Audion Sterling EL34 Anniversary Integrated Stereo Amplifier (TAS 221)

Music Lovers’ Delight

History has been kind to Audion since Erik Andersson and David Chessel started the company in the late 1980s. It survived two decades in an age when the average lifetime of a startup high-end-audio company was less than five years. In 2000 Graeme Holland took Audion over from Chessel and moved operations to France’s Bordeaux region where he happens to live—in fact, to a large barn attached to the side of his house and converted into a custom-manufacturing facility. The transition was eased by “coercing” some of the Audion staff to move to France and continue working for the firm. That barn is now a working factory of 3100 square feet, of which 860 square feet are factory space and 430 square feet are devoted to transformer winding, baking, and testing.

Graeme tells me that since he took over Audion there have many improvements made to the product lineup based on market research, customer feedback, and dealer-led requirements. The $3499 Sterling EL34 Anniversary stereo amp is a sixth-generation product. Not only has the chassis been changed considerably from the early steel variety, but the circuit design has changed as well, as has the topology of the output transformer. Many of the internal components are now being made specifically for Audion, which manufactures all the output transformers in-house. Audion also prides itself on using components sourced from either Europe or the U.S. when possible, and is eager to maintain product quality and reliability. Where single points of failure have been found in the past, the circuits and/or parts have been over-engineered or over-specified to avoid such problems in the future. There are no production lines at Audion. One person builds an amp from start to finish, as experience has shown that such an approach engenders more pride and care during the assembly process.

Audion today continues to adhere to a basic philosophy of making affordable esoteric high-end equipment available to everyone and not a select few with deep pockets. Graeme says that he personally prefers “a system that is non-fatiguing and musical to an extremely analytical system where you crane your ears to listen to what they are saying in the background of Jazz at the Pawnshop for example [or] where a guy on a mixing desk didn’t properly change a level or a drummer dropped a stick. Our high-end products will retrieve this info and more, admittedly, but I maintain that a good amplifier is not only transparent but musical and engaging and a pleasure to listen to for a whole evening and more. I believe our amps are primarily musical.”

There are several versions of the Sterling EL34 Anniversary stereo amp. One uses a printed circuit board (PCB), another a hard-wired circuit. Another difference is packaging: One version is capable of switching up to five line-level inputs; another, more basic version has only a volume control. All versions are single-ended (SE) designs using a single EL34 per channel in pure Class A operation. However, the PCB version of the Sterling uses a Russian 6N1P dual triode as a voltage input/driver stage, while the hard-wired version uses the 6H23N, another fine Russian dual triode. The power supply is solid-state-rectified and uses a good quality CLC filter network. All filament supplies are AC.

The output stage is cathode biased for long-term stability. What is unusual though is the ultralinear (UL) connection, which is typically seen in a push-pull amp, but of course is also very much an option for single-ended pentode designs. The screen grid is connected to a tap on the output transformer so that AC screen current provides a form of power feedback to the output stage. The end result is an operating characteristic intermediate to that of triode and pentode, meaning that linearity is increased and distortion is reduced. There is also a bit of global feedback used for increasing the amp’s damping factor. Graeme tells me that the idea of single-ended UL dates back to Erik Andersson’s early days, in actual fact before Audion. Erik’s first design using this principle was apparently for Audio Innovations in the early 1980s. And the design was carried forward after Audion was formed. (I never understood the logic of trying to use a pentode or beam power tube without UL in a single-ended output stage. Yes, the payoff is increased power output relative to a triode, but tetrodes and pentodes are so inherently non-linear that they need help or else distortion products dominate the sound.) The Sterling EL34 Anniversary delivers 12 clean watts into an 8-ohm load. It is said to be suitable for use with loudspeakers of 89dB sensitivity or better. Note that only 8-ohm impedance taps were provided on the review sample; thus I would avoid using it with 4-ohm rated speakers, unless their sensitivity is well into the 90s. When ordering, however, you may specify 4 or 8 ohm transformer taps at no charge, or with selectable taps for a $70 up-charge.