Most cheap amp ICs perform well when they're outputting less than a watt, with distortion barely audible. Try connecting the same amp board to your main HiFi system if you have one and do some listening tests against the original HiFi amp. Then turn it up and it's a completely different story.

As always the speakers are the crucial part and having decent speakers will make a big difference. What a DSP can do is correct bad speakers to some degree. A typical cheap computer speaker has a muddy midrange, can't reproduce past 13 kHz or so, and has little bass due to the small driver. With DSP the manufacturer would typically low pass the amp input, smooth out the nonlinear frequency response, lift the bass a bit, and apply compression and limiting to increase perceived volume and protect the system. The results are still constrained by physics but the manufacturer is in this case able to save money on the drivers and box while getting similar sound quality.

Yes, of course is not hifi. Not in any dreams, but for the price, being 2 orders of magnitude less money, impressive. Also in comparison with old little radios, much much much better.

I'm interested in which speaker and amp those were. Also, the plastic box :)

The amp: https://www.reichelt.de/de/de/shop/produkt/entwicklerboards_...

The speakers: https://www.reichelt.de/de/de/shop/produkt/breitbandlautspre...

Box: https://www.reichelt.de/de/de/shop/produkt/gehaeuse_serie_op...

Design of a friend, final product looks like this: https://hackaday.io/project/198249-untonie-antony

Not the OP, but if you have a little budget, HifiBerry's AMP2 [0] sounds great. After my dad gave his Hi-Fi stack to me (due to having no space at home), I built a small system with this and connected to a set of passive 2.1 Kenwood Hi-Fi speakers for him. They sound amazing, plus HiFiBerry OS is superb for connectivity.

I just want to note that software is built with collaboration of Bang & Olufsen. Both hardware and software oozes quality.

[0]: https://www.hifiberry.com/shop/boards/dealing-with-blocked-p...

The hifiberry documentation is a mess. Let’s say you want to get rid of your Sonos system and start at zero with a Pi (it’s not my first one)… which features could be replaced by hb? What hardware should I buy? Which licenses?

I don't have a Sonos system, but I'll try my best to run it down for you.

Platform has two starting points: Raspberry Pi + AMPs (or DACs) or Beocrate [0]

If you go with the former, you need a Raspberry Pi 4 or 5 (even 2GB models are OK), HiFiberry board of your choice, a case (available from HifBerry), and a PSU in 19-24V range.

My setup is as follows:

    - Kenwood 2.1 passive Hi-Fi speakers.
    - HifBerry AMP2
    - Raspberry Pi 4 / 2GB
    - Steel case for Raspberry Pi + Board
    - 20V Meanwell power supply with a barrel jack.

If you prefer to use your own amp or powered speakers, there are DACs which you can directly connect to line level inputs. They support the same OS, and some are even support XLR outputs or multichannel I/O for production/studio needs.

If you want go all in, you can add a DSP into the mix which allows parametric eqaualization, and room compensation with optional USB Mic (similar to how B&O speakers measure room to self-optimize). Also you can design your own DSP chains and upload to the DSP.

Regardless of the OS you run (HifBerry OS or HifiBerry OS64 (which is beta)), you get the following services out of the box:

    - Roon
    - AirPlay
    - Spotify Deamon
    - Spotify Connect
    - RadioBrowser & TuneIn support
    - Squeezelite for Logitech/Squeezebox
    - Music (for local files)
    - Bluetooth

Spotify daemons require a premium subscription and Roon needs a license/subscription.

There are also extensions, but I don't use any of them and don't know what's available.

I use the system mostly with MPD to play music from my and dad's personal collections. MPD can also connect to a Samba server.

If you have any other questions, I will try my best to answer. Hope this helps.

[0]: https://www.hifiberry.com/beocreate/

This helps a lot! Thank you very much!

It's been shown that, at least for guitar speakers, the box they're in doesn't matter at all. The entirety of the sound quality or lack thereof is in speaker itself. Of course that is only one speaker , no crossover to worry about.

That's entirely untrue, particularly at lower frequencies. This isn't audiophile cork-sniffing - the behaviour of a loudspeaker can be radically altered by the design of the enclosure. Entire textbooks have been written on the topic.

https://www.amazon.com/Introduction-Loudspeaker-Design-John-...

Guitar speakers, famously known for their low range.

Open low E is 82hz. That’s pretty low.

Jim Lill has a video on Youtube testing exactly that. It demonstrates conclusively that cabinet design for guitar speakers makes a difference:

https://www.youtube.com/watch?v=-eeC1XyZxYs

This is hardly surprising; cabinet design matters for every kind of loudspeaker. Note also that electric guitars can produce a wide range of frequencies, especially once you add distortion. Distortion generates additional tones both higher and lower in frequency than those already present.

Oh man, I've got some egg on my face for this one. I actually have a guitar cabinet that has a special geometry that disperses the sound in an area instead of directionally like guitar speakers normally do, which I bought explicitly for that purpose! Despite this, I still said what I had said, a couple posts up. How embarrassing.