Originally Posted by

**Enzo** Lower resistance is good, but is not the main thing. The transformer still has to be a transformer. Your one turn to 50 turns would technically work. In fact on some TV sets, the heater winding for the picture tube is ONE turn of wire around the core of the flyback transformer. But the point of the transformer is to convey the power through the tubes to the speakers. There have to be enough turns on the core to drive flux through the laminations. You need to be able to generate a certain level of voltage across the speaker load AND at certain levels of current. Your one turn would not be able to induce that much current into the wire.

Your primary winding might be a 3000 ohm impedance and have a DC resistance of 30 ohms. If we had a perfect 3000 ohm impedance transformer, we could add a 30 ohm resistor in series with it on one end and have the same thing as my "real world" transformer. That 30 ohms is invisible to the tube. Now that imaginary 3000 ohms is only 3000 ohms IF the appropriate speaker load is present across the secondary. The transformer has no inherent impedance.

I have to say I am not sure what you are saying.

Why do replacement transformers list higher impedance? What impedance? If they give winding resistance, that is separate from impedance. If you actually mean impedance, well transformers are made to match certain tube impedances to certain speaker impedances. If we start with an 8 ohm speaker load, we then design a transformer with turns ratios that result in a reflected impadance of whatever tube you plan to use needs. EL34, 6L6, etc each expect a certain impedance for best operation, so a transformer is wound to match one tube to one speaker impedance. SO if the primary should be 3000 ohms for a certain tube, I would not expect them to make a 4000 ohm transformer for the application.

The transformer is an electrical equivalent to gears. gears can turn high speed low torque into low speed high torque. A gear has no inherent speed, the speed of one gear is proportional to the ratio of the size of it to another gear. By determining the speed of one gear, we can determione by ratios what the speed of the other gear will be. Likewise, if we know the input speed, and the desired output speed, we can calculate the ratio we need in gear size.

Impedance not mattering at all? I certainly am lost as to your point there, please restate it. If i have made confusing statements, please point them out so I might try to clarify. After power handling capability, impedance is the whole point of the transformer - it TRANSFORMS the impedance of the tubes into the impedance of the speaker.

You say you understand the resistance thing, but when you say something like this it leads me to think you really don't have it yet. The resistance - not impedance - of the speaker and the transformer windings have nothing to do with each other. it is the impedances that need to match, not the resistances.

## Bookmarks