Tung-Sol, 6550, old vs new
I'm could not find a thread with a " A-B comparison, so I of these two 6550's so did it myself. I have come to the conclusion that advice is good but, advice is sometimes biased towars that person liking. ( mine will be as well ) I have read many times the original Tung-Sol 6550 is the best 6550 - bar none - So I finally went out on a limb and purchased some original Tung-Sol, and also some current issue Tung-Sol. I don't have an expensive tube tester so I cannot test for plate voltage, but I can test for emissions, leaks, and shorts. My original issue Tung-Sol passed all 3 tests so I took a chance and popped them in! And my response was.....
Wow! Very open sounding, a lot of air without being bright. Excellent imaging, and very holographic, with excellent bass. I have listened to the following 6550's: SED winged C, Penta Lab's 6550, GE 6550A, and Tung-Sol reissue 6550. So I have not yet heard all there is to offer so my opinion is biased. Of course if there is anyone out there that would like me to try out their favorite 6550 in my comparisons, feel free to send me a quad :) For what it's worth I have also listened to some of the KT88 family: Sovtek, Telsa, and SED Winged C.
Back to the AB comparison. The Old Tung-Sol beat the reissue in every category except perhaps in sweetness ( IMHO ) the reissue had a sweeter midrange. Actually I found the reissue to be warmer overall. I once thought the SED Winged C was the best current 6550. However after listening to the Tung-Sol reissue I have changed my tune. The reissue is not as good as the old Tung-Sol, no way! But it is quite good for a current issues tube!
But that original Tung-Sol 6550? Best I have ever heard!