Getting full 10w from this nothing!
My whole 13'x14 room vibrates, even from phone output with no preamp! yes the speaker is unique too.
But whoever comes here for a simplest class A amp with single element can imitate this.
Supply 5v 2a charger, will get more amps till I have to stop.
One thing, only 4 & 8 ohm drivers )
There's something about irf640, good power at no distortion, same scheme did not yield same with 740 or z44. Will try few more mosfets, upto 240 etc.
My whole 13'x14 room vibrates, even from phone output with no preamp! yes the speaker is unique too.
But whoever comes here for a simplest class A amp with single element can imitate this.
Supply 5v 2a charger, will get more amps till I have to stop.
One thing, only 4 & 8 ohm drivers )
There's something about irf640, good power at no distortion, same scheme did not yield same with 740 or z44. Will try few more mosfets, upto 240 etc.
Attachments
So something like this then?
Or is it a follower? Either way, very crude. Speakers do not appreciate DC very much, their power dissipation at DC is rather limited.
I would guess the secret of the IRF640 is a relatively low Vgs at the currents involved, allowing for some half-decent output swing.
And 10 W on a 5 V supply? Good joke. Try more like 0.39 / 0.78 W (8 / 4 ohm), theoretical maximum.
Or is it a follower? Either way, very crude. Speakers do not appreciate DC very much, their power dissipation at DC is rather limited.
I would guess the secret of the IRF640 is a relatively low Vgs at the currents involved, allowing for some half-decent output swing.
And 10 W on a 5 V supply? Good joke. Try more like 0.39 / 0.78 W (8 / 4 ohm), theoretical maximum.
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DID I ASK FOR ANYTHING?
'..follower..very crude..do not appreciate dc... .78w'
you don't even know this scheme at all
coz your supermarket fed theories told you to go away from natural (crude?) stuff
only to bias this to compensate that to increase those!
make some, not in simulators )) comment only then
there are places where this scheme alikes are very popular, that evolved from post tube days
without relying on cheap chip amps (of west?) and focussing on virginity (crude things?) of sound
great I did not show my own made speakers
for flat earthers, the wattage would come down from .78 then, whereas iphone 7 s inbuilt speaker is 3w ))
my room can vibrate with fraction of that, is it?
you jumbled up wattage and loudness
and did not ask for thd 'd' thing, I knew it )
handful few are truly blessed, really !
'..follower..very crude..do not appreciate dc... .78w'
you don't even know this scheme at all
coz your supermarket fed theories told you to go away from natural (crude?) stuff
only to bias this to compensate that to increase those!
make some, not in simulators )) comment only then
there are places where this scheme alikes are very popular, that evolved from post tube days
without relying on cheap chip amps (of west?) and focussing on virginity (crude things?) of sound
great I did not show my own made speakers
for flat earthers, the wattage would come down from .78 then, whereas iphone 7 s inbuilt speaker is 3w ))
my room can vibrate with fraction of that, is it?
you jumbled up wattage and loudness
and did not ask for thd 'd' thing, I knew it )
handful few are truly blessed, really !
Oh, come on,Praise ?
Praising in a creative space? With tech brains?
As impossible as astrologers ruling the world
)
Much obliged, for the less is more way of believing in addition )
Yes, more tech means more shifting from original.
There's absolutely nothing in the circuit.
Someone already posted with nicely drawn in a simulator.
That's it, the upper 8 ohm is the speaker, for me iits 4 ohm though.
Chargers are great source of CC, voice coil complements this.
Works with transistors too, with more efficiency, fets are special transistors
But, I find mosfet sounds best tubey,even balances much wider tube sound with harsh transistors so well.
Yes, more tech means more shifting from original.
There's absolutely nothing in the circuit.
Someone already posted with nicely drawn in a simulator.
That's it, the upper 8 ohm is the speaker, for me iits 4 ohm though.
Chargers are great source of CC, voice coil complements this.
Works with transistors too, with more efficiency, fets are special transistors
But, I find mosfet sounds best tubey,even balances much wider tube sound with harsh transistors so well.
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And what is the third one?
I.
10W, 5V x 2A (supply spec's)
Indr:
Simple is cool, and if you're happy with it, what else matters? -It's DIY. The best part of Do-It-Yourself is being able to do it your own way.
And if you want to analyze it or take it further, you're in good company.
Thanks ��
Yes, its diy that symbolises this forum site's importance.
Would try different mosfets, including p channel ones, pnp transistors sound quite great, so can be expected from similar mosfets.
Wish I had those rare toshibas or renesas in original, but so many veterans with good resources are here, they can try with this topology.
Just to add, I mentioned 10w as this needed smallest heat sink, so most of the i/p is transformed, you can check making thjs three component only scheme. There are talks about absolutely low efficiency of class A but I did not believe as well made class A delivers great output.
Its quite diffiult to measure exact audio o/p wattage.
Yes, its diy that symbolises this forum site's importance.
Would try different mosfets, including p channel ones, pnp transistors sound quite great, so can be expected from similar mosfets.
Wish I had those rare toshibas or renesas in original, but so many veterans with good resources are here, they can try with this topology.
Just to add, I mentioned 10w as this needed smallest heat sink, so most of the i/p is transformed, you can check making thjs three component only scheme. There are talks about absolutely low efficiency of class A but I did not believe as well made class A delivers great output.
Its quite diffiult to measure exact audio o/p wattage.
That's some lousy soldering, not to mention that is not the way to heatsink the transistor. Please refrain from BSing.
The scheme worked 62 years ago, it will work today.
Probably better with the MOSFET. Particularly since the 2N68 transistor is so low current that it can only manage a 45 Ohm load.
Note that in the 1956 scheme, the "MIC" is a carbon microphone, a resistor, which also provides Base bias much like the 4k7 in today's plan.
Probably better with the MOSFET. Particularly since the 2N68 transistor is so low current that it can only manage a 45 Ohm load.
Note that in the 1956 scheme, the "MIC" is a carbon microphone, a resistor, which also provides Base bias much like the 4k7 in today's plan.
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What are you doing here?
Others have already made this and listening, may be with some selling thoughts )
And you're after amateur solder blobs ))) in a diy space !!
Did not you see those tropical dusts gathered around?
Bad snooping
Bad gibberish too!
You've called other few ones Bs too, who liked this
Hope you never worked in marketing dept ever ))
My salutes ✊
Your reference is much more novel than mine,
Yes, after all these years )
That magazine made so many future tech souls.
I am into horns too, nature's fav shape )
Any idea about the ampere supplied by the 6v battery?
Indr. Thanks for posting your build. If you get the chance we would like to see some measurements. Please dont be too defensive to comment as that can stop constructive ones too. It looks like something I could build. I only need a few watts for tweeter duty in actively filtered speakers. So I dont know if I should lover the supply voltage. I will wait fo messurements
R1 is between 3 and 10 ohms. Assuming the speaker is 4 ohms, the circuit impedance varies between 7 and 14 ohms.
So the current taken from the battery varies between 6/7 and 6/14 amperes, say between 1.17 and 0.43 amperes.
This is class A, and assuming best situation (1.17A), the peak value is about 0.55A which is (0.55 * 0.7)^2*4 ohms = about 0.6Watt.
With a high-efficiency horn that may be enough to address a group of people.
Jan
So the current taken from the battery varies between 6/7 and 6/14 amperes, say between 1.17 and 0.43 amperes.
This is class A, and assuming best situation (1.17A), the peak value is about 0.55A which is (0.55 * 0.7)^2*4 ohms = about 0.6Watt.
With a high-efficiency horn that may be enough to address a group of people.
Jan
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