to position “Bias 1”.
Adjust bias 1 with potentiometer at 110mV – 120mV.
To adjust bias of tube V2 switch the bias selector to position “Bias 2”.
Adjust bias 2 with potentiometer at 110mV – 120mV.
Important: Please check the bias voltage several times during the first 20 minutes of warm up
and adjust if necessary to the recommended value.
Important notice for new tubes or new amplifier: When using the amplifier for the first time or
after any exchange of the AA62B tubes, the bias voltage for the AA62B tubes should be set to
around 80mV and the amplifier should be run with this value for some hours to allow for a
smooth initial run-in of the tubes. After completion of this "warm up" phase, the bias should be
slowly increased towards the optimal value of 110 -120mV.
bias adjustment