Restoration signal amplifier 3000W / Restore everything in detail 

He is a Vietnamese double degree in electrical engineering and computer science, so I think he knows what he is doing.

@@Prometheus574 Replacing the caps would've been his first priority then. He would also know that that moving coil meter is useless for testing caps. They're rated at 50v so almost guaranteed they've been over volted. Why no esd precaution.

That is true. Always start with new low esr caps. And don't paint heatsinks... Heat transfer will be lower. I'm not an engineer but im building tube amps and class a transistor amps. Only use 105°C Low esr elco's. If they fail the rest will fail. You do not to be an engineer to knowing that 🤔

That is thermal paste

@@Prometheus574 So what do you know about his double degrees and all this stuff do you know him personally or are you just privy to that information

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Totally agree! It lessens the heat dissipation of the heatsinks

Ему можно, у него же спец. краска, новым алюминием обрастает :D

@@cherbet Это лак, а так надо анодировать.

🤣

perhaps peak power...

You shoud believe your eyes :) It's impossible.

И конденсаторы омметром проверяй

Not at all random. Just shortcuts. Masterful.

@@patrickburke3826 Ignorance is bliss

And it is not really wise to paint cooling blocks. These are not "painted" black but anodized to multiply the cooling area by roughing up the surface. Your paint will hinder the heat exchange now.

I wondered about that. The amp looked familiar to me. I wonder if this manufacturer is an OEM for Crown? (Google Translate: Me preguntaba sobre eso. El amplificador me resultó familiar. Me pregunto si este fabricante es un OEM para Crown.)

A gde v video remont?

@@whynot6795 это ремонт, друг. то что оне его вконце покрасил это не сильно меняет ситуацию. Вообще огонь работа.

@@Pacca33 Esli vy slepoj to da, dlja vas eto remont :D. Dlja menja eto smeshnoe video pro to kak isportit'. I znaja czto etot komik delaet dovolno xorosho vidno gde on podmenjaet usilok. Edinstvennoe chto mne interesno eto chto za xemiju ispolzuet dlja togo chtob metall bystro porzhavel.

@@whynot6795 azelit

Isopropyl alcohol is commonly used to clean circuit boards.

@@stevesmyth4982 Yeah but he uses Acetone. But Alcohol is WAY safer for plastics

Contact cleaner. But 2 types of form it is. Oily or non oily.

And you can use ethil alchol, methy alchol.. all these liquids you can use for cleaning circuits ;)

@@cihan.kurucu I use 95% Isopropyl Alcohol. It flashes off quickly leaving no residue, I usually drink the Ethyl Alcohol!!!!

The model number can be based on all kind of ratings. It's pretty common to get the biggest number which would probably be the bridged power @ 4Ohms Which could give specs per channel in the order of : 1000W/channel @ 2Ohms or 600-700W/channel @ 4Ohms or 400W/channel @ 8Ohms But the marking on the back mention 8 Ohms min in bridged mode and 4 Ohms min per channel (stereo) and there is also a 220V and something that looks like 1900W right next to it (which makes sense with 10A fuse). Let's give this amp an efficiency of 70% (which is pretty good) that gives us about 665W RMS per channel @ 4Ohms ... I'd say that it certainly hasn't more than 665W RMS per channel @ 4Ohms Nonetheless, he did a great job restoring that amp. Only at the end he was very confident to hook it up to 220V right away. I would have slowly cranked it up using a variac and see how it behaves. PS : a increment of 1B (bel) or 10dB is considered twice as loud. So you need 10 times more power to be twice as loud which would make 1000W "only" twice as loud as 100W

@@ppdan On my workbench I use a lamp in series to start the tests, then I place a heat gun in parallel with the lamp, then I connect a 6-amp breaker in parallel with the lamp, then a 25-amp breaker. This prevents damage. I noticed that he used a scrapped transistor for replacement, in the past I changed them all for new ones, in my last maintenance I did the same way, but in tests I realized that there is a difference in the drained current (which can be measured through the voltage on the resistors) and also a difference in temperature (which I managed to measure by injecting a signal before attaching it to the heatsinks), however, I'm using the amplifier like this and it still hasn't caused a problem.

He uses Acetone

I saw the same thing! I thought he was just using old isopropyl then I noticed it wasn’t evaporating, then I saw the beer bottle! 😧

@6:56

Thats what i was always told...

He also changes everything that’s not working anymore

Take our sunglasses and watch more carefully. No fake restoration LOL 😁😁😁🤣🤣

Oh yeah. But author shoud pay more attension to details. It;s easy to see that amp at the end is not painted and with dust inside.