My first Tube Amplifier

dynaco stereo 70.
I was scrapping large high voltage lab power supplies at the time, I was getting them for free, as scrap, from the local university. I decided to modify the dynaco power supply.
I had the b+ rail up to ~10,000uf of storage.

My first tube amp was an early McIntosh.  When I had children I had to put it away because they would play with the tubes.  Later sold it, regretted this.  I’m now 66, retired.  When I was 35 and my children were older, I purchase a used Harman Kardon Citation II and had it rebuilt by the Master Jim McShane.  10 years later I purchased a second identical unit which has also been completely rebuilt with the best Mundorf Supreme SGO capacitors throughout.  I use them to bi-amp a pair of Meadowlark speakers which are phase and time coherent.  The Meadowlarks love those tube amps.  The amps are nearly as old as I am, vintage 1960, but to my ears present a wide an accurate soundstage, causing the speakers to disappear.  I’ve tried SS several times, but like an acquired taste prefer the tubes.   The preamp is also tube, a Dynaco PAS-4 (1995 Panor version not the original Dynaco’s).  Also fully rebuilt.  I’ve spent years finding the right tubes for this unit and determined it best likes the frame grid Tesla’s (E83cc and E88cc), which are replicas of the famous Telefunken 803S.  Telefunken and Tesla are the only two companies that were able to make these tubes, the technology which has since been unreplicated.   The frame grid wire is so thin it is nearly impossible to see with the human eye, which is why others have been unable to make this type of tube.   It contributes to a so called holographic signature with lots of detail.  

A Mullard 10/10, which actually puts out 12 watts. Built in 1966 but never used and bought by me around 2000, still with the original Mullard valves. It has been recapped and the volume pot replaced and is still in occasional use. Looks like hell and sounds like heaven.

@jond

Stock 6550 tend to be bright but if you get Nos tube it sounds much better.

September 1981: Bought a rare single-chassis dual-mono Futterman H3aa (#111AB) OTL amp from Bob Heenan at Q Audio, Cambridge MA. $750. Used it with a pair of Quad 57's (22585, 25391). Sold it July 1991 for $600. It needed new tubes and servicing. Should have kept it! Anybody out there know what happened to it?