Millennia STT-1 Balancing Tube Preamp - Manual

Millennia Media, Inc. 4200 Day Spring Ct. Placerville, CA 95667
Balancing the STT-1 tube preamp
CAUTION HIGH VOLTAGE
This should only be done by trained personnel
When replacing V1 (12AX7) in the STT-1, you must make an adjustment to
the unit.
1. Let unit warm up for 20 minutes.
2. Turn the Vacuum Tube Gain pot full counter clockwise.
3. Place a DC volt meter from R85 to R88 (the ends of the resistors that
are closest to the front of the unit.)
4. Adjust VR4 (near V1) to achieve minimum voltage. Should be near .05
volts or less.
5. Turn the Vacuum Tube Gain pot to full clockwise. The voltage may
change. Let it sit at full gain for 10 seconds or so and then turn back
to minimum gain and using R4, null the voltage between R85 and R88.
Do this a few times and when it is balanced there should be not much
change from low to full gain.
VR4
V1
R85
R88
http://www.mil-media.com (530) 647-0750 Fax (530) 647-9921