Article
Preamplifier 2012 (2)
Part 2: Moving-Coil / Moving-Magnet (MC / MM) board
Just in case you didn’t know, vinyl records are making a comeback and there are even under-25 musicians releasing new material on CD cheerfully along with vinyl, preferably of the 180-gram variety. Also, high-end turntables are available at extragalactic prices but none of this makes any sense if you do not have a preamplifier to match your MC or MD cartridge optimally and that’s exactly what the present design does — rather successfully.
Materials
Extra info / Update
MM/MC Board Performance
Test conditions: supply voltage ±17.6 V, B = 80 kHz; measured at Volume/Balance/Tone control board output (# 110650-1); volume set to 1 V out.
Test equipment: Audio Precision Two Cascade Plus 2722 Dual Domain (@Elektor Labs)
MD: 5 mV in, 1 kHz, JP1/2 = 15 dB THD+N 0.008 %
(source 750 Ohm) S/N 82 dB
S/N 86 dBA
S/N (input shorted) 88 dBA
MC: 0.2 mV in, 1 kHz, JP1/2 =15 dB THD+N 0.016 %
(source 1 Ohm) S/N 76 dB
S/N 79.5 dBA
Low roll-off (–3 dB) 19.8 Hz (L)
20 Hz (R)
23.3 Hz (L, IEC Amendment on)
24.8 Hz (R, IEC Amendment on)
MC stage gain 29.8 dB
Gain definitions on JP1/JP2 (dB) L R
0 0 0
5 5.22 5.23
10 10.95 10.97
15 14.71 14.72
20 19.52 19.51
Deviation from straight line:–0.06 dB (100 Hz to 20 kHz)
Component list
Resistors
(1% tolerance, metal film, 0.25W)
R1,R13,R49,R61 = optional, see text
R2,R8,R50,R56 = 100Ohm
R3,R24,R35,R51,R72,R83 = 10kOhm
R4,R52 = 56kOhm
R5,R53 = 2.2kOhm
R6,R54 = 330Ohm
R7,R55 = 3.3Ohm
R9,R38,R57,R86 = 470Ohm
R10,R11,R58,R59 = 2.2MOhm
R12,R32,R60,R80 = 220kOhm
R14,R62 = 510kOhm
R15,R63 = 430kOhm
R16,R64 = 1MOhm
R17,R65 = 27kOhm
R18,R66 = 39kOhm
R19,R20,R26,R67,R68,R74 = 2.00kOhm
R21,R45,R69,R93,R97,R98 = 220Ohm
R22,R70 = 110kOhm
R23,R71 = 150kOhm
R25,R73 = 11kOhm
R27,R75 = 2.4kOhm
R28,R29,R76,R77 = 36kOhm
R30,R78 = 180kOhm
R31,R79 = 120kOhm
R33,R81 = 43kOhm
R34,R46,R82,R94 = 68kOhm
R36,R84 = 820Ohm
R37,R85 = 1.3kOhm
R39,R87 = 750Ohm
R40,R88 = 300Ohm
R41,R42,R43,R89,R90,R91 = 160Ohm
R44,R92 = 200Ohm
R47,R48,R95,R96 = 47Ohm
R99,R100 = 100kOhm
Capacitors
C1,C8,C28,C35 = optional, see text
C2,C4,C7,C12,C27,C29,C31,C34,C39,C54 = 220µF 35V, 20%, diam. 8mm, lead spacing 3.5mm
C3,C9,C30,C36 = 100pF 630V, 1%, polystyrene, axial
C5,C32 = 15pF ±1pF 160V, polystyrene, axial
C6,C33 = 470nF 100V, 10%
C10,C37 = 22µF 35V, 20%, diam. 6.3mm, lead spacing 2.5mm
C11,C38 = 4.7pF ±0.25pF 100V, lead spacing 5mm
C13-C17,C40-C44 = 10nF 63V, 1%, polystyrene, axial
C18,C19,C20,C45,C46,C47 = 4.7nF 160V, 1%, polystyrene, axial
C21,C48 = 220pF 630V, 1%, polystyrene, axial
C22,C49 = 2.2nF 160V, 1%, polystyrene, axial
C23,C24,C25,C50,C51,C52 = 220nF 250V, 5%, polypropylene, lead spacing 10mm
C26,C53 = 1000µF 35V, 20%, diam. 13mm, lead spacing 5mm
C55-C62 = 100nF 100V, 10%, lead spacing 7.5mm
C63,C64 = 220nF 100 V, 10 %, lead spacing 7.5 mm
C65,C66 = 100µF 25V, 20%, diam. 6.3mm, lead spacing 2.5mm
Semiconductors
T1-T8 = 2SA1085, Hitachi, e.g. Reichelt.de # SA 1085; RS Components # 197-9834
IC1,IC4,IC6 = NE5532, e.g. ON Semiconductor type NE5532ANG
IC2 = TL072
IC3,IC5 = NE5534, e.g. ON Semiconductor type NE5534ANG
IC7,IC8 = LM4562, e.g. National Semiconductor type LM4562NA/NOPB
Miscellaneous
K1,K2 = 4-pin straight pinheader, pitch 0.1’’ (2.54mm)
Socket headers for K1,K2
K3 = 3-pin straight pinheader, pitch 0.1’’ (2.54mm)
Socket header for K3
K4-K7,JP3 = 2-pin straight pinheader, pitch 0.1’’ (2.54mm)
Socket header for K4-K7
Jumper for JP1,JP2,JP3
JP1,JP2 = 10-pin (2x5) pinheader, pitch 0.1’’ (2.54mm)
K8 = 3-pin screw terminal block, lead pitch 5mm
RE1,RE2 = relay, DPDT, 12V/960Ohm, 230V/3A, PCB mount, TE Connectivity/Axicom type V23105-A5003-A201
PCB # 110650-2 (www.elektorpcbservice.com)
Note: parts available from Farnell (but not exclusively), except T1–T8 and PCB 110650-2.
