[Amps] SB220 mystique

[John Lyles]

I've always considered the 220 as sort of a Dynaco project. David Hafler created the Dynakits and brought high quality but reasonably priced 'component' audio gear to thousands of stereophiles. Eventually, there was a following of modifiers that POOGed the Dynas, the PAS, the SC70, the Mk iiis, etc. Many mod articles were found in the 1980s in Audio Amateur, Glass Audio and other magazines. Everyone had their favorite hack, as the Dynas were easy to cut into, to add circuitry, to make tweaks and 'improve' the sound. I got Haflers amlifiers and preamps, and they all were modified and 'improved'. I still have three of the amplifiers around, 20+ years later. Just like the 220. The SB220 is a similar box, in that there are lots of mods out there, some good and some not so, but despite that, hams love to mess with it and add the features that it missed. Others are just content with a working amplifier, no frills, no microprocessor. 
I lucked into a 220 in 1992, late in the game, at a local hamfest for $250 or so. I made plenty of changes to mine, it is now customized to my liking, and I'll keep using it. Simple yet powerful with a pair of 500Z.  

73
John
K5PRO