3.09 / 3.10

3.09 – Settings and Input wiring for current output DAC, balanced Stereo DAC’s, balanced output, 4mA full scale current, 2.5V reference voltage A known example of a DAC requiring these settings is the Analog Devices AD1955. This type of DAC requires the following jumper settings:     The input connections should follow the Scheme shownRead More

3.11 / 3.12

3.11 – Settings and Input wiring for voltage output DAC, stereo, single ended, 1…1.5 VRMS full scale output voltage, 0V reference voltage A known example of a DAC requiring these settings is the Crystal/Cirrus Logic CS4328.   This type of DAC requires the following jumper settings:     The input connections should follow the SchemeRead More

3.13

3.13 – Settings and Input wiring for voltage output DAC, stereo, balanced output, 2…3 VRMS full scale output voltage, 2.5V reference voltage Known examples of DAC’s requiring these settings are:   Analog Devices AD1852, AD1854 Asahi Kasei (AKM) AK4324, AK4382, AK4394, AK4395, AK4396, AK4397 Burr Brown PCM1791, PCM1793, DSD1791, DSD1792 Crystal/Cirrus Logic CS4329, CS4350, CS4390,Read More

3.14

3.14 – Settings and Input wiring for single ended stereo output from voltage output DAC, stereo, balanced output, 2..3 VRMS full scale output voltage, 2.5V reference voltage Known examples of DAC’s requiring these settings are listed under 3.13.   This type of DAC requires the following jumper settings:     The input connections should followRead More

Bias Voltage

Bias voltage A negative bias voltage is needed to prevent runaway current in a vacuum tube. The negative voltage can be applied to the cathode or to the grid.   1. Cathode bias: When applied to the cathode, it becomes self biasing, and the Anode voltage needs to be increased by the amount of voltageRead More

Active Bias Control

Active Bias Control The ideal solution to fixed bias stability is to use an electronic circuit to actively sense current flow through the tube.   Benefits: tube life is extended, saturation of the output transformer is avoided, amplifier always operates optimally, better bass performance, more dynamics, danger of runaway tube current when amplifier is unattended isRead More

ABS Module Features

ABS Module Features Eliminates need for constant re-adjustment of Bias to compensate for mains variations and valve aging Regulation of cathode current of tubes from around 1mA to 250mA with10R cathode resistor current match between halves depends on cathode resistor tolerance ± 1% due to circuit (typical mismatch << 0.1mA). Perfect current balance produces betterRead More