Aunt Corey's Homemade Buffered Passive Preamplifier

"An' then ya bring alla ground wahrs to uh, uh single po-wint..."

He looked just like I always pictured: jet-blueblack hair Royal Crown'd into that famous pompadour, the heavily lidded eyes, the .357 Magnum in case Robert Goulet appeared on any nearby TV screen...and the Weller temperature-controlled soldering iron.

"...Ah think ya need to bypass them big ol' electrolytics, too..."

I knew I was dreaming, but it didn't matter; I'd been wrestling with the problems of purely passive preamps for months, and was nowhere close to any real solutions. I'd built my own passive preamp after reading Ben Duncan's how-to article in Stereophile (footnote 1) but the initial astonishment at how much better it sounded than my preamp at the time gave way to complaints of restrained dynamics and the absolute need to use short/low capacitance cables on the preamp's output. I was convinced that a conventional line-stage was far inferior to the sonic purity of a high-quality volume pot, but the highish output impedance of my passive preamp caused problems with the lengths and types of interconnect I wanted to use. So when the King of Rock and Roll sauntered into my dream with a handful of parts and a roll of SN62 solder, I listened up.

"Gee, Elvis, where'd you learn all this stuff about audio design?"

"Hot damned TAMALE, son, Ah wuz a 'lectrician's apprentice 'fore I met Mr. Sam Phillips, y'know...an' truth be told, Ah taught David Hafler ever'thang the ol' boy knows. Ah remember the day Ah showed him how to wahr-up his output transformers; 'Man,' Ah said, 'tap that ol' primary out, hitch it 'tween yer plate an' yer center-tap, an' you'll have a whale of a tube amp!' But ya think Ah wanted people to know Ah knew all that stuff 'bout audio 'lectronics? Ya thank Ah could've had Ann-Margaret covered with nuthin' but peanut-butter an' 'nanner slices if she knew I could hear absolute polarity?!"

He wiped the Weller's hot, shiny tip on the wet sponge and ran a black unbreakable plastic comb through his hair.

"Man, the way Ah see it, ya got problems with a purely passive preamp (footnote 2) in that the impedance changes...hey...now, w-wait a minute! Ya got me describing this thang jus' like that ol' Ben Duncan cat used Alice In Wonderland to lay out his DIY project! No way, baby! Ah'm gonesville, man..."

He unplugged the Weller and wrapped the cord around the handle. I ran after him as he got back on his Harley and kicked the starter.

"But Elvis!" I cried, "What about my passive preamp?! What should I do?!"

He reached down to his jewel-encrusted belt-buckle and wrenched two silvery, spider-legged baubles from their fittings.

"Here, man!" he drawled, tossing them to me over the roar of the engine. "And remember; don't ever let nobody tell ya you ain't no good. Cuz as long as you believe in the power of The Sun Sessions, there'll be a place for you at the table of The King. An' uh, Jes' Say No, too..."

He gave his bike the gas and tore off into the blue night. And when I awoke the next morning to find a couple of metal-can buffers on my pillow, I knew why He had come. And now it's my job to tell you.



Footnote 1: Vol.11 No.2, pp.79-87.

Footnote 2: "An' be ready fer them angry-ass Manufacturer's Comments from The Mod Squad, First Sound, and EVS, too, but jes' tell 'em The King told ya it was alright, mama."

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