Vintage 1970 Dynaco Dynakit Mark III Monoblock Tube Amplifier Serial Number 3111826 with Spare Set of NOS Tubes. IT WORKS!!!  The identification stamp (1377040) on the bias adjustment indicates that the potentiometer, part number 137 was manufactured on Monday, February 9th, 1970 (the 40th day of 1970). Since, Dynaco went through parts regularly, it is fairly safe to assume that this unit was manufactured early to mid 1970. This amp was last used in the early to mid 1980's and has been in storage ever since. I believe it is all original, except for the RCA input, which has been replaced with a 1/4" type jack. I also noticed that the strain relief on the power cord is not present. I am not sure why, but the power cord should probably be replaced, anyway. It is still in good condition with no nicks or cracks, but it does feel a little stiff. This unit was predominately used to drive the tweeter horn section of a large 3-way PA system for most of it's life, only producing frequencies above 2500Hz. I was pleasantly surprised to see that it started right back up where it left off almost 40 years later. I tested it with a single 4ohm Tannoy Reveal speaker, connected to the 4ohm tap. THE TANNOY REVEAL IS NOT INCLUDED IN THIS LISTING AND NO FURTHER TESTING WAS DONE. I posted a video of this test in the picture section. There is a spare set of (2) 6550A's (1) 5AR4/GZ34 and (1) 6AN8A new old stock, never used, Made in U.S.A. General Electric Tubes that have been stored in the same zip lock bag since day one (1970). There are normal scratches, blemishes and cosmetic wear from use, along with some rust from age. All of my listings are sold AS-IS, so please inspect all of the pictures carefully to determine the item condition for yourself. Remember it is 53 years old and like all old electronics, it may behave unexpectedly. It will be over-packed with plenty of bubble wrap and shipped with insurance via U.P.S. unless you prefer a different method. Thanks for looking!!

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