 Hello everybody and welcome back to my channel So we're going to do a little power test now on this here amplifier. This is the one that I got from eBay It claims to be 180 watts Plus 180 watts or 180 watts per channel Talking to the person who sold it to me they say that's peak and it's good for 20 watts RMS per channel Okay, well, we've already looked at the datasheet and we've seen that the datasheet doesn't say it's good for 20 RMS what the datasheet says here we can look at it again. Here's it's good for two times eight watts on the output All right So let's get back to this And so I've decided because the actual chip itself the TDA chip will take maximum of 18 volts and We can put in 15 volts into the op amp. That's in there. So I'm going along with 15 volts I've switched it on so it starts warming up and We're going through this little setup because these are different. This is a bridge-tied load Which means you need differential probes for this and on my oscilloscope here Which has been my oscilloscope here, which has been camouflaged by this pack of absolutely delicious mince pies It's because the reflection It was doing my head and off the screen, but on my oscilloscope It's all like a single-ended and so I couldn't do the tests with that scope But with this little beauty I can I can take out the BNC connectors and I can use Directly connected here at a differential inputs Which means that I can measure stuff like this, which is pretty cool So we've got that set up then is there the orange and the blue on here are The two positives of the oscilloscope and then if you got a orange with a white stripe and a blue with a white stripe and they're the negatives so they're connected into this and Onto the speaker outputs And there's also another connection on the speaker output that comes out and goes around here And this is for the dummy load same thing on this side for the dummy load now We've got these yellow connections as well. You've got a yellow and This is for the You've got one yellow and one yellow stripes So this is the waveform generator channel one channel two and then we've got a common ground Which we're bringing in to this Can't use the grounds from the speakers because this is where differential and opening did Become Different this is ground here is to ensure that I've got a ground in relation to the device And these ones here are not actually grounds in relation to the device That's why it's a different setup when you're doing these things. So we've got the one ground It's connected to the grounds here I've just tied them together and then we got these two going on to these little mini grippers here Which are for the waveforms one and two Okay, and this device then just does the rest for you Which is fantastic. Yeah, can't really So what I'm gonna do now is on the oscilloscope side of things I'm gonna come over to the screen here is I'm gonna set everything running I'm gonna set my two waveform generators now I've already gone and put in there at 1.4 volts on both sides of amplitude Yeah We can adjust this I can either adjust it by its The states that it's got here, which is just a preset for me or I can do it by just clicking in there and typing in Whatever value I choose This is the waveform on both and you can see it says disable at the moment So we've not set them off running if I just move that out the way for a second I'll just put that just on the edge of this we get to see everything We get to see how different waveforms down here, but that's different We're not messing around with this at the moment like that But we've got a one kilohertz signal gonna be going in and that's exactly the same on the pair of them And we are now going to set it as to run all and as you can see it says here that it's running No on the oscilloscope side of things. We're just gonna run that and We are gonna see that we've got both traces up there and not a lot is really happening And the reason why not a lot is happening is because the volume is turned all the way down on the actual amplifier And you can see here where it's millivolts This is the AC RMS that we're going to be looking towards to do our quick calculations on how much wattage this is putting out before clipping and Down the bottom here. We've got our FFT Which is set up between 10 Hertz and 20 kilohertz We should actually bat that off to 20 kilohertz. I'm just going to talk that in there's been 20 kilohertz because it does say on the on the instruction manual which on unfortunately my cat was up here the other day and Fortunately, he didn't yack up be sick across this But he did do it on the instructions for one new piece of kit that I got that I show you maybe at another stage You might be able to see it just here And he did yeah, he was sick all over the other thing. So they got thrown Yeah, so what we're gonna do now is we're gonna start turning up the volume on this thing and seeing what it looks like as it's coming through on the On the on the on the screen over here. So there I go slowly turning it up Slowly turn it up and we'll see already if you look at the FFT When I'm when it's down here, you can see that there's some noise down the bottom I've got all this set up really for how it's going to look That's on the FFT. You can see where it's clipping Even see over there on the power supply and which power is using before and we're just to