* SPICE netlist
V1 +Vcc 0 15
V2 0 -Vcc 15
R23a N025 Vout1 {mc(10k,tol_smd)}
R23b Vout2 N025 {mc(10k,tol_smd)}
R21a N019 Vout1 {mc(120,tol_smd)}
R21b Vout2 N020 {mc(120,tol_smd)}
R22b N020 N023 {mc(0.1k,tol_pot)}
R22a N023 N019 {mc(0.9K,tol_pot)}
C22 N023 N025 {mc(47n,tol)}
C21 N020 N019 {mc(470n,tol)}
R33a N026 Vout2 {mc(10k,tol_smd)}
R33b Vout3 N026 {mc(10k,tol_smd)}
R31a N021 Vout2 {mc(150,tol_smd)}
R31b Vout3 N022 {mc(150,tol_smd)}
R32b N022 N024 {mc(0.9k,tol_pot)}
R32a N024 N021 {mc(0.1k,tol_pot)}
C32 N024 N026 {mc(5.6n,tol)}
C31 N022 N021 {mc(56n,tol)}
V4 N027 0 AC 20
R13a N013 Vin {mc(1Meg,tol_smd)}
R13b Vout1 N013 {mc(1Meg,tol_smd)}
R11a N003 Vin {mc(120,tol_smd)}
R11b Vout1 N004 {mc(120,tol_smd)}
R12b N004 N006 {mc(10k,tol_pot)}
R12a N006 N003 {mc(90k,tol_pot)}
C12 N006 N013 {mc(47n,tol)}
C11 N004 N003 {mc(470n,tol)}
XU2 0 N025 +Vcc -Vcc Vout2 LM833 ;pnba In+)In-)V+)V-)OUT
XU1 0 N013 +Vcc -Vcc Vout1 LM833 ;pnba In+)In-)V+)V-)OUT
XU3 0 N026 +Vcc -Vcc Vout3 LM833 ;pnba In+)In-)V+)V-)OUT
XU4 N012 N005 +Vcc -Vcc \Vin LM833 ;pnba In+)In-)V+)V-)OUT
XU5 Vaud N002 +Vcc -Vcc N002 LM833 ;pnba In+)In-)V+)V-)OUT
XU6 0 N010 +Vcc -Vcc N011 LM833 ;pnba In+)In-)V+)V-)OUT
R1 N010 Vaud 1k
R2 N011 N010 1k
R3 N005 N002 2k
R4 N012 N011 2k
R5 \Vin N005 1k
R6 N012 0 1k
VAudio_noise N007 0 100m
VMore_noise1 N014 0 SINE(0 10m 10Meg)
VMore_noise N001 0 SINE(0 10m 10Meg)
R7 N011 N014 1Meg
R8 N001 N002 1Meg
R9 Vaud N007 1Meg
R10 Vin N027 10
XU7 0 N008 +Vcc -Vcc Vout LM833 ;pnba In+)In-)V+)V-)OUT
R1o N008 Vout3 {mc(470,tol_smd)}
R2o Vout N008 {mc(0.9k,tol_pot)}
R11 Vout 0 30
XU14 0 N009 +Vcc -Vcc Voutx LM833 ;pnba In+)In-)V+)V-)OUT
R40 N009 Vout3 {mc(470,tol_smd)}
R41 Voutx N009 {mc(0.9k,tol_pot)}
XU8 0 N015 +Vcc -Vcc N017 LM833 ;pnba In+)In-)V+)V-)OUT
R12 N015 Vin 470
R13 Vouty N015 0.9k
XU9 0 N016 +Vcc -Vcc N018 LM833 ;pnba In+)In-)V+)V-)OUT
R14 N016 Vin 470
R15 Voutz N016 0.9k
R16 Voutz 0 1
R18 Vouty N017 0.1
R19 Voutz N018 0.1
.ac dec 100 10 1meg
.param tol=0.1
.param tol_smd=0.01
;step param run 1 18 1
.param tol_pot=0.20

* LTspice schematic (.asc)
Version 4
SHEET 1 5840 1920
WIRE -1960 -960 -2040 -960
WIRE -1960 -912 -1960 -960
WIRE -2040 -896 -2040 -960
WIRE -2040 -720 -2040 -816
WIRE -2152 -704 -2296 -704
WIRE -856 -704 -952 -704
WIRE -680 -704 -792 -704
WIRE -2296 -576 -2296 -704
WIRE -2248 -576 -2296 -576
WIRE -2152 -560 -2152 -704
WIRE -2152 -560 -2184 -560
WIRE -2040 -560 -2040 -640
WIRE -2040 -560 -2152 -560
