pblix,
MOSFETs are abundant, you are free to use them.
I choose to use tubes (although I am not a fan of the concertina phase splitter, whether it uses a tube, or uses a MOSFET).
Build an all MOSFET amplifier if you want to.
I have used JFETs, interstage transformers, and tubes.
I built concertina phase inverters, paraphase inverters, and CCS connected to two cathodes phase splitters (LTP phase splitters).
I prefer to use LTP phase splitters. Or my most recent amplifiers, a CD player with balanced XLR outputs, and a balanced amplifier.
All parts and circuits have tradeoffs.
We all make some tradeoffs (even if you do not design and build, you purchase an amplifier based either on amplifier topology, or amplifier sound . . . . . or both.
Carter's liver pills used to be abundant, but did you ever take any?
MOSFETs are abundant, you are free to use them.
I choose to use tubes (although I am not a fan of the concertina phase splitter, whether it uses a tube, or uses a MOSFET).
Build an all MOSFET amplifier if you want to.
I have used JFETs, interstage transformers, and tubes.
I built concertina phase inverters, paraphase inverters, and CCS connected to two cathodes phase splitters (LTP phase splitters).
I prefer to use LTP phase splitters. Or my most recent amplifiers, a CD player with balanced XLR outputs, and a balanced amplifier.
All parts and circuits have tradeoffs.
We all make some tradeoffs (even if you do not design and build, you purchase an amplifier based either on amplifier topology, or amplifier sound . . . . . or both.
Carter's liver pills used to be abundant, but did you ever take any?
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I'm going to go slightly off topic here. I have been thinking about self inverting push pull drive and it occurred it may have it's place in simple low power amplifiers.
There is an example here, see the schematic at 9 min 42 seconds into the video, sound test at 10:50.
Single ended outputs require require a magnetic bias in the output transformer core requiring a D.C. bias current and consequently a gap in the magnetic circuit to avoid core saturation, this gap reduces the inductance. A push-pull transformer does not require a magnetic bias, the D.C. currents from the push-pull windings theoretically produce zero DC (and magnetic) offset, so no inductance reducing gap is required in the magnetic circuit.
So it may be possible with a similar parts count to a SE output make a self inverting PP amplifier using a smaller cheaper output transformer while obtaining similar results.
There is an example here, see the schematic at 9 min 42 seconds into the video, sound test at 10:50.
Single ended outputs require require a magnetic bias in the output transformer core requiring a D.C. bias current and consequently a gap in the magnetic circuit to avoid core saturation, this gap reduces the inductance. A push-pull transformer does not require a magnetic bias, the D.C. currents from the push-pull windings theoretically produce zero DC (and magnetic) offset, so no inductance reducing gap is required in the magnetic circuit.
So it may be possible with a similar parts count to a SE output make a self inverting PP amplifier using a smaller cheaper output transformer while obtaining similar results.
For a guitar practice amp that 'Princeton One' looks great!
For a computer station Hi Fi Stereo, just replace the output tubes 500 Ohm cathode resistor . . .
Use a Hammond 20H 100mA choke (180 Ohms DCR) and a 330 Ohm resistor in series. That will give lower distortion and a little higher power output.
Have Fun!
For a computer station Hi Fi Stereo, just replace the output tubes 500 Ohm cathode resistor . . .
Use a Hammond 20H 100mA choke (180 Ohms DCR) and a 330 Ohm resistor in series. That will give lower distortion and a little higher power output.
Have Fun!
I get what you're saying, but I like designers who keep an open mind. The self split output is someone's failed experiment that bears no reason to be repeated, other than as a curiosity, particularly in this day and age. The tradeoffs you listed earlier for the Mosfet are simply not valid in a unity gain concertina. You should try it or at least model in in SPICE. It's quite remarkable. George Anderson (aka Tubelab) published one in the $100 challenge guitar amp thread. It could be a good start for anyone curious.
pblix,
I Do have an open mind, do you?
I like to let other designers do whatever they choose.
Their personal choice, experience, research, trying new things, etc.
I enjoy reading their posts.
I never say . . . You have to build my amplifier, it is the best.
I, as a designer, builder, and listener choose to:
Never use simulation software
Emphasize reliability, safety, simplicity, minimize mixing technology (solid state and vacuum tube in the same amplifier).
Exceptions: I use solid state rectifiers in tube amps, and sometimes use LM334 and IXYS 900, tried LM317T, single JFET CCS, single NPN CCS with an LED, etc.); and I have a tendency and preference for using circuits that might be off the beaten path.
And I never did a guitar amplifier design or build.
I always find it interesting, it seems like more guitar tube amps end up in Tubes / Valves threads, instead of ending up in Instruments & Amps threads.
The early self-inverting outputs have been proven, pooh poohed, etc. Discusion ad nausium. Instead, I built two of them (one with 6CK4 triodes)
The Tacoma Narrows bridge was a great design, until it blew up and fell down (concrete bending beyond the theoretical limits, but who noticed?).
There is a learning opportunity there.
Happy thread reading, posting, simulating, designing, building, and listening!
I Do have an open mind, do you?
I like to let other designers do whatever they choose.
Their personal choice, experience, research, trying new things, etc.
I enjoy reading their posts.
I never say . . . You have to build my amplifier, it is the best.
I, as a designer, builder, and listener choose to:
Never use simulation software
Emphasize reliability, safety, simplicity, minimize mixing technology (solid state and vacuum tube in the same amplifier).
Exceptions: I use solid state rectifiers in tube amps, and sometimes use LM334 and IXYS 900, tried LM317T, single JFET CCS, single NPN CCS with an LED, etc.); and I have a tendency and preference for using circuits that might be off the beaten path.
And I never did a guitar amplifier design or build.
I always find it interesting, it seems like more guitar tube amps end up in Tubes / Valves threads, instead of ending up in Instruments & Amps threads.
The early self-inverting outputs have been proven, pooh poohed, etc. Discusion ad nausium. Instead, I built two of them (one with 6CK4 triodes)
The Tacoma Narrows bridge was a great design, until it blew up and fell down (concrete bending beyond the theoretical limits, but who noticed?).
There is a learning opportunity there.
Happy thread reading, posting, simulating, designing, building, and listening!