Building an Electronic Piano using 555 Timer IC

In this article, I will guide you to make your own Electronic Piano using 555 timer IC and few Components like Resistor and Capacitor. An electronic Piano is a musical instrument which is used to generate different frequencies. For this purpose, I have used 555 timer IC, which has 8 pins and is used in producing delays, vibrations, oscillations, etc.

This IC generally works in three different modes that are- Astable, Bistable, and Monostable.

The IC can also be used to make NOT gate. Now here I am using 555 in astable mode.

The formula of frequency of output wave in this mode is:

F = 1.44/((R1+2R2)*C)

The piano in this project will generate seven different notes of Sargam

Sa – 240 Hz

Ra – 270 Hz

Ga – 300 Hz

Ma – 320 Hz

Pa – 360 Hz

Dha – 400 Hz

Ni – 450 Hz

To generate these frequencies, I have fixed the value of R1 as 1k

and C as 100 nF

Now we will calculate R2 for different frequencies

For Ni

F(in Hz) = 1.44/((R1+2R2)*C)

450 = 1.44/((1000 + 2R2)*100 * 10 ^ (-9))

R2 = 15.5 Kilo Ohm

Similarly;

For Dha,

R2 = 17.5 Kilo Ohm

For Pa,

R2 = 19.5 Kilo Ohm

For Pa,

R2 = 19.5 Kilo Ohm

For Pa,

R2 = 19.5 Kilo Ohm

For Re,

R2 = 25.2 Kilo Ohm

For Sa,

R2 = 29.5 Kilo Ohm

Fig. 1: Circuit Diagram of 555 IC based Electronic Piano

Resistances are added in series for lower frequencies. For example, the frequency for Ma is 320 Hz and value of R2 is 22 Kilo Ohm. As the switch of Ma is pressed, the total Resistance R2 will be the sum of resistance in the right side of Ma i.e

15.5 + 2 +2 + 2.5 = 22 Kilo Ohm

This will assist you to make a small electronic circuit at your home. Do let us know about your views or any query in the comment section below.