You are served. In the movies, that's the inconvenient gotcha moments when the court summons or subpoenas are delivered. Here it'd be a man in brown, with a box at the bottom of the stairs. But even before he showed up, I'd been reminded of the long since discontinued $2'495 Mesa Engineering Tigris. In his 1999 Stereophile review, Chip Stern described it thus: "The Tigris is built as a dual monoblock, with its active line stage employing a pair of 12AX7 tubes per channel. As for its power section, the Tigris is the only audiophile amp I know of that uses two different types of output tubes—four EL84s and two 6V6s per channel—operating in two different classes of power through a common transformer. The EL84 tends to be fast and musical, with a sparkling high end and a sweet, airy midrange. However, it's somewhat lacking in low-end heft and when pushed too hard, evinces a harsh edge. On the other hand, the 6V6 has a big round warm low end with a lush quality in the presence region of the midrange, but tends to get tubby and indistinct when pushed to its limit. (In guitar amps, when pushed into clipping, the EL84 tends to snarl whereas the 6V6 growls.)"

If you fail to spot the connection, it's the 6V6. Whilst quite popular in guitar amps, one rarely sees it in hifi machines which do embrace the EL84 and EL34. The 6V6 goes back to RCA, Kenrad and 1936. Later Fender amps like the Champ, Princeton and Deluxe made it popular. Mesa Boogie's Mark I, Mark IV and Lone Star can run it. Current production glass remains available from China, Russia and Slovakia. Branded ElectroHarmonix, JJ, Ruby, Shuguang, TAD, Tung-Sol et al, it sells for ~$25/ea. European and US new-old stock could be labeled Amperex/Philips, Brimar, GE, Mazda, Mullard, Raytheon, RCA, Sylvania or Westinghouse. Due to relative similarity, adapters allow an amplifier with 6V6 octal sockets to take the mini noval-pinned EL84/6BQ5 though reverse adaptors don't exist. The beam-power 6V6 tetrode is a scaled-down 6L6 and its application notes list about 5Wrms for a single-ended tube and 14Wrms for a push/pull pair. Some guitar amps may put from 400-490V on their plates to harness from 20-30Wrms, albeit at high >5% THD and with much reduced life expectancy. Against these numbers, we appreciate how Alexey runs his at about 50% capacity for low distortion and long life; and how his settings ought to hold back some headroom.


The 12AY7/6072 belongs into the 12AX7 family but has lower gain and draws more current. Current production comes from ElectroHarmonix, JJ and TAD. It and the 6V6 were popular in so-called Fender tweed guitar amplifiers from 1948-1960. Their generic name derived from their varnished cotton twill covers which suggested tweed on feel and look. Read up on these two tube types in musical instrument catalogues and you'll see them referred to as Blues bottles for their warm tone and sweet top end.



Ever wondered what customs might make of various hifi appliances during this age of heightened airport security, especially valve gear and NOS tubes imprinted with 50-year old Cyrillic script of possibly Russian military origin? How to discern whether it's really an explosive device or illegal transshipment of classified parts? The decisive response is called the warehouse scan. Of course one must still recognize what one looks at, here a black box with knobs and 'valve integrated amplifier' declaration. Whilst Alexey's parcel was originally scheduled for 2-day delivery like the last one, the first customs inspector declared the accompanying contents declaration insufficient. He demanded more. When Alexey complied, alarms went off. The package was now opened for inspection. This created more confusion. Customs emailed him the below photo as proof why they needed further explanations. What in unholy hell was this degenerate capitalist contraption? As Syomin put it, he now was obliged to fill out another 50 pages of obscure bureaucratese documents. He was concerned over how Moscow's border personnel had treated and reboxed the contents. But things were entirely out of his hands now. Fingers crossed. A prayer to the tube deities.


Delivery was on a gloomily overcast rather rainy day. The mood was sombre. As it turned out, the only thing customs really managed to break were the four screws which had held down the wooden crate's cover. Instead of replacing them—how does one shear off every single screw?—they'd stuck to thick UPS tape instead. This thankfully did the trick as the UPS man heaved the crate sideways up the stairs without spilling my beans.


Once landed in the living room, Blondie the cat found this crate of exceptional interest. She clearly viewed it as the feline edition of the Moscow Times. She duly began to read it in the nosiest of details. With my far lesser olfactory gifts, I detected no hidden messages and proceeded instead to pop the bent-metal hood. What greets the prying eyes are a 3:1 longitudinal division demarcated by a metal divider to which mounts the power supply board with the toroidal line transformer. The majority of the space is occupied by two green tube boards with fat traces that end in proper screw terminals on either end and two output transformers adjacent to the power toroid. Seven chunky blue box capacitors and a few resistors make up the remainder of each tube board. The construction is very tidy and impressively 'mature' for a machine that was deliberately positioned and priced as a rececession buster special.