The TELEFUNKEN EL34-TK has been designed to handle a slightly higher grid voltage than the traditional EL34. Offering a tight low end and smooth mids, it will bring new life to guitar and hi-fi amplifiers while retaining the historic tone TELEFUNKEN tubes have always been know for.The EL34 is smaller in diameter and taller than the 6L6 and is capable of a higher plate voltage; factors that help give the EL34 its unique output stage properties. The EL34 is a high output pentode tube as opposed to other output tubes like the 6L6 and the 6550, which are beam tetrode tubes.
Mullard, which was a subsidiary of Phillips, originally released the EL34 in 1953. EL34's are most commonly used in pairs in a Class AB1 push-pull configuration. This EL34 is found in many amplifiers that offer the "British tone", like Marshall and Hi-Watt, where the 6L6 is more commonly found in American made amps like those from Fender and Mesa Boogie.