Fortissimo-100 High-End Amplifier
Fully symmetrical audio output stage and 100/190 W

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Component list
Component List
Resistors
(default: metal film, 1%, 0.6 W)
R1, R74 = 1 MΩ
R2, R4 = 390 Ω
R3, R5, R20, R23, R64, R66, R69 = 10 kΩ
R6, R67 = 1 kΩ
R7, R8, R13, R14, R60, R61 = 3.3 kΩ
R9, R15, R27, R28, R33, R34 = 120 Ω
R10, R11, R16, R17 = 68 Ω
R12, R18 = 5.6 kΩ 5%, 1 W, metal film or metal oxide, max. 5 × 12 mm
R19, R22, R48, R49, R52, R53 = 220 Ω
R21, R24 = 33 Ω
R25, R26 = 56 Ω
R29, R30, R35, R36 = 27 Ω
R31, R37 = 1 Ω
R32, R38 = 1.5 kΩ 5%, 1 W, metal film or metal oxide, max. 5 × 12 mm
R39, R40, R41, R42 = 22 Ω
R43 = 6.8 kΩ 5%, 1 W, metal film or metal oxide, max. 5 × 12 mm
R44, R47 = 680 Ω 5%, 3 W, metal film or metal oxide, max. 5.5 × 16 mm
R45, R46 = 1 kΩ 5%, 2 W, metal film or metal oxide, max. 5 × 12 mm
R50, R51, R54, R55 = 0.22 Ω 5%, 5 W, metal film, radial, pitch 9 mm, max. 5 × 14 mm, Koa BPR58CR22J
R56 = 4.7 Ω 5%, 2 W, metal film or metal oxide, max. 5 × 12 mm
R57 = 220 kΩ
R58, R59 = 2.2 MΩ
R62 = 1.2 kΩ
R63 = 270 Ω
R65, R70, R71 = 10 MΩ
R68 = 0 Ω (wire bridge)
R72 = 3.3 MΩ
R73 = 100 kΩ
R75 = 150 kΩ
R76 = 10 Ω 5%, 2 W, metal film or metal oxide, max. 5 × 12 mm
Capacitors
C1 = 4.7 µF 50 V 5%, pitch 5 / 7.5 mm, PET, max. 7.6 × 9.7 mm
C2 = 1.5 nF 100 V 5%, pitch 5 mm, max. 2.5 × 7.2mm
C3 = 10 pF ±0.5 pF 100 V, pitch 5 mm, C0G/NP0 (TDK FG28C0G2A100DNT00)
C4, C5 = 1 nF 63 V 5%, pitch 5 mm, PET, max. 2.5 x 7.2 mm
C6...C9 = 100 µF 16 V 20%, dia. 6.3 mm, preferably 105°C
C10, C11 = 220 pF 100 V 5%, pitch 5 mm, C0G/NP0, max. 2.5 × 7.2 mm
C12 = 100 pF 100 V 5%, pitch 5 mm, PP, max. 4.5 × 7.2mm
C13, C14, C18, C19, C29 = 100 nF 100 V 5%, pitch 5 mm, PET, max. 2.5 × 7.2 mm
C15...C16 = 680 µF 35 V 20%, dia. 12.5 mm, pitch 5 mm, 5000 h at 105°C (Rubycon 35ZL680MEFC12.5X20)
C17 = 100 nF 160 VDC 5%, pitch 5 mm, PP, max. 5 × 7.2 mm (Kemet R79GC3100Z340J)
C20 – C27 = 680 µF 50 V 20%, dia. 13.5 mm, pitch 5 mm, 10,000 h at 105°C (Rubycon 50ZLJ680M12.5X25)
C28 = 2.2 µF 50 V 10%, pitch 5 / 7.5 mm, PET, max. 7.6 × 9.7 mm
C30, C31 = 10 µF 63 V 20%, dia. 6.3 mm, pitch 2.5 mm, preferably 105°C
C32 = 10 nF 50 V 10%, pitch 5 mm, X7R, max. 2.5 × 7.2 mm
C33 = 1 µF 63 V 5%, pitch 5 / 7.5 mm, PET, max. 7.6 x 9.7 mm
C34 = 22 µF 35 V 20%, bipolar, dia. 8 mm, pitch 2.5 / 3.5 mm
Inductors
L1 = 1.5 mm enamelled copper wire, approx. 60 cm, 13 turns, ID 10 mm
Semiconductors
D1, D2 = Zener diode 20 V 5%, 0.4 W, DO-35 (Nexperia BZX79-C20,113)
D3 = Zener diode 33 V 5%, 1.3 W, DO-41 (Nexperia BZV85-C33,113)
D4, D5 = 1N4148, DO-35
LED1 – LED4 = LED, red, 2 × 5mm rectangular (Multicomp Pro MCL453MD)
LED5 = LED, green, 5 mm
T1, T2, T6, T7, T9, T10, T23, T26, T27 = BC546B, TO-92
T3...T5, T8, T11, T12, T24 = BC556B, TO-92
T13, T14 = KSA1381, TO-126
T15, T16 = KSC3503, TO-126
T17 = MJE15032, TO-220
T18 = MJE15033, TO-220
T19, T20 = NJL3281D, TO-264, 5-lead
T21, T22 = NJL1302D, TO-264, 5-lead
T25 = BS170, TO-92
IC1, IC2 = LM334Z, TO-92
IC3 = OPA177FP, DIP-8
Other
K1 = 3-way screw terminal, pitch 0.2" (Phoenix Contact 1729131 or MKDSN 1,5/3-5,08)
K2, K5 = 2-way screw terminal, pitch 0.2" (Phoenix Contact 1729128 or MKDSN 1,5/2-5,08)
2 × solder pin 1.3 mm for input (Ettinger 13.14.419)
6 × metal standoff, 10 mm, M3 M/F
6 × metal standoff, 30 mm, M3 M/F
K8, K9 = blade terminal, PCB mount, hole 3.3 mm, blade 6.35 × 0.81 mm (Amp/TE Connectivity 42822-2 or similar)
RE1 = relay 16 A / 250 VAC / 30 VDC (Omron G2R-1-E 48DC)
4x M3 × 8 machine screw (for standoffs at K3/K4 and blade terminals at K8/K9)
8x M3 × 12 machine screw, black (for board standoffs and T17/T18 on heat sink, TR Fastenings M312 PRSTMCB100-)
4 × M3×16 machine screw, black (for T19/T20/T21/T22 on heat sink, Toolcraft 839672)
18 × M3 nut
8 × M3 washer, plain, steel
HS1, HS2 = heat sink, 9 K/W, length 50.8 mm (Fischer Elektronik SK 104 50.8 ST)
Heat sink, 0.6 K/W, 100 × 180 × 48 mm (Fischer Elektronik SK53-100-SA)
4 × ceramic thermal interface pad for T19...T22, 23 × 20 × 2 mm (Silfox SL-012-AL20)
2 × ceramic thermal interface pad for T17/T18, 18 × 12 × 1.5 mm (Silfox SL-019-AL15)
2 × insulating bush for T17/T18, TO-220 (Fischer Elektronik IB 6)
1 × IC socket, DIP-8, for IC3
PCB 210364-1 v1.1
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