Pill box preamplifier! (ΤL072)

This is schematic of the circuit based on this one .I've used a TL072 op amp instead.This is modified for single supply.

And here is the schematic for dual supply.

Explanation of the circuit

gain
Gain is set  by two resistors R4/R1.In the image above gain is 4.7K/1K=4.7 which is translated as 12db in decibels.In the image below gain is 100k/1k=100

voltage divider

This arrangement is for a single power supply.The two 47K  resistors and the .1uF capacitor is a voltage divider.

high-pass cut off
The 10uf and the 1k resistor at the input of the preamp (pin 2) set the high-pass cut-off frequency.In plain words -in this circuit-smaller capacitor less bass.Bigger capacitor more bass.


I've housed my preamp in this tin case box!This helps avoid  various noises.

I'm using 5volts to power the preamp here.More volts give out more power.



variable gain

You can use a variable resistor in place of R4 for variable gain.

This preamp is outputting to a TDA7360 amplifier bridge amplifier (22 watts)  an older project of mine.


Pcb layout
To make things easy here is the pcb layout for this preamplifier.

Here is the preamp with switch,led light and knob added.



In the video below I'm using this preamp with an another project of mine a TDA7360 amplifier.




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