DIY ST6 Single-end DC Pure Class A Power Amplifier

[vlaoo]

Ok, it's well built. Maybe I'll need one when I'm 70 and stay at home a lot. I'll have nothing to do but enjoy the sound of a 20 watt class A amp... alone. Cos this amp is not a party amp, and when you have more than 2 people talking, a normal stereo would do just fine. So... this amp is for loners. Sad.

[scericli]

That is a DIYer should do! If this is your hobby I think you will doing the same !^_^

[jh78ghbn56]

Ill bet you enjoyed soldering all that! rofl

[RandomInsano2]

That is, bar none, the most epic sounding music for a slide show I've ever seen. Your patience is truly amazing however.

[haz939]

All that for 20w?

[scericli]

@haz939 Class A amplifier character is low efficiency and huge heat ! also the schematic needs those perfect power regulator too ^_^ 

[PA3555]

@haz939 20w in A classe *-* hum i have yamaha rx-v371 x) with natural sound :3

[vlaoo]

Looks too complicated. You spend so much money and time building it and all you get at the end is some 20watts that distort slightly less than a normal amp, which is inaudible anyway.

[scericli]

@vlaoo Distortion is not for showing the good sounding ,all high end amplifier is look complicated because they main for the power apply and the accuracy schematic diagram ,it's not surplus ^_^

[guimbadriver]

wow,look the physical quality of this Pci boards very good

[extrasonic]

Wow, these must be expensive, by looking at the caps.. Great one!

[6527mjap]

doesn't look like it's 20W amp though more likely it's 200-400W amp.

But I don't know. it looks so very neat and cool. I am building one too from a kit, pre built though. I just don't want to solder the components that time and I am shitty when it comes to soldering the legs (lol) mine say's it's 800w each channel to a 8ohms speaker and 1000W for 4 ohms. I am applying 2 transformers with 8 caps rated at 6800mf or 8600mf? can't remember by 80v. my only problem is where to get a huge case for it

[scericli]

@6527mjap Hi you may search from China site here

://s8.taobao.com/search?q=%B9%­A6%B7%C5%BB%FA%CF%E4&commend=a­ll&ssid=s5-e-p1&pid=mm_1450741­6_2297358_8935934&suggest=0_5&­source=suggest

[scericli]

@scericli The site prefix you should add "xTTP" I quit the xTTP because I can't post the link on here !!

[markd514]

@6527mjap I am SURE it is not class A

800-1000 watts are exagerated power claims. Did the company say that the THD was at 10 or 20 percent at that measurement? I would take a clean, nice sounding 20 watt amp over a 200 watt ANY day.

[scericli]

@markd514 This AMP. is try to sinking heat by the whole thick case and very successful

and those power transistors operating temp. not more than 70degree C. at room temp. 28 degree C. and each transistor rate 0.65Amp.after an hour later !

[6527mjap]

it doesn't look like it's 20W amp though more likely it's 200-400W amp.

But I don't know.

[phoenix11994466]

@6527mjap Class 'A' amps are notoriously inefficient for their size, meaning very small output for such a large power supply, they also produce a lot of heat..The big advantage of Class 'A' design is their super clean sound quality, and low distortion, which can be addictive.. 20W is not a problem if you use high efficient speakers, like 95 - 105 db watts..That would give the same Sound Pressure Level, as 800W with 80 - 85 db speakers, which is what most do.. Problem is that combo sounds shit

[6527mjap]

@phoenix11994466 thanks man I appreciate how you explained it. I've been working with electronics for long time but all I know is just the basic of amplifier. I wanna know more about this things.

[phoenix11994466]

@6527mjap You're welcome..Ive been fiddling with DIY Hi Fi for decades, and built countless speaker systems...Once by pure chance, I came across the ultimate compact sub-woofer driver, ideal for computer games, home theater etc..It's small, long throw, low distortion, and has a ruler flat frequency response...Everyone's into sub-woofers, so here's the scoop..Go to 'parts express.com' then type into their search 'Tang Band W6-1139SI'...Find spec sheet, right column.. Usable up to 800 Hz..Enjoy

[6527mjap]

@phoenix11994466 I'll check that out. thanks agian.

[scericli]

@phoenix11994466 Thanks brother you do a amazing job ^_^

[scericli]

@phoenix11994466 Very good explanation ! Thanks for watching !^_^



[costellom5]

what brand are the caps?

I find a bit strange that there are no heatsinks.for a class A amp it should put out a lot of heat.i think.it looks good though ;)

[scericli]

@costellom5

Those caps use Nover E.cap and Evox caps

This amp.use the whole case for heat sink so the heat won't over 75* C.

when room temp. not over 30* C

[Gecman]

AWESOME!

[puggles1973]

It is very unfortunate that Class A power amps are only available to those with deep pockets or serious DIYers, because you have to hear them before writing them off as a waste of electricity. I have built one (a JLH) and it sounds incredible. Pure, airy, absolute clarity, a rumbling bass with incredible low level detail. You can listen for hours and hours, very involving, no listener fatigue. Yes it gets hot, you need very big heatsinks and very robust regulated power supplies.

[hilololomoa]

really good stuff.thanks you

[termenatul]

Veri nice wach over & over COOOL

[scericli]

@termenatul

Hi bro. very appreciated your comment Thanks for watching !

[iorixs]

looks like fun

[SkankyPistol]

I would personally only go for Class A in a pre-amp stage, as someone has already mentioned it is grossly inefficient you can generate 1W of heat per 1W of audio output using this topology. Hope it sounded alright though :)

[grisflyt]

Class A generates more heat than 1W per audio watt.

But the problem is not inefficient amplifiers, but inefficient speakers. Most loudspeakers today have an efficiency of less than 1%! At least the Class A is 20 times more efficient.

So get speakers with 10% efficiency or higher.

[scericli]

@grisflyt

Hi Your right! But for myself I was DIY some 60w,30w and 15w Class A amplifiers,

those amplifiers generate power much stronger than the same AB type same power.and 20W pure class A seen like a 80W class AB

Also when the critical full power will not generate more heat than small power!

and sound is mrore improved

[scericli]

@SkankyPistol

Sound is only second of the new technics Satri mode amplifier ! So Class A

amplifier is ideal for long time listening !

Thanks for watching

[TehMG]

Very nice looking amp, nice job.

Personally though I think class A is a ridiculous waste of power for extremely small gain in audio quality. But that's just my opinion.

[scericli]

@TehMG

In recently clean enviroment Class A is not the best way for audio amplifying! but as I say for best result sound amplification "Satri" mode is the best ! anyway this is my last DIY pure class A amplifier although this is also a real single end gain stage rig .

Thanks for watching

[vfelzmann]

what???????all these for 20Watts??????

[scericli]

Yes pure class A is a low effciency power amplifier!

[tamiasthechipmunk]

Very nice job. The quality looks second to none.

[scericli]

Thanks all audio-gd gear quality is all the same even those kits

[scericli]

Thanks.This album is "Three Kingdoms" from China and the song is The War Of Red Cliffs

[radlam64]

Dramatic music. 5/5