Just sold the 10th pair. Last 7 pairs sold for $660 or more per pair. Excellent feedback both here and on our other site!! This is the 11th EXCELLENT NOS PAIR of 6900 Gold Pin made in USA by Tung Sol and retested, rebranded by MU . Bendix also purchased the vast majority of its 2nd generation 6900 stock from Tung Sol. These are NOT MU manufactured and in fact I've never seen a true MU manufactured 6900. They bought all the surplus stock of 6900's and tooling to make them from Tung Sol and have never produced any themselves. Each tube was retested by MU and then labeled MU and sold to the military.
Extremely rare and the best you will ever own. These are conservatively rated at 10,000hours in a pulse application. Audio circuits will see longer life.This is an excellent testing matched pair. Current matched internally and externally as well, for excellent push pull circuits such as drivers or as stereo triodes. This means BETTER sound than a standard unmatched pair or a pair matched only for transconductance.
Truly the very best sounding all all the twin triodes we've ever auditioned. They best the ECC32,34, all the 5687 and 7119 (7044) types, as well as any 6SN7 we've heard, 437A's etc. Ceramic insulators, heavy Nomex glass, gold grid wire, tungsten pins with gold plating, microphonic reducing springs, etc. These are tested at 500G's and rated at 300G's /... read more