Super Low Noise Phono Preamp

Schematic

PCB Lay Out

Parts List :

Resistor :
R1 = 56 Kohm/1%
R2...R9 : 68 Kohm/1%
R1O...R11 : 4,7 Kohm/1%
R1O...R11 : 4,7 Kohm/1%
R12, R15 = 1,8 Kohm/1%
R13,R19 = 150 ohm/1%
R14 = 270 ohm/1%
R15 = 150 Kohm/1%
R16,R2O : Kohm/1%
R17 = 12 Kohm/1%

Capasitor :
C1 = 4,7 pF
C2,C3,C9, C10,C11,C13 = 4,7 uF/16 V, tantalum
C4,C6 = 3,3 nF/2%
C5,C7 = 10 nF/2%
C8 = 470 nF
C12,C14 = 1 pF/35 V, tantalum

Semikonduktor :
T1...T8,T17,T19 = BC 550C, BC 414C
T9...T15,T18,T20 = BC 560C, BC 416C
IC1 = 78L15
IC2 = 79L15


Specification :
input sensitivity (Output : 200 mV):                     2,5 mV/1 kHz
input impedance:                                                49 KQ/280 pF
Maximum input voltage (at 1 kHz):                     110 mV
Distortion Factor (Output 200 mV);
                                                   100 Hz:          < 0,001%
                                                   1 kHz:            < 0,001%
                                                   20 kHz:          < 0,001%
Over Load Distortion at +32 dB (output 8,4 V)
                                                   100 Hz:          < 0,016%
                                                   1 kHz:            <  0,01%
                                                   20 kHz:          <  0,01%
Deviation from the characteristic IEC:
                    C4...C7  with 5% tolerance:          < 10,55 dB
                                  with 2% tolerance:           < 10,25 dB
Frequency response
                     (C4...C7  at 5% tolerance):          0 Hz...40 kHz
                                                                         and 10,55 dB
Comparison of signal-noise                                > 86 dB