Useful Sub circuits. This text file contains verbal descriptions of each circuit followed by the netlist of it. These can't be used in this form. You must copy the netlist for each circuit, and then paste it into another instance of the text processor. Then save it under the name given in the header including the .sub extension. If this sounds familiar, it is the same procedure you performed on the tube models you downloaded in lesson 4. Two band response control circuit with 100 k ohm pots. Bass branch. The left side of the RCC, response control circuit goes to a 22 k ohm resistor. The other end of the 22 k goes to the clockwise end of a 100 k ohm pot, bass control. There is a 0.01 u f cap connected from one end of the pot to the other. The wiper of the pot goes to one end of a 300 k ohm res. The other end goes to the center of the circuit.. The counter clockwise end of the bass pot goes to one end of another 22 k ohm resistor. The other end of the resistor goes to the right side of the circuit. Treble branch. The left side of the response control circuit also goes to a 680 pf cap. The other end of the cap goes to the clockwise end of a 100 k ohm pot, treble control. The wiper of the pot goes to one end of a 150 k ohm resistor. The other end of the resistor goes to the center of the circuit. The counter clockwise end of the treble pot goes to another 680 p f capacitor. The other end of the cap goes to the right side of the RCC, (Response control circuit). End verbal description. * C:\Users\Your Name\Documents\LTspiceXVII\Audio\MM-2-B-100K.sub * Two band RCC (Response Control Circuit) with 100 k ohm pots. .subckt MM-2-B-100K L C R ; Left, Center, and Right, instead of input, grid, and output. * Bass branch. R1 N001 L 22k ; Bass shelving resistor. R2 N002 N001 {BPp*(2-Pv)+Pv-1} ; CW side of bass pot. Pv = pot value, BPp = bass pot position. R3 N003 N002 {BPp*(Pv-2)+1} ; CCW side of bass pot. C1 N003 N001 .01u ; Bass corner frequency. R4 C N002 300k ; Pot loading limiting resistor. R5 R N003 22k ; Other bass shelving resistor. * Treble branch. C2 N004 L 680p ; Treble corner frequency. R6 N005 N004 {TPp*(2-Pv)+Pv-1} ; CW side of treble pot. Pv = pot value, TPp = treble pot position. R7 N006 N005 {TPp*(Pv-2)+1} ; CCW side of treble pot. R8 N005 C 150k ; Pot loading limiting resistor. C3 R N006 680p ; Treble corner frequency. .ends Two band response control circuit with 250 k ohm pots. Bass branch. The left side of the RCC goes through a 56 k ohm resistor to the CW end of the bass control, 250 k ohms. The CCW end goes through another 56 k ohm res to the right side of the RCC. There is a 0.0022 u f cap connected from one end of the bass pot to the other. The wiper of the bass pot goes through a 1 meg ohm resistor to the center of the RCC. Treble branch. The left side of the RCC also goes through a 24 k ohm resistor then to one end of a 220 p f capacitor. The other end of the capacitor connects to the CW end of the treble control, 250 k ohm pot. The CCW end of the treble control goes to another 220 p f cap. The other end goes through another 24 k ohm res to the right side of the RCC. The wiper of the treble pot goes through a 220 k ohm resistor to the center of the RCC. * C:\Users\Your name\Documents\LTspiceXVII\Audio\MM-2-B-250k.sub * Two band RCC (Response Control Circuit) with 250 k ohm pots. .subckt MM-2-B-250k L C R ; Left, Center, and Right, instead of input, grid, and output. * Bass branch. R1 N001 L 56k ; Bass shelving resistor. R2 N002 N001 {BPp*(2-Pv)+Pv-1} ; CW side of bass pot. Pv = pot value, BPp = bass pot position. R3 N003 N002 {BPp*(Pv-2)+1} ; CCW side of bass pot. R4 R N003 56k ; Bass shelving resistor. C1 N003 N001 0.0022uf ; Bass corner frequency. R5 C N002 1Meg ; Pot loading limiter. * Treble branch. R6 N004 L 24k ; Treble shelving. C2 N005 N004 220pf R7 N006 N005 {TPp*(2-Pv)+Pv-1} ; CW side of