WIRE -1976 -560 -2040 -560
WIRE -1832 -560 -1896 -560
WIRE -1768 -560 -1832 -560
WIRE -1624 -560 -1688 -560
WIRE -1048 -560 -1128 -560
WIRE -952 -560 -952 -704
WIRE -952 -560 -968 -560
WIRE -936 -560 -952 -560
WIRE -824 -560 -856 -560
WIRE -776 -560 -824 -560
WIRE -680 -560 -680 -704
WIRE -680 -560 -696 -560
WIRE -664 -560 -680 -560
WIRE -488 -560 -584 -560
WIRE -2248 -544 -2600 -544
WIRE -2776 -512 -2920 -512
WIRE -2600 -512 -2600 -544
WIRE -2600 -512 -2696 -512
WIRE 312 -512 232 -512
WIRE 488 -512 392 -512
WIRE -824 -496 -824 -560
WIRE 1288 -480 1208 -480
WIRE 1464 -480 1368 -480
WIRE -2920 -464 -2920 -512
WIRE -2392 -448 -2440 -448
WIRE -2248 -448 -2312 -448
WIRE -1832 -416 -1832 -560
WIRE -1768 -416 -1832 -416
WIRE -1624 -400 -1624 -560
WIRE -1624 -400 -1704 -400
WIRE -1544 -400 -1624 -400
WIRE -2040 -384 -2120 -384
WIRE -1976 -384 -2040 -384
WIRE -1832 -384 -1896 -384
WIRE -1768 -384 -1832 -384
WIRE -2920 -368 -2920 -384
WIRE -1128 -352 -1128 -560
WIRE -1128 -352 -1256 -352
WIRE -1048 -352 -1128 -352
WIRE -824 -352 -824 -432
WIRE -824 -352 -968 -352
WIRE -664 -352 -824 -352
WIRE -488 -352 -488 -560
WIRE -488 -352 -584 -352
WIRE 88 -352 24 -352
WIRE 232 -352 232 -512
WIRE 232 -352 168 -352
WIRE 280 -352 232 -352
WIRE -2040 -336 -2040 -384
WIRE -1832 -336 -1832 -384
WIRE 488 -336 488 -512
WIRE 488 -336 344 -336
WIRE 616 -336 488 -336
WIRE -2568 -320 -2632 -320
WIRE -2440 -320 -2440 -448
WIRE -2440 -320 -2488 -320
WIRE -2392 -320 -2440 -320
WIRE 280 -320 216 -320
WIRE 1064 -320 1000 -320
WIRE 1208 -320 1208 -480
WIRE 1208 -320 1144 -320
WIRE 1256 -320 1208 -320
WIRE -2248 -304 -2248 -448
WIRE -2248 -304 -2328 -304
WIRE -2120 -304 -2120 -384
WIRE -2120 -304 -2248 -304
WIRE 616 -304 616 -336
WIRE 1464 -304 1464 -480
WIRE 1464 -304 1320 -304
WIRE -2392 -288 -2424 -288
WIRE 1256 -288 1192 -288
WIRE 216 -272 216 -320
WIRE -2424 -256 -2424 -288
WIRE 1192 -240 1192 -288
WIRE -2040 -224 -2040 -256
WIRE -1832 -224 -1832 -256
WIRE 1992 -208 1960 -208
WIRE 2200 -208 2072 -208
WIRE -824 -192 -824 -352
WIRE -728 -192 -824 -192
WIRE 2680 -192 2648 -192
WIRE 2920 -192 2760 -192
WIRE -488 -176 -488 -352
WIRE -488 -176 -664 -176
WIRE 616 -176 616 -224
WIRE -728 -160 -936 -160
WIRE -2040 -128 -2040 -144
WIRE -936 -96 -936 -160
WIRE 1672 -64 1656 -64
WIRE 1816 -64 1672 -64
WIRE 1960 -64 1960 -208
WIRE 1960 -64 1896 -64
WIRE 1992 -64 1960 -64
WIRE 2088 -48 2056 -48
WIRE 2200 -48 2200 -208
WIRE 2200 -48 2168 -48
WIRE 2360 -48 2344 -48
