Siegmund Big Boy 330, Руководство пользователя

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Bias Control Bias Control Bias Control Bias Control
To achieve maximum performance while giving longest tube life, the Big Boy
Big Boy Big Boy
Big Boy features a complete easy-
access Bias Control Bias Control Bias Control Bias Control section, with test-points for DVM hook-up.
Here is a simple guide for adjusting bias:
No technical knowledge is required.
All we need is a
D igital V olt M eter, which reads DC millivolts (mV).
L … Left Tube G … Ground R … Right Tube
Bias:
1 Follow the power-up procedure.
2 Play the amp for about 30 minutes or until the tubes are completely warmed up.
3 Turn the Master volume all the way down.
4 Switch the DVM to the DC millivolts setting. (200mV on most units)
5 Insert the Black probe of the DVM into the G test-point.
6 Insert the R
ed
probe into
L
and adjust the
Bias
trim below it to the number shown in the table on the next page.
7 Insert the Red probe into R and again adjust Bias trim below it to the same number.
8 Repeat steps 6 and 7 until both sides have stabilized at the same number.
Balance:
1 Insert the Black probe into L and the Red probe into R
The meter reading is now the difference between
L
and
R
2 Play one single note or chord with the amp in your favorite front panel knob settings and adjust Balance
to a reading close to Zero.