Impedance matching : The left and right inputs are performed both on a 100kOhm resistor (R4 and R11) which acts as load resistance for the turntable. The value of this resistance can be lowered, but not below 47K.

Amplification and RIAA correction : Amplification and RIAA correction is provided by two amplifiers, operational, slightly better than the NE5534 and NE5532 is also known for low noise levels. Frequency Corrections follow the curve which forms depends on the value of the resistors and capacitors that are used around the op amp: R5 to R8 and C6 to C9 for the left channel (upper circuit), R12 to R15 and C12 to C15 for the right channel (bottom circuit). Amplification (gain) is defined by the voltage on the resistor value. Resistors R5 and R12 standardize the frequency response to a value slightly greater than 35KHz. Two op amp frequency compensation is not necessary, thus improving their dynamic performance (better rise time ).

The power supply must be a symmetrical + / 9V to + /-15V (max + /-18V). Local decoupling is provided by the RC network consisting of R1, C1 and C2 for the positive branch of power, and R2, C3, C4 for the negative branch.

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Impedance matching
Left and right inputs performed well on a 47kohm resistor (R2 and R7) that acts as a load resistance for the turntable.

Amplification and RIAA correction
Amplification and RIAA are provided by the NE5532 dual operational amplifier, known for low noise, and related components. There are other integrated circuits perform better than NE5532. Correction frequency following the curve whose shape depends on the value of the resistors and capacitors that are used around the op amp: R3 R5 and C2-C4 for the left channel (upper assembly), R8-R10 and C6-C8 for the right channel (the bottom of the assembly). Amplification (gain) is defined by the voltage on the resistor value.

The supply
The power supply must be symmetrical + / 9V to + /-15V (max + /-18V). Local decoupling is provided by the RC network consisting of R11, C7 and C8 positive for power lines, and R12 C9, C10 to the negative line. For this coupling to be effective, four decoupling capacitors should be placed closest to the pin of the power IC NE5532 (terminals 4 and 8).

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