treble pot. Pv = pot value, TPp = treble pot position. R8 N007 N006 {TPp*(Pv-2)+1} ; CCW side of treble pot. R9 N006 C 220k ; Pot loading limiter. C3 N008 N007 220pf ; Treble corner frequency. R10 R N008 24k ; Treble shelving resistor. .ends Three band response control circuit with 100 k ohm pots. Bass branch. One end of a 10 k ohm resistor goes to the left side of the RCC. The other end goes to the clockwise end of the bass pot, 100 k ohm. The other end goes to another 10 k ohm resistor to the right side of the RCC. There is a 0.056 u f cap connected from one end to the other of the bass pot. The wiper goes through a 100 k ohm resistor to the center of the RCC. Midrange branch. Another 10 k ohm resistor goes from the left side of the RCC to the clockwise end of the midrange pot, 100 k ohm. The other end of this pot goes through another 10 k ohm resistor to the right side. There is a 1600 pf capacitor connected from one end of the midrange pot to the other. The wiper of the midrange pot goes through a 3300 pf capacitor then a 100 k ohm resistor to the center of the RCC. Treble branch. One end of a 1 nf, 0.001 u f capacitor connects to the left side of the RCC. The other end of the capacitor connects to the clockwise end of the treble pot, 100 k ohm. The other end of this pot connects to one end of another 1 nf cap. The other end goes to the right side of the response control circuit. The wiper of the treble pot goes through a 47 k ohm resistor to the center of the RCC. * C:\Users\Your Name\Documents\LTspiceXVII\Audio\MM-3-B-100k.sub * Three band RCC (Response Control Circuit) with 100 k ohm pots. .subckt MM-3-B-100k L C R ; Left, Center, and Right, instead of input, grid, and output. * Bass branch. R1 N001 L 10k ; Bass shelving. R2 N002 N001 {BPp*(2-Pv)+Pv-1} ; CW side of bass pot. Pv = pot value, BPp = bass pot position. R3 N003 N002 {BPp*(Pv-2)+1} ; CCW side of bass pot. R4 R N002 10k ; Bass shelving C1 N002 N001 .056uf ; Bass corner frequency. R5 C N003 100k ; Pot load limiter. * Midrange branch. R6N004 L 10k ; Boost limit. R7 N006 N004 {MPp*(2-Pv)+Pv-1} ; CW side of midrange pot. Pv = pot value, MPp = midrange pot position. R8 N005 N006 {MPp*(Pv-2)+1} ; CCW side of midrange pot. R9 R N005 10k ; Cut limit. C2 N005 N004 1.65nf ; Upper corner. C3 N006 N007 3.4nf ; Lower corner. R10 N007 C 100k ; Pot loading limiter. * Treble branch. C4 N009 L 1nf ; Treble corner. R11 N008 N009 {TPp*(2-Pv)+Pv-1} ; CW side of treble pot. Pv = pot value, TPp = treble pot position. R12 N010 N008 {TPp*(Pv-2)+1} ; CCW side of treble pot. C5 R N010 1nf ; Trevble corner. R13 N008 C 47k ; pot loading limiter. .ends Three band response control circuit with 500 k ohm pots. Bass branch. The left side of the RCC goes through a 56 k ohm resistor to the CW end of the bass control, 500 k ohms. The CCW end goes through another 56 k ohm res to the right side of the RCC. There is a 0.01 u f cap connected from one end of the bass pot to the other. The wiper of the bass pot goes through a 510 k ohm resistor to the center of the RCC. Midrange branch. The left side of the RCC also goes through a 56 k ohm resistor to the CW end of the midrange control, 500 k ohms. The CCW end goes through another 56 k ohm res to the right side of the RCC. There is a 330 pf cap connected from one end of the midrange pot to the other. The wiper of the midrange pot goes through a 680 pf cap then a 510 k ohm resistor to the center of the R C C. Treble branch. The left side of the RCC goes through a 220 p f capacitor to the C W end of the treble control, 500 k ohm pot. The CCW end of the treble control goes to another 220 p f cap. The other end goes to the right side of the RCC. The wiper of the treble pot goes through a 240 k ohm resistor to the center of the R C C. * C:\Users\Your Name\Documents\LTspiceXVII\Audio\MM-3-B-500k.sub * Three band RCC (Response Control Circuit) with 