02-05-2017, 07:25 AM
Both valves are pin compatible but the 6V6 has a lower gm so if fitted alongside the EL33 there will be a mismatch increasing distortion. Most likely there has been no mods to do this as it fitting two different valves of different characteristics is not the correct way to do things. Two EL33's is the right way to go. These sets are excellent once restored.
