It seems that the OT used for Rockets, Express and Liverpool are mostly the Toneslut 6.6k/5.5k version.....
OTOH - 4xEL84 usually uses around 4k, which also  goes for 2xEL34.....
Nothing wrong as such with the higher impedance, but how much does this influence the output power, - and BTW-  have any of you measured output power from these amps with 6.6 k? ??
			
			
									
									
						OT Transformer confusion
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