WIRE 2504 -48 2360 -48
WIRE 2648 -48 2648 -192
WIRE 2648 -48 2584 -48
WIRE 2680 -48 2648 -48
WIRE 1992 -32 1960 -32
WIRE 2776 -32 2744 -32
WIRE 2920 -32 2920 -192
WIRE 2920 -32 2856 -32
WIRE 2680 -16 2648 -16
WIRE 2920 -16 2920 -32
WIRE -1928 48 -2024 48
WIRE -1752 48 -1864 48
WIRE -872 48 -968 48
WIRE -696 48 -808 48
WIRE 1960 48 1960 -32
WIRE 2648 64 2648 -16
WIRE 2920 112 2920 64
WIRE -2120 192 -2200 192
WIRE -2024 192 -2024 48
WIRE -2024 192 -2040 192
WIRE -2008 192 -2024 192
WIRE -1896 192 -1928 192
WIRE -1848 192 -1896 192
WIRE -1752 192 -1752 48
WIRE -1752 192 -1768 192
WIRE -1736 192 -1752 192
WIRE -1560 192 -1656 192
WIRE -1064 192 -1144 192
WIRE -968 192 -968 48
WIRE -968 192 -984 192
WIRE -952 192 -968 192
WIRE -840 192 -872 192
WIRE -792 192 -840 192
WIRE -696 192 -696 48
WIRE -696 192 -712 192
WIRE -680 192 -696 192
WIRE -504 192 -600 192
WIRE -1896 256 -1896 192
WIRE -840 256 -840 192
WIRE -2200 400 -2200 192
WIRE -2200 400 -2328 400
WIRE -2120 400 -2200 400
WIRE -1896 400 -1896 320
WIRE -1896 400 -2040 400
WIRE -1736 400 -1896 400
WIRE -1560 400 -1560 192
WIRE -1560 400 -1656 400
WIRE -1144 400 -1144 192
WIRE -1144 400 -1272 400
WIRE -1064 400 -1144 400
WIRE -840 400 -840 320
WIRE -840 400 -984 400
WIRE -680 400 -840 400
WIRE -504 400 -504 192
WIRE -504 400 -600 400
WIRE -1896 560 -1896 400
WIRE -1800 560 -1896 560
WIRE -840 560 -840 400
WIRE -744 560 -840 560
WIRE -1560 576 -1560 400
WIRE -1560 576 -1736 576
WIRE -504 576 -504 400
WIRE -504 576 -680 576
WIRE -1800 592 -2008 592
WIRE -744 592 -952 592
WIRE 200 624 200 576
WIRE -2008 656 -2008 592
WIRE -952 656 -952 592
WIRE -248 672 -248 656
WIRE 200 752 200 704
WIRE 344 752 200 752
WIRE -248 784 -248 752
WIRE 344 784 344 752
WIRE 200 800 200 752
WIRE -248 912 -248 864
WIRE 200 960 200 880
FLAG 344 784 0
FLAG 200 576 +Vcc
FLAG 200 960 -Vcc
FLAG -2008 656 0
FLAG -1560 400 Vout2
FLAG -2328 400 Vout1
FLAG -1768 608 -Vcc
FLAG -1768 544 +Vcc
FLAG -248 912 0
FLAG -952 656 0
FLAG -504 400 Vout3
FLAG -1272 400 Vout2
FLAG -712 608 -Vcc
FLAG -712 544 +Vcc
FLAG -936 -96 0
FLAG -488 -352 Vout1
FLAG -1256 -352 Vin
FLAG -696 -144 -Vcc
FLAG -696 -208 +Vcc
FLAG -248 656 Vin
FLAG -1736 -432 +Vcc
FLAG -1736 -368 -Vcc
FLAG -2360 -272 -Vcc
FLAG -2360 -336 +Vcc
FLAG -2216 -528 -Vcc
FLAG -2216 -592 +Vcc
FLAG -2424 -256 0
FLAG -1832 -224 0
FLAG -2600 -544 Vaud
FLAG -2632 -320 Vaud
FLAG -1544 -400 \Vin
FLAG -2920 -368 0
FLAG -1960 -912 0
FLAG -2040 -128 0
FLAG 312 -304 -Vcc
