 Hello everybody and welcome back to my channel. So this is the Quad 606, a kit from AliExpress. I will stick a link at the end of the video if you want to see the unbox and then the details on this. This is it built up as you can see, pretty straight forward to all the small pieces first. Don't stick these two resistors into this inductoring because as you can see there's not a lot of room and you can course yourself a bit of a pain doing it but it's slightly off on mine just because I'm not very good with it. I wanted this to be level and it would have been slightly over to the one side but anyway okay it's about that. What do you want to know? You want to know what it sounds like? I like it. I like it. It does have a bit of a richer sound. I don't know you know when I was listening to it I just thought it was like velvety. Weird you know this is me trying to explain and I don't know what the technical terms would be or you can't really put into technical terms because this is the thing the sound thing is so subjective to what I like to listen to. I liked it in a way because it seemed like at a lower volume it gave me a bit more punch on the bass. Now that's probably not very helpful to some and it could be helpful to others. I'd say that this is a great one for TV, connecting TV to because it will help get out. It just sounded like I liked it. I listened to my music. My music seemed fresh and nice and that you know I do like that sort of thing when it comes to an amplifier. Don't get me wrong I use the L12-2 and I think that's great as well. Whoever buys one of those will not be disappointed. This if you're gonna be running this you need a bigger heatsink even two of these. Is there another one here? I can get my hands on easily that is. This is you know just one of these and I've just jammed two of them together to give it more mass and but even that I mean if you're running it at not completely full belt it should be okay but they say go for 500 grams of heat-sinking and bigger. I just put this on here you can see that and that's 300 grams. So not really big enough but for what I was doing it's it's fine. See here the sound of it's okay yeah it does sound nice doesn't sound it doesn't sound dodgy at all and I was pleasantly surprised or I'm not so surprised I mean but yeah it's a pleasant enough sound. I do like it I do like it if you bought one of these when you think one of these is 10 pounds that's probably about $11 or $12 for this entire thing like this and these it's not bad at all not bad at all that's it my conclusion is yep if you I give it a thumbs up just because for me I like the sound of it with my big old speakers there you know the bass came out nice and everything sounded nice it just does sound nice so okay let's have a look at the the numbers and the test results okay so first of all this is the setup this is our transformer we got a is it's 030 030 which gives us 42 volts DC or around there once you come through the rectifier capacitor bank with our positive output a negative output and our virtual ground output that's connected into the ground here which also connects to our speaker output which will be this part of the dummy load and also to our negative on our on our probe here which is then going into the back of the sound card on the computer positive output to the side of the dummy load positive part probe and our VCC and VE there positive and negative and that's it that's that's all there this is just on there because I'll read the other channel if we were connected to another channel or not we're just doing this like this so let's just set this down look at the the screen oh mention that we are using this connected block unit for our transformer they're about to power this on now everything should be okay but you never know so let's have a little look we're gonna hit this on here and there we go let's just put this into alright so this is our noise floor that we got you see some 50 hertz in there well below the 100 low nothing to worry about a few little bits let's start putting this up alright now that's at minus 32 let's just take it to 20 because this is where this is where stack exchange audio suggests that's a good place really because you wouldn't normally be running at full board and I agree you wouldn't I certainly wouldn't and an actual factor lower listening we better so the THD we got there is 0.002829 and THD noise is 0.0094 very respectable let's go down to 10 so now this is pumping it a bit and here we've got the 0.015 0.016 for the noise included again I mean this looks like it's something that particularly doesn't it but it's not it's so low down this is like 90 dB down let me just click on the hardest peak for a moment and there we have I'm just not that back actually to that's the closest minus 89 it's very good let's see what happens when we go full board you can remember that these amplifiers were not designed for that not designed and so we are at minus 0.06 minus 2.8 that's 0.37 0.38 I'm gonna turn that off in actual fact let's just go about there again we're just gonna put that on there so you this they're not designed for it they are not designed to be run at full blast and the actual fact this is slightly over full blast from the calibration and yeah that's not how you'd be running it you'd have it a lot lower than that and I think personally if you sat between 10 and 20 that's gonna be running it pretty darn high let's go to 15 shall we 14 they'll do that's going to run it pretty high and it's still very respectable thd 0.0046 thd noise 0.075 so I'm happy with that I'm very happy with that and like I say I've already listened to this and I'm very happy with it if anything's gonna be subjective to me now it's what I read in these outputs and I've seen a lot worse than this and let's have a look at the frequency response there we go I could probably drop that down slightly just to see just to see yeah darn it so what we can actually say from now is because we could do with adding some now to this point three there so minus 3db is there so really we've got the difference here we'll take it from 1k and look at the difference there this is very sort of zoomed in normally you'd have a plus three here minus three and I can't fit around this anymore so we're just gonna measure it like this so we've got 0.74db right but we're not gonna we're just looking at as our base in the middle of our measurement and then we'll go to the hundred K here and 0.76 0.74 there let's go to 30k and if we just chuck that there this won't come in my thumbs stay still go there to the 10 we have what 7.6 here 7.4 and now here we're at 8.7 so it's not in anywhere near 1db difference on it and if we go to the 20 remember this is 0.5db this would be 1db this space is 0 to 1db and this is we're measuring between the 0.5 so it's you know it's less than a quarter of a db at 20 Hertz which is really nice that's really nice it doesn't matter after that because we're not gonna be hearing it anyway and up here you know we're doing good up there as well because it was 7.6 and we're at 7.2 there so yeah that's good that is good