[1000mp] Re: Quadra Warranty

[Billy Cox]

>Sorry...you are right. I got my wires (grids) crossed, thinking that the
>3CX1200A7 had a 4W grid-dissipation rating. I stand corrected.

Hi Adam ... not a problem, and I learn much from your posts on here! TU ...

>Here are the grid dissipation ratings for some representative Eimac 
>and Svetlana tube types, from the data sheets:
> 
> Eimac: 3CX1200A7: 50W
> 3CX800A7: 4W
> 3CX400A7/8874: 5W
> 3CX1500A7/8877: 25W
> 
> Svetlana 4CX1600B: 2W (ouch!)
> 
>One can work around the problem of grid damage in a tube amplifier 
>by using a tough tube such as the 3CX1200A7or 8877 (25W is not bad).

Very true, the 8877 (and many of the others in the above list) also require
a 2 - 3 minute "warm up" time. That may seem like eternity for some ...

>In a solid-state amplifier, protection is not an option. 
>Neither is ALC - it is the amplifier's first, or only, line of defense.

Adam, I know you have measured the output verses drive on the
Quadra there ... Have you also made any measurements as to
the differences as to with and without the ALC as to the quality
of the signal?

Seems like we have gotten away from using ALC with many
of the solid state to tube PA setups <as compared to years
ago, when we always seem to use ALC with tube exciter
to tube PA setups.> 

Just wondering what happens (outside of losing some much
needed protection or insurance against PA damage) when
the solid state exciter does NOT use ALC with a solid state PA?

73 Billy AA4NU