02-24-2013, 10:15 PM
Probably as AB pushpull (at least transistor ones are always AB). That means that mostly it is B (conducts for half-periode) but also conducts just a tad beyond that so both halves conduct at the same time when the tubes are almost open. That eliminates that infamous "step" that occurs when both halves do not conduct in B pushpull.
But say my 9-tube Zenith 9S262 has Class A Single-ended amp for the output.
Sounds good enough. The disadvantage of A vs AB is that one tube conducts all the time, hence lives shorter life. Also SE transformer is larger than Pushpull, due to the permanent magnetizing creating saturation, and so it is more expensive, often twice as.
But say my 9-tube Zenith 9S262 has Class A Single-ended amp for the output.
Sounds good enough. The disadvantage of A vs AB is that one tube conducts all the time, hence lives shorter life. Also SE transformer is larger than Pushpull, due to the permanent magnetizing creating saturation, and so it is more expensive, often twice as.
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