>And if the power output was 20% higher than normal of the G2DAF design, that
>is a sign that the amplifier was overdriven.
With AB1, no grid current is permitted. With DAF grid current is
permitted. When positive grid voltage is permitted, peak anode currents
increase substantially.
>Since the plate efficiency is
>no different than the "standard" configuration, greater output indicates
>overdrive.
? Not by DAF rules. By AB1 rules, yes.
>Simply reducing the drive to get the same power input and output
>would have reduced the distortion.
>
>I can increase amplifier distortion on any amp that it at the normal limits
>by overdriving it. This is another way to assure failure.
>
>So, the amplifiers you listened to were being overdriven
? not according to DAF recommendations.
>and used tubes that
>you say were poor tubes to use in grounded cathode linear service. Good
>tests!
>
? The 4cx250Bs worked well with regulated screen supply and zero grid
current.
>Did they also use power supplies that sagged 50%?
>
? ______________________ .
- Rich..., 805.386.3734, www.vcnet.com/measures.
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