FLAG 312 -368 +Vcc
FLAG 216 -272 0
FLAG 24 -352 Vout3
FLAG 488 -336 Vout
FLAG 616 -176 0
FLAG 1288 -272 -Vcc
FLAG 1288 -336 +Vcc
FLAG 1192 -240 0
FLAG 1000 -320 Vout3
FLAG 1464 -304 Voutx
FLAG 1960 48 0
FLAG 1672 -64 Vin
FLAG 2200 -48 Vouty
FLAG 2648 64 0
FLAG 2360 -48 Vin
FLAG 2920 -32 Voutz
FLAG 2920 112 0
FLAG 2024 -16 -Vcc
FLAG 2712 0 -Vcc
FLAG 2024 -80 +Vcc
FLAG 2712 -64 +Vcc
SYMBOL voltage 200 608 R0
SYMATTR InstName V1
SYMATTR Value 15
SYMBOL voltage 200 784 R0
SYMATTR InstName V2
SYMATTR Value 15
SYMBOL res -2024 384 R90
SYMATTR InstName R23a
SYMATTR Value {mc(10k,tol_smd)}
SYMBOL res -1640 384 R90
SYMATTR InstName R23b
SYMATTR Value {mc(10k,tol_smd)}
SYMBOL res -2024 176 R90
SYMATTR InstName R21a
SYMATTR Value {mc(120,tol_smd)}
SYMBOL res -1640 176 R90
SYMATTR InstName R21b
SYMATTR Value {mc(120,tol_smd)}
SYMBOL res -1752 176 R90
SYMATTR InstName R22b
SYMATTR Value {mc(0.1k,tol_pot)}
SYMBOL res -1912 176 R90
SYMATTR InstName R22a
SYMATTR Value {mc(0.9K,tol_pot)}
SYMBOL cap -1912 256 R0
SYMATTR InstName C22
SYMATTR Value {mc(47n,tol)}
SYMBOL cap -1864 32 R90
SYMATTR InstName C21
SYMATTR Value {mc(470n,tol)}
SYMBOL res -968 384 R90
SYMATTR InstName R33a
SYMATTR Value {mc(10k,tol_smd)}
SYMBOL res -584 384 R90
SYMATTR InstName R33b
SYMATTR Value {mc(10k,tol_smd)}
SYMBOL res -968 176 R90
SYMATTR InstName R31a
SYMATTR Value {mc(150,tol_smd)}
SYMBOL res -584 176 R90
SYMATTR InstName R31b
SYMATTR Value {mc(150,tol_smd)}
SYMBOL res -696 176 R90
SYMATTR InstName R32b
SYMATTR Value {mc(0.9k,tol_pot)}
SYMBOL res -856 176 R90
SYMATTR InstName R32a
SYMATTR Value {mc(0.1k,tol_pot)}
SYMBOL cap -856 256 R0
SYMATTR InstName C32
SYMATTR Value {mc(5.6n,tol)}
SYMBOL cap -808 32 R90
SYMATTR InstName C31
SYMATTR Value {mc(56n,tol)}
SYMBOL voltage -248 768 R0
SYMATTR Value2 AC 20
SYMATTR InstName V4
SYMATTR Value ""
SYMBOL res -952 -368 R90
SYMATTR InstName R13a
SYMATTR Value {mc(1Meg,tol_smd)}
SYMBOL res -568 -368 R90
SYMATTR InstName R13b
SYMATTR Value {mc(1Meg,tol_smd)}
SYMBOL res -952 -576 R90
SYMATTR InstName R11a
SYMATTR Value {mc(120,tol_smd)}
SYMBOL res -568 -576 R90
SYMATTR InstName R11b
SYMATTR Value {mc(120,tol_smd)}
SYMBOL res -680 -576 R90
SYMATTR InstName R12b
SYMATTR Value {mc(10k,tol_pot)}
SYMBOL res -840 -576 R90
SYMATTR InstName R12a
SYMATTR Value {mc(90k,tol_pot)}
SYMBOL cap -840 -496 R0
SYMATTR InstName C12
SYMATTR Value {mc(47n,tol)}
SYMBOL cap -792 -720 R90
SYMATTR InstName C11
SYMATTR Value {mc(470n,tol)}
