tubes.lib

Vacuum tube amplifier stage emulations from the Guitarix project. The transfer curve of each tube is stored as a precomputed table (tubetable_*), interpolated at run time; tubestage wraps one table into a complete gain stage with its cathode-capacitor highpass. The T1_*/T2_*/T3_* functions below instantiate the first, second and third preamp stage of each supported tube model.

The models are normally used through their own namespace:

tu = library("tubes.lib");
process = tu.T1_12AX7 : *(preamp) : tu.T2_12AX7;

References

tubestage

tubestage — response plots

One complete triode gain stage: table-driven waveshaping followed by the highpass formed by the cathode capacitor and resistor. tubestageF(tb,vplus,divider,fck,Rk,Vk0) is the fully parameterized form; tubestage(tb,fck,Rk,Vk0) uses the standard 250V supply with divider 40, and tubestage130_20(tb,fck,Rk,Vk0) a 130V supply with divider 20.

Usage

_ : tubestage(tb,fck,Rk,Vk0) : _
_ : tubestage130_20(tb,fck,Rk,Vk0) : _
_ : tubestageF(tb,vplus,divider,fck,Rk,Vk0) : _

Where:

  • tb: a tube transfer-curve table (one of the tubetable_* waveforms)
  • vplus: supply voltage in Volts (tubestageF only)
  • divider: output voltage divider factor (tubestageF only)
  • fck: cutoff frequency in Hz of the cathode highpass
  • Rk: cathode resistor value in Ohms
  • Vk0: quiescent cathode voltage in Volts

T1_12AX7, T2_12AX7, T3_12AX7

T1_12AX7 — response plots

First, second and third preamp stage of a 12AX7 (high-gain dual triode, the classic guitar preamp tube), with the bias values used by the Guitarix amplifiers.

Usage

_ : T1_12AX7 : _

T1_12AT7, T2_12AT7, T3_12AT7

T1_12AT7 — response plots

First, second and third preamp stage of a 12AT7 (medium-gain dual triode), with the bias values used by the Guitarix amplifiers.

Usage

_ : T1_12AT7 : _

T1_12AU7, T2_12AU7, T3_12AU7

T1_12AU7 — response plots

First, second and third preamp stage of a 12AU7 (low-gain dual triode), with the bias values used by the Guitarix amplifiers.

Usage

_ : T1_12AU7 : _

T1_6V6, T2_6V6, T3_6V6

T1_6V6 — response plots

First, second and third preamp stage of a 6V6 (beam power tetrode, wired as a triode), with the bias values used by the Guitarix amplifiers.

Usage

_ : T1_6V6 : _

T1_6DJ8, T2_6DJ8, T3_6DJ8

T1_6DJ8 — response plots

First, second and third preamp stage of a 6DJ8 / ECC88 (low-noise dual triode), with the bias values used by the Guitarix amplifiers.

Usage

_ : T1_6DJ8 : _

T1_6C16, T2_6C16, T3_6C16

T1_6C16 — response plots

First, second and third preamp stage of a 6C16 (single triode), with the bias values used by the Guitarix amplifiers.

Usage

_ : T1_6C16 : _