My amazing simplest classA amp with mosfet 640

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. About 0.6W theoretical max but we all know that in practice it will be less.

Jan

I hope someone will build and measure, but that it wont turn into a discussion about false claims. Its not so important now, how high is the output. when we find out it might be exactly what some builders need. - For desktop, efficient towerspeakers or tweeterduty. - with or without improvements
 
Indr you have a great idea,for speakers at 96 dB
Wol

You're the first to mention the most righteous thing 👍

advertising a 0.6W amp as 10W power is pretty much misleading. The OP clearly has no idea what he is doing, that's his business

Jan

I'm pumping clean 10w and getting good o/p with little warm heatsink, that by your words, consumes 9+ w! Which is not.
Then what would I infer? Where is the power going?
All theories, no hands on. Its in every forums.
#2 commenter allowed .78w, yours is less than that, how can theories differ?
It was not a business ad, businessman don't diy, they wait for diyers to post so to copy and improvise.
And about business, would you go after them too, who are selling 1000w pmpo stuff too?
 
do not confuse power consumption and power returned.
do not confuse power dissipated and power returned.
I like simple things like marc houston's ZCA, but that's just too simple.
a lot of people here are really, but then really competent and to learn, you have to have the wisdom to listen to those who know.
you can not come here, kick in the ant hill and complain about stings, it's you who shot in ...
 
Founder of XSA-Labs
Joined 2012
Paid Member
If you drive a MOSFET with 5v, there is about a 4v drop across the MOSFET. Your speaker is above the MOSFET, so at most it’s voltage is modulated by 1v.

RMS power from a speaker is (Vpp/2.83)^2 / R or 16mW rms. Your MOSFET is dissipating 9w? So the efficiency is 0.016/9 or 0.173%. A very low figure.

Just so you have a feel for what voltage swings across a speaker driver is required for 10wrms. A 1wrms 8ohm speaker needs 8Vpp swing or 2.83Vrms.

10Wrms requires 8.94Vrms or 25.3Vpp. You might get this if you used a 24v supply and used large 70mH inductor - like the MoFo. That amp gets 11Wrms out of a 24V PSU by the reactive component of the inductive load.

Please read the first post in this thread and you will see what a 10Wrms SE Class A amp requires. Not much, but needs 24v and a big fat inductor. Also, it has no voltage gain so to get 10Wrms out requires a Preamp that can swing 25.3Vpp.

Build This MoFo!
 
do not confuse power consumption and power returned.
do not confuse power dissipated and power returned.
I like simple things like marc houston's ZCA, but that's just too simple.
a lot of people here are really, but then really competent and to learn, you have to have the wisdom to listen to those who know.
you can not come here, kick in the ant hill and complain about stings, it's you who shot in ...


Those directive rhetoric are too cliché, we used to hear them in middle ages,
If my post was nothing, why so many competent, established and authority figures just don't pass it as another newbie hoax?
Somewhere it stings, really. What's it? Questioning establishments? Nope, not that usual thing. Its a tech area with professionals.
Simple things are for simple, by simple, of simple ones.
I'm the last one who will learn from them who are all theories.
Or did they already make?
Larger people don't care theories, they care what they get.
I too have a business, with very small and niche customers, who don't even know what a watt is.
Maybe their social hierarchical position implies to focus on the enjoyment part than wasting time after pesky details. Its all about class, really.
I don't even have to fly to deliver products as a salesman, I send detailed instructions knowing their exact need, so they can make it by anyone who's into technology.
Over the years, it was not built over hoax!
 
I have a question: What is so amazing about your amp?
You know humour :)
Well, I'm into something else at core, its about mystic beliefs, that try to bridge the real and illusion, rational and irrational. To learn the wish of nature, and spread to larger mass.
It was in vogue from ancient, reached peak during renaissance.
Ok, For this poor amp, its simple, portable, customised for specific speaker system which I designed and evolving and what I call them, singing led s (with this topology but not with this values, much like unitra made blinkers, with no additional circuitry, to me and others, its more enjoying than vertical graphic equilisers. I'm not showing stuff anymore, sorry.
All with perfect class A ambience, that literally is a continuous wave of seas, with no micro second changeover between push pull elements. Human ear is damn clever!
 
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Okay, somebody's gotta do it...
I used an IRF540 because that's what i had laying around, so it's not an exact comparison,and i used an external adjustable bias supply to find the best point, but it does illustrate the fact that with a 5 volt supply and an 8 ohm load I couldn't get more than about 4 volts peak to peak output without heaps of distortion. And that 4V p/p equals 0.25 watts output. End of story.
 

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Let it sound
Hard pass that nothing
Everything not for everyone !

Tried to reverse the polarity of the speaker? Amazing sound if the cone is displaced in or out? 6V accu? CuAg wires? :2c:

Do it, what bars you?
Real issue not the big W,
Its the schematic ;)))

Okay, somebody's gotta do it...
5 volt supply, 8 ohm...0.25 watts output. End of story.
Umm, don't think so
Three o/p values received
I know weekend chirpings.
 
So you don't agree with my actual measured results and yet you haven't measured them yourself? Would you like to explain to everybody why you have this particular point of view?

Not everybody, but who's only trying to denounce this reading all the lengthy pages.
Its a surprise how theories and practical differ that much.

7 pages and some man hours wasted after a troll, with everything put in public
Those 1000w pmpo sellers are real troll,
Keeping clean this place also implies keeping that place clean.
That's a part of society we all belong to, like here.
 
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