# How to reduce distortion in amp with Tda2030 IC when using at high volume

This is my circuit diagram.

And also how to gain bass and clarity

• Hey, Can you please explain more about what you are trying to do and what specific problem you have? – Niteesh Shanbog Apr 23 at 5:29
• I made this amp with tda2030 ic,input power is 9 volt,I am using phone as input audio,when I increase volume from phone ,the sound gets distorted at full volume,the sound not gets distorted,when the sound is at 70 percent ,slightly less than full volume.how to correct the distortion,how can I achieve good quality sound in this project? – Singh Brahmjot Apr 23 at 8:00
• Please add this in the question! – Niteesh Shanbog Apr 23 at 8:36
• Are you using a 9V transistor radio battery? – JRE Apr 23 at 9:54
• I am using 9v dc travel adapter – Singh Brahmjot Apr 23 at 14:23

Benguru is right, few more comments: Using a single 9V supply is no good idea, better 12 or +-9V (no small 9V block of course). Such PA can clip in the voltage domain, then increasing the supply voltage is best. If clipping is in current domain, then maybe the impedance of LS is too small (like 2 ohms, which is in contradiction to the datasheet). For checking this an oscilloscope is best. Also check how large your supply really is directly at the IC, and under that full load conditions. To avoid oscillations, put the series RC directly at the IC output, not behind the elko C3.

First of all if you wanted to get the most out of your amplifier circuit, why didn't you tried the typical application circuit of the datasheet first? I can already see that your speaker is not wired in the same configuration, is there a reason for that?

Anyway, the volume of your amplifier will depend on a few things:

1. The amplitude of your output signal
2. The impedance of your speaker

The combination of both those parameters will give you the output power of your audio signal, thus your audio level. This follows the very basic rule, $$P=\frac{U^2}{R}$$

And you can get a rough idea of the power your amplifier circuit is going to make with a 4 and 8 Ohms load directly from the datasheet (in this case 14 and 9 W respectively)

Now this power figures are for a power supply of +-14 V, you need to understand that the amplitude at the output of your amplifier cannot go beyond your voltage rails. Overdriving your amplifier will clip your signal (note that you will still perceive an increase in volume due to the fact that the signal is slowly morphing into a trapezoid, which will increase your output power), this signal clipping is most probably what is causing distortion in your circuit.

If you want to have higher output volume, you will need to increase your supply voltage, and/or reduce your speaker impedance.

If you just want to get rid of the distortion when applying to high of an input signal, you should reduce your input level with a voltage divider (in the form of a potentiometer, as on the figure 17, is completely fine, in my book at least) to a level that does not clip.

Note that to get the maximum out of this amplifier you will need a 36 V rail to rail supply and a 4 Ohms speaker. Anything that you do that get you closer to this will help increase the output volume of your amp.

If you still want to power everything from 9 V (a battery for instance) you can look into step-up converter. But be aware the switching of those converters can be a pain to filter out, and you don't want those alongside your music. Thus usually music devices tend to use linear regulators, but it is not set in stone (most modern music equipment manage very well switching converters in musical applications, but for a DIY project this might be a hassle).

If you need a basic layout for a signle rail supply there is one in the datasheet as well,

You could very easily scale this in potoshop or inkscape, and try to brew your own old school looking pcb. You might even be able to use third-party software to convert your artwork into gerber, if you need.

• OK will try this but I am not good at reading circuit diagrams ,help me to understand it – Singh Brahmjot Apr 24 at 4:31
• What are these dotted lines with some components and what are those black rounded rectangles below c5 and c3 capacitor. From which point I need to give the supply. – Singh Brahmjot Apr 24 at 4:34
• The dotted lines represent an optional potentiometer (variable resistor) which is used as a variable potential divider, in order to control precisely the maximum amplitude of the input signal. It will feed only a ratio of what your input signal is to the amplifier, thus eliminate the clipping in presence of to high input signals. The black rounded rectangles are grounds (GND). Those idicate the reference potential. In a single supply configuration it is the lowest/most negative potential in your circuit. In a dual rail it is the middle potential between V+ and V- – benguru Apr 24 at 7:11
• Basically the circuit is a simple non inverting amplifier, with some filtering capabilities added to it. You should take care when laying out your schematic to respect some kind of flow in the layout of your comonents. Usually you want the signal going from left to right just like in figure17. This makes a lot more sense since you will be able to recognize the more popular Op-amp arrangement. – benguru Apr 24 at 7:16
• If you really want more explanation I can take the time and add another answer, since it is complicated in the comment section – benguru Apr 24 at 7:17