AUDIO ELECTRONICS Super Amp MKII Operation Manual - Operation
OPERATION
9
Your new Super Amp MKII is ready for operation after the speaker, interconnect cables and tubes
have been installed.
Signal input connection is made via the input jack on the rear of the
amplifier located next to the output binding posts. The interconnect cables from the output of the
preamplifier can be any convenient length your set-up requires. The choice of a high quality
interconnect cable is important. Once again, your audio dealer will have the proper cables in
stock for this purpose.
AC ON POWER SWITCH
Rotate the AC power switch to the right. The amplifier will turn ON, and the blue and red LED’s
will light. The B+ voltage along with appropriate bias voltage will power up. The blue LED is an
indication of filament voltage and the red LED is an indication the B+ plate voltage is operating.
BIAS MEASUREMENT
Your new Super Amp MKII has come from the factory with pre-adjusted bias setting. Since all AC
wall outlet voltages vary according to location, you need to check and/or reset the tube bias
current. This is a simple procedure using the supplied bias jack cord set that came with your
Super Amp MKII.
An analog or digital multi-meter is required to perform this test and setting.
PLEASE NOTE
THE TEST METER MUST BE IN THE DC MA. CURRENT POSITION! FAILURE TO USE
THE DC CURRENT READING WILL RESULT IN DAMAGE TO THE OUTPUT TUBES
BECAUSE OF IMPROPER READINGS!
Follow the steps listed below.
Initial bias check: Plug the ¼” male bias plug into the rear apron bias jack. Hook the red
alligator clip to the positive test lead of a digital or analogue test meter. Hook the black alligator
clip to the negative test probe of the meter. Make sure the meter is in the DC CURRENT range.
This is very important… if the meter is set in the DC voltage position the reading will be
completely wrong. Please check and double check to make sure you are in DC current mode.
Turn on the Super Amp MKII with the front panel AC power switch. As the amplifier warms up
you will notice the DC current readings. The basic operation range should be 200 ma. DC current
after five minutes of operation. This value will vary plus or minus 10 to 15 ma. with changing AC
wall socket voltages. This is normal and does not change the basic performance of your Super
Amp MKII.
Bias Adjust: Use a conventional flat blade screw driver to rotate the bias adjustment pot on the
rear of the Super Amp MKII. Turning the pot to the right (clockwise) will increase the bias current
setting. Turning the pot to the left (counter clockwise) will decrease the bias current setting.
New Tube Bias: When replacing output tubes or simply “tube rolling” with different types of
output tubes please start the bias procedure as above with the initial setting of the bias pot in
the full counter clockwise (left) position. This is the zero (0) bias setting. After the amplifier has
warmed up for a few minutes rotate the bias pot slowly in a clockwise direction to the 200 ma.
setting on a DC current meter.