I read that a MOSFET can simulate a Triode to produce even harmonics, said to give a more pleasing listening experience. As a Source Follower a massive 3rd harmonic is produced, but as a Grounded Source the harmonic is the 2nd. Your comments, please.
https://www.vishay.com/docs/91202/irfp140.pdf
The idea is to force the mosfet working in non linear region highlighted below.
The idea is to force the mosfet working in non linear region highlighted below.
Notice the output swing (volts) - a 'semi-triode' would do 1/10 of the tube range and be very happy.
A triode has concave curves, whereas without adjustment gear, semi's have convex curves.
Also, the triode (or a 'triodized' semi) has a 'moving' transfer characteristic, due to the anode (drain/collector) voltage.
Without the exception of V-fets (and comparable devices), no other semi's exhibit this behaviour.
A triode has concave curves, whereas without adjustment gear, semi's have convex curves.
Also, the triode (or a 'triodized' semi) has a 'moving' transfer characteristic, due to the anode (drain/collector) voltage.
Without the exception of V-fets (and comparable devices), no other semi's exhibit this behaviour.
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Common source has more distortion. If you are after distortion, use circuits that have common source.
I have a class AB design with JLH style mosfet output. To create more distortion, you could replace the current mirror in LTP with a resistor to lower the open loop gain.
Here is a very simple MOSFET amplifier. I don't have the name for it. The output is similar to JLH output stage, but it can actually work in class B with MOSFET. Achieve good performance with relatively small number of parts. It also has the capability of almost rail to rail voltage swing, which is the weak point of most other MOSFET designs.
[EDIT] Added constant current source for the bias. Thus, the power rail fluctuation will not affect the bias.
[EDIT] Added constant current source for the bias. Thus, the power rail fluctuation will not affect the bias.
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Do you think mosfet arranged in bastode connection's loadline "triode" enough?
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nice, I came to comment on the user 'sulcorebutia' I used to have those but not anymore, I sold them when I moved places. I thought you are from Bolivia but then I see the flag beside the name. 🙂
I gave up on this plan and just use a 6922 dual triode. Cheaper and no problems yet.
12ax7 also works well and can be had for $ 15.
12ax7 also works well and can be had for $ 15.