My hacked together audio system using very random stuff outperforms my Logitech Z-623 in some apects

First, sorry for the audio quality - for video recording I'm using my smartphone which not picks up loud and/or deep sounds properly, because of the quality of the integrated microphones. It is a direct non-edited upload to prove that I changed nothing sound-wise of the original recording, and also I switched on/off the audio systems (plugged in sub) on camera to prove that I changed nothing on PC's sound and EQ settings, or audio systems vomume/gain settings, etc...

Btw: I adjusted the gain on the hacked together system's amp, after this I adjusted a PC volume level on which this system just not distorts highly, as last I adjusted a volume-, then bass level on the Logitech Z-623 on which similarly just not distorts highly. EQ and sound settings I showed in this video: https://youtu.be/0ffX6BQVa5o .

My Hacked together audio system's components:
- old bookshelf speaker I repaired, details here - https://youtu.be/0ffX6BQVa5o ,
- a sub made by me using old home-hifi bass speakers, details here - https://youtu.be/D0U_F2DX6rw ,
- an old PC power supply which puts out 20 Amperes on 12 Volts
- an older 2 channel Sony Xplod XM-222MK2 car amp,
- a Rockwood CR201 passive crossover for subwoofers,
- and of course random wires connectors and other misc. stuff/parts I found at home.

The other thing, I'm sorry for the fact, how I "installed" connectors on the wires: when I wired this system together, the transformer in my soldering machine broked, now I have new, but I didn't repaired yet the connections for a simple reason: it's still working fine.

The amp in the hacked together system is wired in bridged mode: the bookshelf speaker is wired in parallel with the sub - the only thing is that the crossover the bookshelf speaker's crossover is inside the speaker's enclosure (the 2 screws next to the tweeter on the right side), and the sub's crossover not. The bookshelf speaker's impedance is 8 Ohms, the sub's impedance is 2x4 Ohms wired in series to 8 Ohms, so, if the sub is wired in parallel with the bookshelf speaker, it makes 4 Ohms impedance load on amp. I know that the amp with that power supply can put out approx. 80 WRMS for 4 Ohms, but the crossovers have some "+" resistance, so, the amp maybe puts out just only 70 or 70something WRMS power. So, it is pretty interesting that a hacked together system like this with approx 35-40 percent of WRMS power of a Logitech Z-623 is as good as, or in some aspects better like a Logitech Z-623 - at least in my room, and at least on that or similar music what I've used in the video.

Sound comparison:
- sound range which the systems can play - especially in my room - is the same for both audio systems,
- deep bass is a tiny bit louder on Logitech Z-623,
- higher bass and kicks are definetly louder on the hacked together system,
- mids are louder and somewhat more detailed on the hacked together system,
- highs / trebles are louder on hacked together system, but Logitech Z-623 playes very tiny bit higher,
- Logitech Z-623 is somewhat more "boomy" / have somewhat less accurate sounding like the hacked together system - it is not a big difference, but definetly hearable,

So, the Logitech Z-623 wins in deep bass's loudness, and in higher top frequency of highs / trebles, in other aspects the hacked together system wins.

The music I used: Chris Later & Dany Yeager - There's Nobody Else [NCS Release] - https://youtu.be/3hXbjp-FcTc from NoCopyrightSounds YouTube channel - https://www.youtube.com/channel/UC_aEa8K-EOJ3D6gOs7HcyNg . I not edited this music, just opened it in Audacity, selected a part, and loop-played it to be able to do the camera what I've done.

Video parts:
0:00 - Showing the systems and volume settings
0:42 - Bookshelf speaker sound
1:19 - Hacked together system sound
1:57 - Logitech Z-623 with port extension sound
2:37 - Logitech Z-623 without port extension sound
3:21 - Hacked together system sound
3:40 - Putting back the port extension + hacked together system sound
4:05 - Logitech Z-623 with port extension sound
4:33 - Hacked together system sound

Thanks for watching