For Push and Pull application,
I got great results replacing KT66s with NOS 7027A for my application.
The 6L6GCs lacks control in lower frequency when compared to 7027A. Some might like the rounder and fuzzier sound of the famous black plate 6L6GCs.
The Russian and Chinese KT66s sounded even worst than the NOS 6L6GCs. A bit harsh which cause long term listening fatigue.
I don't really hear much difference between the RCA/GE/Sylvania tall/short bottle 7027As. Some of my buddies thought the RCA/GE sounded slightly warmer then Sylvania but we can't tell the difference during blind test.
I got great results replacing KT66s with NOS 7027A for my application.
The 6L6GCs lacks control in lower frequency when compared to 7027A. Some might like the rounder and fuzzier sound of the famous black plate 6L6GCs.
The Russian and Chinese KT66s sounded even worst than the NOS 6L6GCs. A bit harsh which cause long term listening fatigue.
I don't really hear much difference between the RCA/GE/Sylvania tall/short bottle 7027As. Some of my buddies thought the RCA/GE sounded slightly warmer then Sylvania but we can't tell the difference during blind test.