Yes, Ghostrider, the output impedance of course is a current limiting factor as more and more of the output voltage is dropped across the output section as opposed to the load as the load impedance is reduced.
However in the case of the ARC this is not a serious issue with a 6 ohm load. So the issues of a 'high current' amplifier are rendered moot, for the most part.
Were it a 3 ohm load, I think a different solution (amplifier) might be advised. There is also a guy on the ASOG (otlamp.com) named Paul Speltz who makes a torroidal autoformer (a variation of one we used to make) for this sort of application. It has taps for 4,3,2 and 1 ohm loads and sets the amplifier load at 16 ohms. Works quite nicely on those otherwise hard to drive loads that tubes don't normally like.
Allows one to use tubes with, say, Appogee Scintillas, if you could find a set these days. For the most part though 3-4 ohms seems to be the most challenging most speaker manufacturers are doing these days.
However in the case of the ARC this is not a serious issue with a 6 ohm load. So the issues of a 'high current' amplifier are rendered moot, for the most part.
Were it a 3 ohm load, I think a different solution (amplifier) might be advised. There is also a guy on the ASOG (otlamp.com) named Paul Speltz who makes a torroidal autoformer (a variation of one we used to make) for this sort of application. It has taps for 4,3,2 and 1 ohm loads and sets the amplifier load at 16 ohms. Works quite nicely on those otherwise hard to drive loads that tubes don't normally like.
Allows one to use tubes with, say, Appogee Scintillas, if you could find a set these days. For the most part though 3-4 ohms seems to be the most challenging most speaker manufacturers are doing these days.