(1% tolerance, metal film, 0.25W)
R1,R13,R49,R61 = optional, see text
R2,R8,R50,R56 = 100Ohm
R3,R24,R35,R51,R72,R83 = 10kOhm
R4,R52 = 56kOhm
R5,R53 = 2.2kOhm
R6,R54 = 330Ohm
R7,R55 = 3.3Ohm
R9,R38,R57,R86 = 470Ohm
R10,R11,R58,R59 = 2.2MOhm
R12,R32,R60,R80 = 220kOhm
R14,R62 = 510kOhm
R15,R63 = 430kOhm
R16,R64 = 1MOhm
R17,R65 = 27kOhm
R18,R66 = 39kOhm
R19,R20,R26,R67,R68,R74 = 2.00kOhm
R21,R45,R69,R93,R97,R98 = 220Ohm
R22,R70 = 110kOhm
R23,R71 = 150kOhm
R25,R73 = 11kOhm
R27,R75 = 2.4kOhm
R28,R29,R76,R77 = 36kOhm
R30,R78 = 180kOhm
R31,R79 = 120kOhm
R33,R81 = 43kOhm
R34,R46,R82,R94 = 68kOhm
R36,R84 = 820Ohm
R37,R85 = 1.3kOhm
R39,R87 = 750Ohm
R40,R88 = 300Ohm
R41,R42,R43,R89,R90,R91 = 160Ohm
R44,R92 = 200Ohm
R47,R48,R95,R96 = 47Ohm
R99,R100 = 100kOhm
Capacitors
C1,C8,C28,C35 = optional, see text
C2,C4,C7,C12,C27,C29,C31,C34,C39,C54 = 220µF 35V, 20%, diam. 8mm, lead spacing 3.5mm
C3,C9,C30,C36 = 100pF 630V, 1%, polystyrene, axial
C5,C32 = 15pF ±1pF 160V, polystyrene, axial
C6,C33 = 470nF 100V, 10%
C10,C37 = 22µF 35V, 20%, diam. 6.3mm, lead spacing 2.5mm
C11,C38 = 4.7pF ±0.25pF 100V, lead spacing 5mm
C13-C17,C40-C44 = 10nF 63V, 1%, polystyrene, axial
C18,C19,C20,C45,C46,C47 = 4.7nF 160V, 1%, polystyrene, axial
C21,C48 = 220pF 630V, 1%, polystyrene, axial
C22,C49 = 2.2nF 160V, 1%, polystyrene, axial
C23,C24,C25,C50,C51,C52 = 220nF 250V, 5%, polypropylene, lead spacing 10mm
C26,C53 = 1000µF 35V, 20%, diam. 13mm, lead spacing 5mm
C55-C62 = 100nF 100V, 10%, lead spacing 7.5mm
C63,C64 = 220nF 100 V, 10 %, lead spacing 7.5 mm
C65,C66 = 100µF 25V, 20%, diam. 6.3mm, lead spacing 2.5mm
Semiconductors
T1-T8 = 2SA1085, Hitachi, e.g. Reichelt.de # SA 1085; RS Components # 197-9834
IC1,IC4,IC6 = NE5532, e.g. ON Semiconductor type NE5532ANG
IC2 = TL072
IC3,IC5 = NE5534, e.g. ON Semiconductor type NE5534ANG
IC7,IC8 = LM4562, e.g. National Semiconductor type LM4562NA/NOPB
Miscellaneous
K1,K2 = 4-pin straight pinheader, pitch 0.1’’ (2.54mm)
Socket headers for K1,K2
K3 = 3-pin straight pinheader, pitch 0.1’’ (2.54mm)
Socket header for K3
K4-K7,JP3 = 2-pin straight pinheader, pitch 0.1’’ (2.54mm)
Socket header for K4-K7
Jumper for JP1,JP2,JP3
JP1,JP2 = 10-pin (2x5) pinheader, pitch 0.1’’ (2.54mm)
K8 = 3-pin screw terminal block, lead pitch 5mm
RE1,RE2 = relay, DPDT, 12V/960Ohm, 230V/3A, PCB mount, TE Connectivity/Axicom type V23105-A5003-A201
PCB # 110650-2 (www.elektorpcbservice.com)
Note: parts available from Farnell (but not exclusively), except T1–T8 and PCB 110650-2.
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