Tube Complement; Bias Adjustments - K&M Analog Designs Two-Rack TS-1 Owner's Manual

V1- 12AX7, Rhythm channel
V2- 12AX7, Lead Channel
V3- 12AX7. Phase Inverter
V4-V7- 6L6GC, Output OR EL34
*V6, V7- 5AR4 (50 Watt Tube Rectified)
Each fine production tube is tested and matched to our exacting specifications. External bias adjustment and
test points are located on the chassis near the output tube sockets. A digital voltmeter and small screwdriver are
required for bias adjustment.

BIAS ADJUSTMENTS:

Power up unit and connect proper speaker load.
Set master volumes and effects return controls to zero.
DO NOT apply any signal to the input during the biasing procedure!
Take unit off standby and allow a few seconds for the circuit to stabilize.
Set voltmeter to Millivolt scale (or lowest volt scale 60 millivolts=.060 volts.)
With meter grounded to chassis and + probe at test point, measure voltage.
A reading of 0.100 to 0.120 volts is normal for 100 Watt amplifiers with (4) 6L6's.
Do not set above .140!
For other tube types (5881, 6550, EL34) check with the manufacturer or contact us for recommendations.
Settings higher than .130 with 6L6 tubes may cause premature tube wear and possibly damage the amplifier.
Keep in mind that tubes vary in quality, and some tubes can handle upwards of 40 ma each (a reading at the test
point of .160!) However, to be on the safe side, use the above as a guide.
WARNING! No user serviceable parts inside! Refer to qualified service person only.
LINE CORD- For your safety, connect to grounded A/C receptacle only.

Tube Complement