Are chinese diy kits any good?

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just of curiosity (not buying or making anything at the moment, but I do from time to time) I noticed that there are alot of amplifier kits on aliexpress for cheap.
For example this 2pcs 100w rms @8ohm kit for just 15eur
AIYIMA 2PCS MX50 SE 100WX2 Dual Channels Audio Power Amplifier Board HiFi Stereo Amplifiers Diy Kit-in Amplifier from Consumer Electronics on AliExpress
This got me thinking that if one is not building something costum are those kits the way to go?
I know that the quality and other factors are changing from one product to another, but lets talk in general.
If you think about it you don`t need to search from schematics, design pcb`s, source all the components that are usually hard to find in some regions of the world, etc...

This could be a perfect solution for one not aiming for superior quality and just want to make something with much less time and effort putted in, like me once I started working as a mechanic for 8 hours a day plus working on cars at home after that I really don`t have the time I had before. But that passion for building amplifiers didn`t go away because of that.

So what do you think? I want to hear your opinions.

Have a nice day
For people with limited time and maybe limited skill set, I think these kits can be very good. The amplifier you referenced appears to be an LJM design and mostly they are good designs. I bought a C4398 DAC kit based on LJM design and it is a very good kit. I did replace some of the components (mostly capacitors) with my own high quality ones, but overall I am very happy with the quality of the kit for the price that I paid, and I really enjoyed building it.

For that kind of money, you will have fun and you are very likely to end up with something that works quite well (again, for very little money).
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Mail order style electronics and audio products have always been a risky proposition, regardless of where the goods were assembled or kits of parts were packaged, the price or the brand. Brands can be a good indicator of what to expect but Chinese products are mostly unknown, constantly changing names, copying each other and all competing for the the very lowest possible price points - perhaps just for beginners and dabblers who think 'what the heck - it's cheap enough even if it doesn't work'.

Just be wary - you will get burned if you buy anything just on price and a tiny, blurry pic.
From my own experience I have the feeling that quality has not been the main concern.
I bought a set of PCB's and found multiple errors: orientation of transistors, wrong resistor values in silk screen and schematics with some of the component values and names in reverse notation. (k22 i.s.o. 22k)
From what I've read on this forum from other people is that boards can be stuffed with fake transistors and bottom end components. So I guess it really depends per board/kit. Y.m.m.v.
The kits can be hit and miss at the same time.

Friend of mine bought one because he wanted to dip his toes in after seeing what I had accomplished with diy tube, headphone, and class A amps. So he goes and buys a NAIM NAP clone with components, pcb, and instructions. No chassis or heatsinks came with it. He went with the lowest priced kit out of many, so this speaks volumes.

No instructions. Surprise!

Confused after the kit arrives, he brings it over for me to have a looksie. Components are all in one zip lock bag. I think I tossed out mearly a hand full of the components because they were too cheap or suspect (electrolytic caps were tiny), too close to the bottom or out of spec, or just not right (adjustable pot for biasing).

Replaced what I could with what I had on hand -- resistors, caps, and connectors, and left the transistors because they were labelled Sanken and I didn't have anything in terms of a replacement for those.

The pcbs were thinner than what I am used to but were probably up to the job. Not the greatest silm screening job, but whatever.

And I had to tell him he needed to order a power board, heatsinks, and a transformer. Pointed him to what looked like a trustworthy part of Aliexpress for the pcbs and to go from there.

In the end, I doubt he saved much in terms of time and money if he had just bought the bare pcbs and went to mouser or trusted sources for the proper components (I gave him the components for free). He would have saved on headache though.

I told him to finish this NAIM clone or start simple with a chip amp instead. He did just that and did a simple Chinese pcb for an LM 1875 chipamp with components from Mouser. He then tackled the NAIM clone. Both sound pretty good for what they are. He did learn that this diy thing is cheaper and nicer sounding than commercial options and you can go way overboard or not with whatever you stuff a pcb with.

So many choices and so many options.
Need to research first in order to reduce the risk of getting a bad implementation.
Then be prepared to replace most of the capacitors.

I’ve had pretty good luck, and then only buying known commodities.
Always note that the rating for max voltages will be advertised to be a wider range than is practical in reality most of the time. Same goes for wattage output, need to observe basic, established laws of physics for that.
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