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Overdrive?

If you're running, say, 2 2879 transistors good for about 100w pep each, or 200w pep/pair @ 12vdc that would provide 50w carrier and 200w pep AM without ever over driving, however it would be about 55% efficient class AB, 75% class C which runs cooler and requires less current for the same output.

The reason for the class C distortion is the fact the transistors switch off until a small percentage of their power is demanded so they lose that small percentage across the notch between the positive and negative half of the sine wave, causing a gritty sound like the edge of a piece of cardboard dragged across 40 grit sandpaper.
Over driving them only adds to the nasty edgy class C sound on AM if too much carrier is demanded because the transistors are saturating.
The carrier on AM keeps class C sounding clean on AM because it keeps the transistors on so the audio has a clear path to flow instead of like SSB where there is no carrier and the audio does the work of turning on and keeping on the class C transistors, losing some of the clarity across that notch.

<blockquote data-quote="Needle Bender" data-source="post: 353309" data-attributes="member: 13339">Overdrive?If you&#039;re running, say, 2 2879 transistors good for about 100w pep each, or 200w pep/pair @ 12vdc that would provide 50w carrier and 200w pep AM without ever over driving, however it would be about 55% efficient class AB, 75% class C which runs cooler and requires less current for the same output.&nbsp;The reason for the class C distortion is the fact the transistors switch off until a small percentage of their power is demanded so they lose that small percentage across the notch between the positive and negative half of the sine wave, causing a gritty sound like the edge of a piece of cardboard dragged across 40 grit sandpaper. Over driving them only adds to the nasty edgy class C sound on AM if too much carrier is demanded because the transistors are saturating.&nbsp;The carrier on AM keeps class C sounding clean on AM because it keeps the transistors on so the audio has a clear path to flow instead of like SSB where there is no carrier and the audio does the work of turning on and keeping on the class C transistors, losing some of the clarity across that notch.<img src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f642.png" class="smilie smilie--emoji" loading="lazy" width="64" height="64" alt=":)" title="Smile&nbsp; &nbsp; :)"&nbsp; data-smilie="1"data-shortname=":)" /></blockquote>

[QUOTE="Needle Bender, post: 353309, member: 13339"] Overdrive? If you're running, say, 2 2879 transistors good for about 100w pep each, or 200w pep/pair @ 12vdc that would provide 50w carrier and 200w pep [B]AM[/B] without ever over driving, however it would be about 55% efficient class AB, 75% class C which runs cooler and requires less current for the same output. The reason for the class C distortion is the fact the transistors switch off until a small percentage of their power is demanded so they lose that small percentage across the notch between the positive and negative half of the sine wave, causing a gritty sound like the edge of a piece of cardboard dragged across 40 grit sandpaper. Over driving them only adds to the nasty edgy class C sound on AM if too much carrier is demanded because the transistors are saturating. The carrier on AM keeps class C sounding clean on AM because it keeps the transistors on so the audio has a clear path to flow instead of like SSB where there is no carrier and the audio does the work of turning on and keeping on the class C transistors, losing some of the clarity across that notch. :) [/QUOTE]

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