Kicking off a series of reviews focused on British 12at7 tubes, we begin with the Mullard 12at7 featuring raised D-getters and solid plates. Manufactured at the iconic Blackburn factory in 1955, this represents one of the earliest production examples from Mullard that I have had the pleasure to experience. The sonic signature is characterized by a smooth and warm profile complemented by a notably sweet midrange, although the top end is slightly rolled off in this particular vintage.
Final Verdict: A classic, early-production tube prized for its warmth and liquid midrange.