Large project, speaker help needed

[pusur44017]

This might get messy, so if it does, I apologize in advance.
I am making this.
I think I have most of that setup, but unlike the person on that website, I want to add speakers to it.
The LED strips will use this.
I will use these speaker elements.
I understand I will need som kind of amplifier, but since I plan to send music to it using a chromecast audio,
I won't want individual audio control. The chromecast runs on 5v/2a.
Continuing from the circuit on the website is it possible to power the chromecast and the audio amplifier from this one PSU?
I need help finding an amplifier/IC to use (4 speaker elements @ 4 ohms 3A) when finding one please use this site as the cost is an issue.
I might wish to have some kind of switch (relay) between the lights part of the project, and the speaker part. I don't mind much how this is controlled as long as I can do it without too much fuss and it's wireless. (Seeing as the project already uses IR, you might want to use that, but if you propose a solution using this, bear in mind that I won't know how to code that in the Arduino, and therefore help in that department is much appriciated)

Feel free to ask if you need more information on the components I plan to use or other.

I think I'm using the same parts as described on the website. I also need help on some Arduino coding and made a separate post here. Please feel free to pitch in if you can!

Thank you in advance,
-pusur

 

[Audioguru]

The tiny speakers you selected will sound awful (no low frequencies) with music, even if their enclosures are fairly large. They will sound like a cheap clock radio.

There are class-D bridged amplifier circuit boards available that provide about 1.5 Watts or 3 Whats to one 4 ohm speaker, use four of them to drive four speakers. 3W at 5V is a current of 600mA plus about 100mA for wasted heat.

 

[pusur44017]

The tiny speakers you selected will sound awful (no low frequencies) with music, even if their enclosures are fairly large. They will sound like a cheap clock radio.

When you say enclosures, what does that mean? Do I have to build an airtight enclosure for this?
What I would like to do is to go with a commercial product, but my criteria are that it can be powered from what is already in there and that the cost is low. I might be able to find used speakers that I could buy, or I can look at the site I linked to see if i can find something easy. EDIT: how are these? EDIT2: and this to power it, but I still need some kind of switch to turn the speaker circuit off and some way to power the amp which runs at 12v. I will get a more powerful PSU if need be.

-pusur

 

[Audioguru]

A speaker must have a sealed or ported enclosure to prevent the sound from its rear that is out-of-phase with the sound from its front from cancelling low frequencies. The datasheet for most half-decent speakers (but there is no datasheet for that very cheap Chinese one) show a recommended enclosure.

The tiny Korean speaker in your EDIT1 is even smaller than the Chinese tiny speaker and it has no manufacturer's name (it might be made for LG Electronics for one of its small TVs) and no spec's.

The cheap Chinese amplifier in your EDIT2 has no audio spec's and will produce about 10 Whats or 7 Watts into an 8 ohm speaker per channel when powered from 12VDC.

 

[pusur44017]

(but there is no datasheet for that very cheap Chinese one).

I that they aren't top notch, but for me this becomes a compromise I have to take because if the cost is too great, nothing is going to happen at all. I realise that I cannot do this the way I want, so I am gonna go for a commercial product that I just put in. This means that I will still need help with relay, power for the chromecast and power for the product I choose.The product I wanna use will follow but I do not currently have time to find it.

-pusur

 

[Audioguru]

My son-in-law found a nice little speaker system that was cheap and it sounds pretty good. But its rechargeable battery charge does not last long very long.
I hope you find cheap little speakers that sound good and find out how to connect everything together.

 

[pusur44017]

Alright, realising my limitations cost wise has led me to getting a cheap set of computer speakers and just using a powered USB hub with a relay controlled by IR, rendering this post obsolete. I would still very much like Arduino coding help, if this is something you can assist with, please refer to the link in my opening post.

-pusur