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instead of using a radio, I want to install a Raspberry Pi 3 with my own features in the 2Din Slot, so I have to make my own circuit to play audio. I tried with the following modules based in LM386 pic:

It doesn't work bad at all, but neither good enough, the max volume is not as high as I would like it to be, the sound is not clear, starts to crackle if I increase it, and the bass level is so bad.

Should I try with my own LM386 circuit where I select my own resistor and capacitors till I get the sound I want? should I look for another circuit? another device? maybe something like an equalizer? I would like it to be small enough and as customizable as possible. Also, high bass is one of my priorities.

Voltage is 12.6v Speakers resistance is 4ohms

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    \$\begingroup\$ Have you looked at the datasheet of LM386? Look the "Distortion vs Output Power" graph. See how the curve dramatically raises from 0.2Watts? LM386 is totally unsuitable for this usage. \$\endgroup\$ – dim Dec 9 '16 at 14:57
  • \$\begingroup\$ uh :/ so what pic should I look for? \$\endgroup\$ – Mc Kernel Dec 9 '16 at 15:10
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    \$\begingroup\$ "pic"? What does that mean? Picture? Anyway, it seems you prefer premade modules. Look for some class-D amp modules that advertise 2x 20 watts or something like that. There are tons of those on the internet. Note that you could use a class AB amp (or make one yourself), but I'm afraid the cooling will become a problem in the car DIN slot. \$\endgroup\$ – dim Dec 9 '16 at 15:16
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    \$\begingroup\$ LM386 is not programmable. No, please, use the right terms. You just meant "IC". And in full-capitals, it's better, since we can then understand it's an acronym (yes, I can be worse than Goebbels sometimes). \$\endgroup\$ – dim Dec 9 '16 at 15:41
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    \$\begingroup\$ Last advice: given the bad things that can happen on the battery voltage, you'd likely want to put some protection \$\endgroup\$ – dim Dec 9 '16 at 16:26
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LM386 power amplifiers are just too puny to overcome high ambient noise level inside a car. The cracking you describe could have two causes: power amplifier clipping, or speaker overload. Considering the weak driver (LM386), amplifier clipping likely causes distortion, and limits power output.
You certainly need a more powerful amplifier. Some considerations for you before choosing a solution:
What net speaker resistance will the amplifier drive? (8 ohms? 4 ohms?...)
From what DC voltage source will the amplifier be powered? (12.6v? custom?)

Your open-ended sound-level spec ("not as high as I would like it to be", "high bass is one of my priorities") is too subjective. It is possible that a bridged amplifier powered from the 12.6v car source will satisfy, if it drives a 4-ohm speaker load.
Bridged one-channel amplifier At maximum volume (where clipping begins), conversation with an adjacent companion will be very difficult. If you need more volume, a higher DC supply voltage than 12.6v would be required. I am assuming old-school Class AB linear amplifier technology, similar to the low-power LM386.

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  • \$\begingroup\$ I updated my question, 12.6v and 8ohms (I guess) \$\endgroup\$ – Mc Kernel Dec 9 '16 at 15:54
  • \$\begingroup\$ Hm, I'm looking for that TDA2005M, I got some doubts... do I need one IC per channel (L and R), right? so I connect R output with both rear and front R in series? At least thats how I did with the module shown in my picture. Well, by now I will look for the datasheet. \$\endgroup\$ – Mc Kernel Dec 9 '16 at 15:56
  • \$\begingroup\$ @McKernel , Yes, one IC for LEFT, another IC for RIGHT. I would connect Rfront & Rrear in parallel, not series. (Lfront parallel Lrear). Be careful to phase properly for good bass. Consider too, dim suggestion of Class D bridged amps for their better efficiency, less heatsinking required. You'll need considerable heatsink for those two TDA2005's. \$\endgroup\$ – glen_geek Dec 9 '16 at 16:15
  • \$\begingroup\$ Alright, at first I tried in parallel, but for some reason it didn't gave me any good result at all, I tried in series and worked much better :/ \$\endgroup\$ – Mc Kernel Dec 9 '16 at 16:22
  • \$\begingroup\$ @McKernel , speakers parallel with LM386? Those can't put out enough current into parallel speakers. Lots of current drive should allow parallel speakers to sound loud. \$\endgroup\$ – glen_geek Dec 9 '16 at 17:11

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