saying the tweeters in 2AX and 3a's were actually same - no difference in 4 ohm vs 8 ohm as previously thought. Jim: That thread as noted, was about the 1-3/8-in.-diam. phenolic-dome tweeter (dc resistance nominally 2 ohms) designed for the AR-3 and later used in the old 2ax (sn <125,000). It was not used in the -3a! Sorry if that wasn't clear. That was one of the only cases anyone has seen where AR used the same driver in both an 8- and 4-ohm speaker. Cheers,