500 k ohm pots. .subckt MM-3-B-500k L C R ; Left, Center, and Right, instead of input, grid, and output. * Bass branch. R1 N001 L 56k ; Bass shelving. R2 N002 N001 {BPp*(2-Pv)+Pv-1} ; CW side of bass pot. Pv = pot value, BPp = bass pot position. R3 N003 N002 {BPp*(Pv-2)+1} ; CCW side of bass pot. R4 R N002 56k ; Bass shelving. C1 N002 N001 0.01uf ; Bass corner frequency. R5 C N003 510k ; Pot loading limiter. * Midrange branch. R6 N004 L 56k ; Boost limit. R7 N006 N004 {MPp*(2-Pv)+Pv-1} ; CW side of midrange pot. Pv = pot value, MPp = midrange pot position. R8 N005 N006 {MPp*(Pv-2)+1} ; CCW side of midrange pot. R9 R N005 56k ; Cut limit. C2 N005 N004 330pf ; Upper corner. C3 N006 N007 680pf ; Lower corner. R10 N007 C 510k ; Pot loading limiter. * Treble branch. C4 N009 L 220pf ; Treble corner frequency. R11 N008 N009 {TPp*(2-Pv)+Pv-1} ; CW side of treble pot. Pv = pot value, TPp = treble pot position. R12 N010 N008 {TPp*(Pv-2)+1} ; CCW side of treble pot. C5 R N010 220pf ; Treble corner. R13 N008 C 240k .ends Cathode follower. The input terminal on the left connects to a 0.1 u f capacitor. The other end goes to the grid, pin 2, of a 12AU7. The plate, pin 1, connects to plus 250 volts. The cathode, pin 3, goes to a 3.9 k ohm resistor. The other end goes to a 33 k ohm resistor. The other end of that one goes to ground. The junction of the 3.9 k and 33k connects to one end of a 470 k ohm. The other end goes to the grid, pin 2, of the same tube. The cathode, pin 3, is the output. * C:\Users\Your Name\Documents\LTspiceXVII\Audio\MM-C-F.sub. * Cathode Follower. .subckt MM-C-F I P G O ; Input, Power, Ground, and Output. C1 N002 I 0.1uf ; DC blocking and AC coupling. XU1 P N002 O 12AV7A ; 1/2 of a dual triode. R1 O N003 3.9k ; Biasing resistor. R2 N003 G 33k ; Cathode load resistor. R3 N002 N003 470k ; Grid return resistor. .lib 12AV7A.sub .ends Triode with Triode operational amplifier. The input of the operational amplifier is at one end of a 0.1 u f capacitor. The other end of this capacitor goes to the grid, pin 7 of a 12AX7. Pin 7 also goes to ground through a 2.2 meg ohm resistor. The cathode, pin 8, goes to ground through the parallel combination of a 3.9 k ohm res and a 100 u f cap. The plate, pin 6, goes through a 750 k ohm resistor to plus 250 volts. The plate also goes to the grid, pin 7, of a 12AU7. The plate, pin 6, of the 12AU7, goes directly to plus 250 volts. The cathode, pin 8, goes through a 33 k ohm to ground. Pin 8 also goes through a 0.22 u f capacitor to the output. The output also goes to ground through a 3.3 Meg ohm resistor. End verbal description.
* C:\Users\Your Name\Documents\LTspiceXVII\Audio\MM-T-T-OP-AMP.sub .subckt MM-T-T-OP-AMP I P G O ; Input, Power, Ground, and Output. C1 I GRID 0.1uf ; DC block and AC coupling. R1 GRID G 2.2Meg ; Grid return. XU1 N001 GRID N003 12AX7 ; Amplifier stage. R2 N003 G 3.9k ; Cathode biasing resistor. C2 N003 G 100uf ; Cathode resistor bypass capacitor. R3 P N001 750k ; Amplifier plate load. XU2 P N001 N002 12AU7 ; Cathode follower. R4 N002 G 33k ; Cathode follower load. C3 N002 O 0.22uf ; DC block and AC coupling. R5 O G 3.3Meg ; C3 discharge. .LIB 12AX7.sub .LIB 12AU7.sub .ends Triode operational amplifier. The input of the op amp goes to one end of a 0.1 u f capacitor. The other end goes to the grid, pin 7 of a 12AX7. The grid also goes through a 2.2 meg ohm to ground. The cathode, pin 8, goes through the parallel combination of a 1.8 k ohm resistor and a 100 u f cap to ground. The plate, pin 6, goes through a 100 k ohm resistor to plus 250 volts. The plate also goes through a 0.22 u f cap to the output. The output also goes through a 3.3 meg ohm resistor to ground. * C:\Users\Your Name\Documents\LTspiceXVII\Audio\MM-T-OP-AMP.sub. * Single triode op amp. .subckt MM-T-OP-AMP I P G O ; .subckt labels this as a model. * Pin connections are set in