AUDIO VALVES: EL37 CV586 CV1947 PP60 6L6G 5881 OUTPUT PENTODE

The EL37 audio output valve is of pentode configuration and is Mullard’s answer to the mighty KT66 beam tetrode. These meaty beasts could deliver up to 70 Watts at 2.5% distortion when used in push-pull.

 Developed from the earlier EL31 and rerated to have higher anode dissipation, the EL37 in characterised by having a massive mutual conductance when compared against it’s contemporaries. Indeed, 11.0 mA/V is almost twice the value of that shown by the KT66 or the 6L6.

 Introduced in 1946, the EL37 was superseded by the introduction of the EL34 some 8 years later, praised for their scarcity, their exceptional sound and ease of driving they are keenly sought for audio amplifier and guitar amplifier applications today, key examples of which include: -

 Dr. Z Route 66

 Marshall Bluesbreaker JTM45 MKIV 1966

 Marshall Bluesbreaker reissue 1964

 Marshall JTM45

 Metro Amp (George Metropoulos)

 Metropolis JTM-45 2009

 Pure Sixty-Four The "64" Head

 QUAD II

 Soultone 1986ps

 THD Bivalve

 Victoria Regal 2