Driver Impedence and Interstage Questions

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I'm trying to understand the concept of driver impedence and how interstage transformers affect this parameter. For now, consider the working design to be single-ended, class-A. The output tube is an 845.
I understand that some output tubes (especially transmitting tubes) want a low impedence driver. This can be achieved by using a driver tube with a low plate resistance (6H30P, 6BX7, 300B etc.). Some designs use a kathode follower or a Mu-follower to get even lower drive impedence. (Someone please stop me if I'm getting anything wrong here).

So how does an interstage transformer affect the drive impedence seen by the output tube? Does the plate resistance of the driver tube get "reflected" through the transformer? Does the turns ratio affect this?
For example, would a driver tube plate resistance of say, 1200 ohms, be seen by the output tube as 2400 ohms if the transformer were wired for 1:2 step up? How about step-down? Would the 1200 ohm plate resistance be seen by the output tube as 600 ohms if the interstage were connected 2:1 step-down?
How would these connections affect the primary side of the interstage? In other words, would a 2:1 step-down connection change the plate load seen by the driver tube? Is there an impedence on the secondary side of the transformer that gets reflected through the interstage to affect the primary load on the driver tube--or is the driver's load established by the Henry's of the primary?
I'm guessing that with enough signal voltage to start with, a step-down transformer will allow me to get a low drive impedence without resorting to kathode followers. Obviously, a step-down interstage will throw away signal voltage so there must be enough to start with, (from preceding stages of gain).
Although perhaps an odd topology, connecting an interstage as Push-Pull to Single-Ended (and step-down 2:1) might produce enough voltage gain (from the push-pull pair) and still lower the drive impedence seen by the output tube-----or does a pair of push-pull tubes on the primary side result in "twice the effective plate resistance, compared to a single tube" and nullify the lower Z achieved by the 2:1 step-down connection?
Any help with these questions would be much appreciated.

Edits: 31/20/01

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Topic - Driver Impedence and Interstage Questions - Horn-a-copia 21:58:29 08/03/03 (3)

Re: Driver Impedence and Interstage Questions - KevinC 07:01:21 08/04/03 (2)

Re: Driver Impedence and Interstage Questions - Horn-a-copia 07:40:33 08/04/03 (1)

Re: Driver Impedence and Interstage Questions - KevinC 07:33:55 08/05/03 (0)

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