That is not necessary.
Although a Vbe multiplier would hold the bias more constant at warm up.
I may add a Vbe multi.
We will see if that is really needed.
Although a Vbe multiplier would hold the bias more constant at warm up.
I may add a Vbe multi.
We will see if that is really needed.
This is the final for PCB.
Including changes and Volume Pot.
Including changes and Volume Pot.
I put the volume pot only to show its value.
Of course you need not to put it in PCB.
Make the PCB not too small. So it will not be too crowded.
Regarding VBEmultiplier.
Those MOSFETs are Lateral MOSFET.
They have better thermal qualities.
There are numerous circuits with only one potentiometer to set the output bias.
But it remains to be seen if we need a VBE multiplier.
Anyway I have designed a circuit with VBE multiplier already.
With BD139 and BD140. They should be put at heatsink.
From the EXICON website.
This means there is no need to have source resistors.
In the PCB do not add source resistors.
Should omit those 0.1 Ohm resistors in sources of MOSFETs.
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Beauty in Simplicity. Yes!
Ask Nelson Pass.
Here is where you buy ECX10N20-S https://gb.profusion.uk/uk/ecx10n20-s
Here is where you buy ECX10P20-S https://gb.profusion.uk/uk/ecx10p20-s
You need also one transformer. See first post.
You need also a rather big heatsink.
Ask Nelson Pass.
Here is where you buy ECX10N20-S https://gb.profusion.uk/uk/ecx10n20-s
Here is where you buy ECX10P20-S https://gb.profusion.uk/uk/ecx10p20-s
You need also one transformer. See first post.
You need also a rather big heatsink.
I hope this is the final circuit of this BULLET amplifier.
Yeah I was just thinking of using it to better control the bias, but it's certainly not needed
MY simulation shows that it will be possible to get 10.4 Watt into 8 Ohm.
But you are right. It is very close.
For higher voltage supply there would be too much heat for Class A.
Transformer should be 2x24VAC for both channels. See first post on page1.
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Lineup,
Never too much heat for Class A, just use bigger heatsinks!
Never too much heat for Class A, just use bigger heatsinks!
@Vunce
With 32V and 900mA there is 29W per channel to cool down.
Either one big heatsink for 58W or two heatsinks for 29W each.
Is it possible to use BULLET amplifier for higher voltage?
Say 35 Volt and 1A bias?
Maybe one transformer 2x25VAC?
Yes, of course this is possible. All components can take 35-40 Volt and even more.
But one transformer 2x28VAC I do not recommend.
It is too much ...
With 32V and 900mA there is 29W per channel to cool down.
Either one big heatsink for 58W or two heatsinks for 29W each.
Is it possible to use BULLET amplifier for higher voltage?
Say 35 Volt and 1A bias?
Maybe one transformer 2x25VAC?
Yes, of course this is possible. All components can take 35-40 Volt and even more.
But one transformer 2x28VAC I do not recommend.
It is too much ...
Yep, the weather has cooled and time to fire up the wood pellet stove soon. It’s Class A season again! 🥳