Balle Clorin
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- Dec 26, 2017
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Take a look at this.. Makes me wonder if not the buyers are mislead by the selling arguments...at a quite high price.
Do they understand what they are getting? Not a Single ended 300B triode, but a push-pull amplifier consisting of a Mosfet and 300B triode in combination..
Would they buy it then?
WE:
And the evaluation of the patented circuit here by TubeCad.
Patent here
From Tube CAD:"It certainly looks unconventional, but is its operation as unconventional as its appearance? First, let's add some signal relationships throughout the circuit.
The triode receives the input signal at its grid. As the signal swings positively, the triode increases its current conduction and its plate voltage is pulled down, which then pulls down N-channel MOSFET Q2's source voltage, which in turn provokes a decrease in the voltage drop across its drain resistor, making P-channel MOSFET Q1 draw less current. When the input signal swings negatively, the opposite occurs; the triode draws less current and MOSFET Q1 draws more current, pulling the triode's plate voltage up. The capacitor coupled output transformer relays this amplified signal to the loudspeaker. In short, push-pull operation, not single-ended functioning, as MOSFET Q1 actively varies its current flow match the triode in anti-phase, just like every other push-pull output stage.
The patent claims that this a para-feed arrangement, but really is just a push-pull totem-pole arrangement of dissimilar output devices with a coupling capacitor attaching to the output transformer's primary, which allows us to use a non-air-gapped output transformer. In fact, we could just as easily use a bipolar power supply and DC coupled the output transformer primary at one end and ground the other end."
Do they understand what they are getting? Not a Single ended 300B triode, but a push-pull amplifier consisting of a Mosfet and 300B triode in combination..
Would they buy it then?
WE:
91 E — Western Electric - Maker of electron tubes and high fidelity
www.westernelectric.com
- The Western Electric Type 91E is a Class A, single-ended (SE), integrated amplifier for high-fidelity audio reproduction.
And the evaluation of the patented circuit here by TubeCad.
Patent here
US10256776B1 - Steered current source for single-ended class-A amplifier - Google Patents
A single-ended Class-A amplifier includes an amplification component (e.g., a vacuum tube) having at least an output terminal, a reference terminal and a control terminal. The control terminal receives a time-varying input signal. The amplification component responds to the time-varying input...
patents.google.com
From Tube CAD:"It certainly looks unconventional, but is its operation as unconventional as its appearance? First, let's add some signal relationships throughout the circuit.
The triode receives the input signal at its grid. As the signal swings positively, the triode increases its current conduction and its plate voltage is pulled down, which then pulls down N-channel MOSFET Q2's source voltage, which in turn provokes a decrease in the voltage drop across its drain resistor, making P-channel MOSFET Q1 draw less current. When the input signal swings negatively, the opposite occurs; the triode draws less current and MOSFET Q1 draws more current, pulling the triode's plate voltage up. The capacitor coupled output transformer relays this amplified signal to the loudspeaker. In short, push-pull operation, not single-ended functioning, as MOSFET Q1 actively varies its current flow match the triode in anti-phase, just like every other push-pull output stage.
The patent claims that this a para-feed arrangement, but really is just a push-pull totem-pole arrangement of dissimilar output devices with a coupling capacitor attaching to the output transformer's primary, which allows us to use a non-air-gapped output transformer. In fact, we could just as easily use a bipolar power supply and DC coupled the output transformer primary at one end and ground the other end."
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