order, Input, Plate supply, Ground, and output. C1 I GRID 0.1uf ; DC block and AC coupling. R1 GRID G 2.2Meg ; Grid return. XU1 N001 GRID N002 12AX7 ; Plate, grid, cathode, and tube number. R2 P N001 100k ; Plate load resistor. R3 N002 G 3.9k ; Cathode bias resistor. C2 N002 G 100uf ; Cathode bypass cap. C3 N001 O 0.22uf ; Output coupling and DC blocking cap. R4 O G 3.3Meg ; C3, discharge resistor. .LIB 12AX7.sub ; Locates tube model. .ends Pentode with triode operational amplifier. The input goes to one side of a 0.1 u f capacitor. The other end of the capacitor goes to the control grid of a 6 A U 6. The cathode goes to ground through the parallel combination of a 1.2 k ohm resistor and a 150 u f capacitor. The screen grid of the 6 A U 6 goes through a 680 k ohm resistor to plus 250 volts. There is a 3.3 u f capacitor connected from the screen grid to the cathode, not ground. The suppressor grid is connected to the cathode. The plate goes through a 270 k ohm resistor to plus 250 volts. The plate also goes directly to the grid of a12 A U 7 triode. The plate of this triode goes directly to plus 250 volts. The cathode goes to ground through a 33 k ohm resistor. The cathode also goes through a 0.47 u f capacitor to a point labeled out. There is a 3.3 meg ohm resistor connected between out and ground. End verbal description. * C:\Users\Your Name\Documents\LTspiceXVII\Audio\MM-P-T-OP-AMP.sub * Pentode with Triode Operational Amplifier. .subckt MM-P-T-OP-AMP I P G O ; Input, Power, Ground, and Output. C1 I GRID 0.1uf ; Input DC block and AC coupling. R1 GRID G 2.2Meg ; Grid return. XU1 N001 N002 GRID N004 6AU6 ; Pentode amplifier. R2 N004 G 1.2k ; Cathode bias resistor. C2 N004 G 150uf ; Cathode resistor bypass capacitor. R3 P N002 680k ; Screen dropping resistor. C3 N002 N004 3.3uf ; Screen bypass capacitor. R4 P N001 270k ; Plate load resistor. XU2 P N001 N003 12AV7A ; Triode cathode follower. R5 N003 G 33k ; Cathode follower load. C4 N003 O 0.22uf ; Output DC block and AC coupling. R6 O G 3.3Meg ; Output capacitor discharge resistor. .lib 6AU6.sub .lib 12AV7A.sub .ends Gain Block. The input of the amplifier goes through a 0.01 u f capacitor to the grid, pin 2, of a12 A X 7. The cathode, pin 3, goes through a 1.1 k ohm then a 5.1 k ohm resistor to ground. The junction of the two resistors goes to one end of a 470 k ohm resistor. The other end goes to the grid, pin 2. The plate, pin 1, goes through a 270 k ohm resistor to plus 250 volts. The plate also goes through a 0.022 u f capacitor to the grid, pin 7 of the other triode in the same tube. Pin 7 also goes to ground through another 470 k ohm resistor. The cathode, pin 8, goes to ground through the parallel combination of a 680 ohm resistor and a 470 u f capacitor. The plate, pin 6, goes through a 56 k ohm resistor to plus 250 volts. The plate also goes to one end of a 220 k ohm resistor. The other end goes to the cathode, pin 3 of the first triode. The plate, pin 6, also connects to one end of a 0.1 u f capacitor. The other end goes to the output. There is a 3.3 meg ohm resistor connected from output to ground. * C:\Users\Your Name\Documents\LTspiceXVII\Audio\MM-G-B.sub * Low distortion gain block with 12AX7.. .subckt MM-G-B I P G O ; Input, Power, Ground, and Output. C1 I N002 0.01uf ; DC block and AC coupling. XU1 N001 N002 N003 12AX7 ; Pins 1, 2, 3, Plate, Grid, Cathode. R1 N003 N004 1.1k ; Cathode bias resistor. R2 N004 G 5.1k ; R2 of feedback network. R3 N004 N002 470k ; Grid return. R4 N001 P 270k ; Plate load. C2 N001 N007 0.022uf ; Interstage coupling. XU2 N006 N007 N008 12AX7 ; Pins 6, 7, 8, Plate, Grid, Cathode. R5 N007 G 470k ; Grid return. R6 N008 G 680 ; Cathode bias. C3 N008 G 470uf ; Cathode bypass. R7 N006 P 56k ; Plate load. R8 N006 N003 220k ; R1 of feedback network. C4 N006 O 0.1uf ; Output coupling. R9 O G 3.3Meg ; C4 discharge. .lib 12AX7.sub .ends