SYMBOL Opamps\\opamp2 -1768 512 R0
SYMATTR InstName U2
SYMATTR Value LM833
SYMBOL Opamps\\opamp2 -696 -240 R0
SYMATTR InstName U1
SYMATTR Value LM833
SYMBOL Opamps\\opamp2 -712 512 R0
SYMATTR InstName U3
SYMATTR Value LM833
SYMBOL Opamps\\opamp2 -1736 -464 R0
SYMATTR InstName U4
SYMATTR Value LM833
SYMBOL Opamps\\opamp2 -2216 -624 R0
SYMATTR InstName U5
SYMATTR Value LM833
SYMBOL Opamps\\opamp2 -2360 -368 R0
SYMATTR InstName U6
SYMATTR Value LM833
SYMBOL res -2472 -336 R90
SYMATTR InstName R1
SYMATTR Value 1k
SYMBOL res -2296 -464 R90
SYMATTR InstName R2
SYMATTR Value 1k
SYMBOL res -1880 -576 R90
SYMATTR InstName R3
SYMATTR Value 2k
SYMBOL res -1880 -400 R90
SYMATTR InstName R4
SYMATTR Value 2k
SYMBOL res -1672 -576 R90
SYMATTR InstName R5
SYMATTR Value 1k
SYMBOL res -1848 -352 R0
SYMATTR InstName R6
SYMATTR Value 1k
SYMBOL voltage -2920 -480 R0
SYMATTR InstName Audio_noise
SYMATTR Value 100m
SYMBOL voltage -2040 -240 R0
SYMATTR InstName More_noise1
SYMATTR Value SINE(0 10m 10Meg)
SYMBOL voltage -2040 -800 R180
SYMATTR InstName More_noise
SYMATTR Value SINE(0 10m 10Meg)
SYMBOL res -2056 -352 R0
SYMATTR InstName R7
SYMATTR Value 1Meg
SYMBOL res -2056 -736 R0
SYMATTR InstName R8
SYMATTR Value 1Meg
SYMBOL res -2680 -528 R90
SYMATTR InstName R9
SYMATTR Value 1Meg
SYMBOL res -264 656 R0
SYMATTR InstName R10
SYMATTR Value 10
SYMBOL Opamps\\opamp2 312 -400 R0
SYMATTR InstName U7
SYMATTR Value LM833
SYMBOL res 184 -368 R90
SYMATTR InstName R1o
SYMATTR Value {mc(470,tol_smd)}
SYMBOL res 408 -528 R90
SYMATTR InstName R2o
SYMATTR Value {mc(0.9k,tol_pot)}
SYMBOL res 600 -320 R0
SYMATTR InstName R11
SYMATTR Value 30
SYMBOL Opamps\\opamp2 1288 -368 R0
SYMATTR InstName U14
SYMATTR Value LM833
SYMBOL res 1160 -336 R90
SYMATTR InstName R40
SYMATTR Value {mc(470,tol_smd)}
SYMBOL res 1384 -496 R90
SYMATTR InstName R41
SYMATTR Value {mc(0.9k,tol_pot)}
SYMBOL Opamps\\opamp2 2024 -112 R0
SYMATTR InstName U8
SYMATTR Value LM833
SYMBOL res 1912 -80 R90
SYMATTR InstName R12
SYMATTR Value 470
SYMBOL res 2088 -224 R90
SYMATTR InstName R13
SYMATTR Value 0.9k
SYMBOL Opamps\\opamp2 2712 -96 R0
SYMATTR InstName U9
SYMATTR Value LM833
SYMBOL res 2600 -64 R90
SYMATTR InstName R14
SYMATTR Value 470
SYMBOL res 2776 -208 R90
SYMATTR InstName R15
SYMATTR Value 0.9k
SYMBOL res 2904 -32 R0
SYMATTR InstName R16
SYMATTR Value 1
SYMBOL res 2184 -64 R90
SYMATTR InstName R18
SYMATTR Value 0.1
SYMBOL res 2872 -48 R90
SYMATTR InstName R19
SYMATTR Value 0.1