? On using two taps on OT simulataneously

[booj]

Quote Originally Posted by Raiken
Q: Attempting to simultaneously operate a 4-ohm and a 8-ohm speaker from the 4-ohm and 8-ohm secondary taps of an output transformer...not a good idea---but, why?
A: If you run a 4 ohm speaker on the 4 ohm tap, it will reflect back, say, 8K to the primary. Now, if you also connect an 8 ohm speaker to the 8 ohm tap, it will also reflect back as 8K to the primary, so the tubes now are seeing a 4K load instead of the 8K they require. That's why it is a bad idea. Now, if you connected an 8 ohm speaker to the 4 ohm tap, and a 16 ohm speaker to the 8 ohm tap, the reflected impedance would be correct.

the only thing I see wrong with this is that if an 8 ohm load is connected to the 4 ohm tap it may change the reflected impednace to the primary by 2, but at that point, nothing is connected to the 8 ohm tap. Now you put a 16 ohm load on the 8 ohm tap. Doing that messes up the x 2 stuff you had going on before with the 4 ohm tap. Also having the 8 ohm load on the 4 ohm tap messes up the x 2 thing you are trying to get with the 16 ohm load on the 8 ohm tap. I don't think you'll get 50 watts anymore, but it does seem to be the best way to hook up the loads to the amp.