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PP to SE Idea

9/2/1999 5:53 AM
John Kos
PP to SE Idea
If the reason for not being able to use a PP OT as an SE OT is a DC bias current imbalance and thus possible core saturation as stated in the wonderful Tube Amp FAQ, then why not allow the "other" bias current to remain as it would normally be for a PP situation? Assuming a true class A amp, this would be as simple as removing the drive from one of the output tubes. Right?  
Obviously this isn't an efficient (in several ways... wasted energy, perhaps uneven tube wear, inefficient power transfer in SE mode, etc.) means of obtaining SE operation; but, it does seem to be an easy means to have switchable PP/SE (as well as full power/reduced power) operation.  
Does anyone know why I shouldn't try this idea out?  
John Kos

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