back that off into the FFT stops looking so noisy Well, you can see that that is about what you're gonna get on your full power I'm just gonna let this just warm up slightly more Just give it a half a house chance if I just feel on top of here. It's cold. That's good But it will get a lot warmer As it's running So You see we can just bring this into a little bit more if we do a hamming for this It just gives it more of a straight line on the FFT that you can see there So it might be easier for you to see when this starts distorting I'm just gonna push into distortion now just so you can see and Part distortion is when you see that these are starting to square up Okay, and as you'll see there they're square On the top of no, I just push it right to the to its fullest extent on the volume You see how they're very squared off So I'm gonna Back that off now because we don't want that screwing up and you'll see the FFT as it gets noisy a lot We just back that off now. That's nice and clean Now we can do enough take We can do enough take now our Our measurements and we're gonna see here on the measurements for the AC RMS on both channels channel one and channel two There's a slight deviation between the two channels and that can be seen any way you see channel two slightly higher Just very slightly lower but more so higher than Channel two there and so you can see it reflected here that the Channel two as the output of six point zero to one and the number just keeps moving Vaults we may as well just say six volts there And I know it's the top one is five point seven three So we may as well just say five point seven there Well, we could always round up if it makes anybody feel happier just while it's warming Let me just change and we're gonna go straight from zero I'm gonna check that is the base. Yeah straight from zero on the base I'm just gonna slowly turn that up. I'm just a little tiny bit turned up and you can see it's clipping already I just want you to see what that amplitude does And it stays up there. It's got it's clipping But you can see on the FFT look as I just move that all the way to the right And then I start backing it off backing it off backing it off You can see that that just changes on the FFT just a little bit as I back it all the way down All the way off the base. You can see the FFT cleans up I'm gonna do the same thing on the treble. It's all the way to the left at the moment So I'm gonna start very slowly just turn it to the right Probably about halfway there now as you can see the amplitude goes up and we're going into clipping anyway and You can see on the FFT You also see on the power over there now. It's using one point seven amps I just back that to one point seven twenty five point five watts and it says on our Outputs there on the C1 and C2 the ACRMS for both is seven point five volts and seven point six volts But we are you know, we're into a lot of distortion. That's probably that ten percent And if I just back that down Just get it to where we're not quite clipping there we go Turn the FFT back off slightly more volume. It's gonna let it just go a little tiny bit. There we go. Just just snug in it We've got a five point nine and six volts. We'll just call that five point nine and six We'll check that the highest number and we'll just call it Six volts if I can get it any higher that it distorting on the volume I will Just to try and snog that little extra bit over you can see the FFT is It's a little bit noisy there So let's have a look Natural but it looks like it's slightly under that so we're gonna get the five point nine and the six volts Okay, that's what we're gonna use for our measurements Let me just quickly bring up the calculator The nice easy one there so we go five point nine or six volts. Let's just choose the six volts. Yeah six square-rooted and then divided by our eight ohms Which is what our dummy loads are and we got four point five 4.5 watts RMS output. It's not even close Not even close really to what it's supposed to be able to do But this is what we got and that's not saying that the chips bad or that the data sheets bad for the chip That's in here for the TDA 570 That's all that saying is that this the setup isn't you know as good as what it could be Doing what we're doing here the way it's said to him. Well, that's fine. That's fine. It could be better, of course But it's fine. It gives us the ballpark the pretty much area of where we are But the way that this is laid out inside could probably be done better And I don't think that particular op amp in here. It's not gonna be genuine I don't know what it is four five five eight. I believe let me just have a quick little check over here And I'm pretty sure it's supposed to be a four five five eight. Yeah and I don't think it's gonna be a genuine one and even if it is It's just not It's just not a very good amp system What's the temperature like? It's warm. It's nice. I mean, it's not a radiator warmer anything like that And it is probably only the 25 maybe 26. That's that's that's pretty good Look at a bother chucking the meter on so I don't have one here and the video is getting too long anyway But there you go guys, I'll just give you an idea of what the output is really like on that There we have it. It's They say the numbers don't lie and I don't believe they do. Thanks for watching and I will catch us in the next one