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Please suggest any ways to improve punch or bass of the sound for the following audio amplifier using TDA2030A. The sound output of the amplifier lacks some bass. Can I use TDA2050 to improve sound quality?

I am driving a 5W 8ohms speaker.

Note: This is not a subwoofer circuit, it's a normal speaker.

I will be happy to know about some errors and improvements for the circuit.

Schematic

This is a picture of my speaker Speaker

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    \$\begingroup\$ I am driving a 5W 8ohms speaker. That doesn't tell us much. To get a real "thumping" base a 5 W rated speaker isn't much so you cannot expect much from that. In my view you need a speaker box with one (or two) woofers of at least 10 cm in diameter. For such a speaker, your TDA2030 amp is on the edge regarding power output. It can work but the low power amp could clip (saturate) and that will damage the tweeters in the loud speakers. The performance of a TDA2030 is more in line with the sound you get from most flat panel TVs, a tinny sound and little base. \$\endgroup\$ Jun 19 '20 at 8:09
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    \$\begingroup\$ Post a picture of the speaker you are driving. \$\endgroup\$
    – Andy aka
    Jun 19 '20 at 8:36
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    \$\begingroup\$ Increase C3. Work out the LF time constants of C2,C3, C7 and I think you'll see C3 is the limiting one, followed by C7 (which is already pretty large). If the speaker is just a drive unit sitting on the table, put it in a proper enclosure (e.g. Infinite Baffle of appropriate volume. Next, try a better speaker. \$\endgroup\$ Jun 19 '20 at 10:36
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    \$\begingroup\$ That's an acoustics problem not an electronics problem. Mount that drive unit in the middle of a 4 x 4 foot sheet of plywood or chipboard. That's the simplest sort of baffle that will help with the bass response. Cabinets can be smaller but mean more work. \$\endgroup\$ Jun 19 '20 at 13:01
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    \$\begingroup\$ Understanding C3 is easy. Consider the expression for the gain of a non-inverting amplifier. See why C3 reduces that gain to 1 at DC. Now see how the values of C3 and R2 determine the frequency at which gain has reduced by 3 dB. Compare with the other time constants in the amplifier. \$\endgroup\$ Jun 19 '20 at 14:43
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Sound depends on the signal content, amp, speaker , acoustic environment (=interacts with speakers) and what the listener likes.

If it happens that the amp power is high enough and the speakers are good enough for increasing the bass content of the signal you can insert a bass boost circuit. Change R1 to about 200kOhm and insert with parallel of R1 the series of another about 200kOhm resistor and a capacitor. That lifts bass 6dB with "shelving" principle. A good start for finding a good capacitor is 6,8nF.

Hopefully you can make elementary reactance calculations. Otherwise understanding this quantitatively is hopeless. Qualitatively the idea is to double the voltage gain and take it back gradually as the frequency grows.

As well you can add another 100kOhm in series with R1 and insert a capacitor in parallel with it. A good start for finding a good capacitor is 15 nF.

Nothing guarantees this kind of bass boosting is what you expect.The concept is complex and proper solution needs to know what you expect, what your signal has and what the speakers can output with power this low. I guess you must make C3 smaller to prevent sub-bass notes smudge everything after you have lifted things around 100Hz.

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  • \$\begingroup\$ I have a different circuit and speaker of 20W for the subwoofer. I just want to improve the base notes with this speaker because its output sound is high in the treble, at high volume the sound becomes inaudible because of high frequencies. \$\endgroup\$
    – Vishal J.
    Jun 19 '20 at 12:02
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The problem for the missing bass is that your speaker has no enclosure.

You can't get bass out of a speaker element sitting on a table without enclosure.

It's not an electrical problem with the circuit.

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  • \$\begingroup\$ Yes, @Brian already suggested this in the comments. \$\endgroup\$
    – Vishal J.
    Jun 20 '20 at 13:14

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