@NanoFarad are you from India? I can see good old Keltron and BEL industrial/military grade power transistor.
Nonsense what I tell?
Excuse me!
Did my post indicate that jlh is the same amp as those from mr NP? How?
Please explain.
I have built about a dozen of working jlh amps, various versions with different outputs, different power, from 6 watts to penultimate 45 watts.
I have built almost any amp from mr NP there is, sometimes multiples of the same amp with various outputs.
You made one thread about usb.
Yet you have guts to tell me 'nonsense what i tell'. WTF!
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Nonsense what i tell?
Let's see...here is one of your posts. Its a reply to someone selling lineaum tweeters. He posted in 2007, you replied in 2021. Please read your own post. Makes perfect sense?
Attachments
in my previous post the file was not attached, now see the attachment
Attachments
on 4 pairs, I could not get enough quality even for 40 watts, I thought you did it for 45 watts ...
that's why I asked for the number of pairs...
I see. Last table on the bottom of the page demonstrates that power output increases with supply voltage.
Having two pairs or four pairs of outputs is changing current drive capability, but not power.
Unless you push the supply voltage up, no matter how many output transistors you have, you get the same wattage, except you can now drive lower resistance speakers.
Having two pairs or four pairs of outputs is changing current drive capability, but not power.
Unless you push the supply voltage up, no matter how many output transistors you have, you get the same wattage, except you can now drive lower resistance speakers.
Sorry, but these are theories.
in practice, for 45 watts at 4 ohms, an output amplitude of at least Vp=19.3 volts is required, so that the amplifier can reproduce this power without distortion, an output stage current of at least 3.5 A is needed. At the same time, in order not to overheat the transistor crystals and reduce the dependence of their amplification on temperature, it is necessary to put transistors in parallel, I believe that this is at least 7 pairs ...
so far I have not seen a 2003/2005 JLH variant with so many pairs...
wondering if someone has already done it...
of course, you can wind up the current on two pairs of output transistors, but I'm skeptical about such a solution, because I don't think this is correct...
in practice, for 45 watts at 4 ohms, an output amplitude of at least Vp=19.3 volts is required, so that the amplifier can reproduce this power without distortion, an output stage current of at least 3.5 A is needed. At the same time, in order not to overheat the transistor crystals and reduce the dependence of their amplification on temperature, it is necessary to put transistors in parallel, I believe that this is at least 7 pairs ...
so far I have not seen a 2003/2005 JLH variant with so many pairs...
wondering if someone has already done it...
of course, you can wind up the current on two pairs of output transistors, but I'm skeptical about such a solution, because I don't think this is correct...
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Are you sure?
I am listening to AlphaNirvana, AN39, which is 39 watts of classA, with just one pair of mosfets. +/-23 power supply.
Great design by Hugh and X. Lots of threads about it.
3.5A through one pair of outputs is manageable, if you have enough heatsink and forced air.
There are many threads about tiny lu jfet, an smd part, running 3A.
https://www.diyaudio.com/community/threads/alpha-nirvana-39w-8ohm-class-a-amp.344540/
https://www.diyaudio.com/community/threads/lufo-amp-39w-se-class-a-from-28v-rail.372679/
I am listening to AlphaNirvana, AN39, which is 39 watts of classA, with just one pair of mosfets. +/-23 power supply.
Great design by Hugh and X. Lots of threads about it.
3.5A through one pair of outputs is manageable, if you have enough heatsink and forced air.
There are many threads about tiny lu jfet, an smd part, running 3A.
https://www.diyaudio.com/community/threads/alpha-nirvana-39w-8ohm-class-a-amp.344540/
https://www.diyaudio.com/community/threads/lufo-amp-39w-se-class-a-from-28v-rail.372679/
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what does sure mean?
you give as an example mosfets, in which the parameters are not critical to the heating of the crystal, even with convection cooling. For bipolar transistors, everything is completely different. It's strange that this needs to be explained...
you give as an example mosfets, in which the parameters are not critical to the heating of the crystal, even with convection cooling. For bipolar transistors, everything is completely different. It's strange that this needs to be explained...
'Sure' means that someone on the page that i linked already measured 45 watts out of jlh amp with two pairs of outputs.
You are saying its impossible.
So authors of that page are wrong, or you.
This needs to be explained.
You are saying its impossible.
So authors of that page are wrong, or you.
This needs to be explained.
Can,t you not hear the different between v-fet,mosfet and transistor,A Linsly Hood is musical,and np is analitical.
Rudi van Stratum have in years ,80,90 different schematic,s make of Linsly Hood Amplifier .
Then Lineaum,i have A question of lineaum of you can four of eight high lineaum lx 5 make A speaker on 200 hz,what is the problem 😀😀.