AG6K:
> With AB1, no grid current is permitted. With DAF grid current is
> permitted. When positive grid voltage is permitted, peak anode currents
> increase substantially.
SM3BDZ:
Its quite true that the DAF design permitts grid current. Thats why you should
compare the design
rather to GG than AB1. When a GG amp, or a AB1 amp, is driven to excessive grid
current,
saturation and flat topping occurs.
My assumption is that here we have a substantial different compared to the DAF
design.
When grid current increase due to high drive in a DAF amp, the screen voltage
also increases
and thus sets the roof higher.... That should improve distortion
characteristics, and make the flat topping "softer" !?
This is only a theory, but to me it makes sense. Please tell me if I´m wrong!
K7FM:
> >Since the plate efficiency is
> >no different than the "standard" configuration, greater output indicates
> >overdrive.
>
> ? Not by DAF rules. By AB1 rules, yes.
SM3BDZ:
???
K7FM:
> >So, the amplifiers you listened to were being overdriven
AG6K:
> ? not according to DAF recommendations.
SM3BDZ:
And exactly WHAT is the DAF recommendations??
73 de Lars/SM3BDZ (working on my DAF website...;-)
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