M & O

Marconi - Osram later known as M&O Valve was founded in 1919 by the joining of the Marconi Wireless Telegraph Co., and The Edison General Electric Co. (Osram). This formed, what was at the time one of the largest pools of electron tube making experience in Great Britain.  They continued making fine radio tubes, mostly for use in Europe until the Post WW-2  Hi-Fi boom hit in the 1950s and audio began to be big business. Big beam-power & pentode business like the 6L6 by R.C.A.  and Tung-Sol's 6550 in the U.S. and the EL-34 in Europe. Well M&O was not one to be left behind, so they sat down and carefully designed three, direct drop-in competitors for all three of the new high-power audio outputs. These were of course the KT-66 for the R.C.A. 6L6, the KT-77 for the EL-34, and the KT-88 to compete with Tung-Sols 6550.  These tubes are some of the most suave, rich, classy pentodes ever made period. They have the real-thing greatness that is so rare these days. It has offended me for 14 years that the Chinese, Russians and their American distributors have had the audacity to put the designation KT-66, 77, & 88 on any and all of the JUNK that came down the pike! And, by how many members of the U.S. audiophile press were and still are to this day, standing in line to glorify the emperor's new clothes. For the entire first half of this century, the very finest minds in the world were applied to making these tubes, starting with Thomas Edison. To give you an example of what goes onto the making of these tubes let me relate an event that happened a couple of years ago. I had a visitor from Germany who is a super sharp chemist and hangs out with the aristocrat types in Europe. He is a member of the Royal Academy of Science but doesn't know, or care much, about tubes or audio. So, he is sitting in my living room having coffee and he looks down at some tubes lying around and launches off about how one of his elderly friends at the Royal Academy used to be one of the chief chemists at M & O.  They used to talk about corporate culture, trade secrets and how closely guarded many of the chemical & metallurgical processes were, as they had been worked out over the proceeding half-century. He mentioned that the old guard, Edison & Marconi,  (and the next generation after) set the example of guarding important formulas & processes because of the patent wars they had fought all their lives. Even at that, he said with all of the equipment in front of you and everything running well, that the ticklish nature of making the finest tubes (inconsistencies in raw materials etc.) is more like cooking than anything else and they knew that someone without their experience could never make tubes quite the same. Well all I can say is that these guys had it because it is now 1999 and damn near of all of the hundreds of real KT-88s, 77s & 66s I have distributed over the last 6 years are still making sweet music for their purchasers! This includes 20 KT-88s that run in a pair of Jadis JA-200s that were tubed up in 1995. Not only have they not missed a single beat but they still all measure and look almost NEW! I have had my own personal set of 4 for 16 years and they are still perfect. M & O made these tubes from 1957 until 1976 or so and then re-introduced them in 1982. Unfortunately these later ones were, of course,  not up to the previous production quality, and it was all over for good in 1988.   

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