Western Electric Type No.91E integrated amplifier

During my 30-odd years inhabiting New York City’s Greenwich Village, I’ve seen many things come and go. Today’s Village buzzes, blasts, and bellows in every direction, change itself the only constant.

Once the province of printers, factories, piers, and the maritime trade, the Far West Village, from Varick to Greenwich, plays host to a looming Disney megaplex. Concrete office blocks, empty in the 1990s, are choked with condos offering wraparound frontage, their storefronts touting Botox (“Wrinkle Prevention Studio”), cosmetic dentistry (“secretly straighten your teeth”), and bootcamp gyms (“smash your fitness goals”). At Barrow Street stands the old film-noirish Keller Hotel, its Hopperesque HOTEL sign weathered by time and grime. Farther uptown, former slaughterhouse buildings host Apple and Google offices. The nearby Ear Inn, a classic watering hole and neighborhood haunt, stands strong.

At 463 West Street, facing the Hudson, a massive, Neoclassical, 12-story building dominates its block. More than a century old, its copper-clad roof has turned a jaundiced shade of green. Proud and mysterious, its colossal Gothic gates are chained. Traffic rushes by, unaware of its historical significance.

In the 1990s, drummer Ken Micallef rented a subterranean rehearsal space in the building. (Then, as now, it is home to Westbeth Artists’ Housing.) Ken—I—was unaware then that the quiet man who took my cash was Paul Bley, the jazz pianist who influenced Bill Evans, Keith Jarrett, and drummer Paul Motian. (Motian eventually left Evans to work with Bley.) The building was designated a National Historic Landmark in 2011, but I’ve never found a plaque there; unlike many large European cities, New York City is distinctly sparing of plaques. It’s as if the city is worried they would hamper development.

463 West Street is a national monument not because jazz musicians worked there—and not because Ken Micallef rented rehearsal space there—but because between 1897 and 1966 it was home to Western Electric, the applied-research division of AT&T, parent company of Bell Laboratories. AT&T/Bell Labs was the source of many hi-fi–related inventions including the vacuum-tube amplifier, the transistor, negative feedback, the world’s first wedge-based anechoic chamber, and digital audio. (Harry Nyquist and Claude Shannon, who were involved in the development of the eponymous fundamental sampling theorem, did their work at Bell Labs.) Indeed, the first low-distortion, wide-bandwidth recording apparatus—hence, hi-fi recording—was developed at Bell Labs in 1925 (footnote 1).

The Western Electric division’s own creations include the Orthophonic phonograph, the Westrex cutting-lathe system, the 300B vacuum tube, considered by many the greatest triode power tube ever made, and the 1936 WE 91A single-ended triode (SET) integrated amplifier, which powered cinema systems across the country.

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Reincarnation
Following the 1974 antitrust suit against AT&T and the consequent 1982 dissolution of the Bell telecommunication system, Western Electric spun down. In 1995, the company’s tooling, schematics, intellectual property, and name rights were sold to entrepreneur Charles G. Whitener. In 1997, Whitener’s Western Electric resumed manufacture of the Western Electric 300B vacuum tube, first at Western Electric’s Kansas City works, then in Huntsville, Alabama, and finally to a new factory in Rossville, Georgia, equipped with hi-tech hydrogen-reduction ovens, automatic cathode-cleaning lines, flashy laser-welding systems, a modern water-deionization system, and an updated testing system. Earlier this year, he announced that his company would start producing several other vacuum tubes: 12AX7s, 12AT7s, 12AU7s, 6550s, and 6L6s (footnote 2). If, as seems true, Whitener is determined to elevate his Western Electric to the glory of the original brand, he’s off to a hell of a start.

Whitener’s 15-strong engineering team works in a state-of-the-art facility where, in addition to 300B vacuum tubes, they manufacture the 91E integrated amplifier ($14,999), modeled after the company’s early WE 91A amplifier.

“The goal, from the beginning, was to break through with a SET amp that allowed the 300B to perform at a never-before [heard] level,” Whitener wrote in an email. “There are new 300B amps every year from other manufacturers. Our contribution needed to be something significant, something powerful that only Western Electric could pull off.”

Design considerations
Whitener claims that the 91E, which was developed by a team of engineers over a period of 10 years, retains what’s best about the early WE 91A—its delicacy, bloom, openness, and tonal magic—and adds modern improvements. “You’ll find a solid low end and extended highs. We hoped to retain the clarity of the original 91A’s midrange as a SET 300B amp. The 91E has zero negative feedback, both local and global. The design of a SET amp without negative feedback is a difficult challenge and requires selection of only the finest components in the audio chain. These factors account for the incredible soundstage performance of the 91E. THD and damping factor may measure better in push-pull configurations but not without compromising musicality and soundstage. The 91E has proprietary topology that all but eliminates audible noise.” It also has remote control and Bluetooth, which Western Electric founder Elisha Gray could hardly have imagined.

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“The 91E uses Western Electric’s patented Steered Current Source (SCS) technology,” says a description on the company website. “The unique parallel feed topology contributes half of the AC current to the plate (anode) of the 300B by modulating quiescent current. As a result, half of the power dissipation occurs in the tube, allowing for greater power output.” (The 91E is rated at 20Wpc into 8 ohm with 10% THD.)

“Part of [the reason for] the increase in power is [that] we’re running the 300B in Class A2, grid drive positive,” Whitener explained. “The SCS circuit always keeps the power dissipation of the tube within the safe operating area (SOA), which of course extends the life of the tubes.”

The 91E uses a “stepped logarithmic attenuator,” the product’s webpage explains, “to mimic the response of human hearing. The attenuator consists of discrete resistors in a ladder configuration that are switched in and out of circuit to produce a logarithmic attenuation of the output signal.”

“It’s similar to an audio taper in potentiometers,” Whitener added. “Stepped attenuators have less noise and superior channel-to-channel tracking ability compared to motorized potentiometers. In essence, this microprocessor-controlled stepped attenuator uses relays to engage each discrete resistor in circuit and is accomplished with software that emulates a DAC. It complements human hearing with an algorithm for audio taper.”

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When the 91E is powered, a gray image of Western Electric’s winged Golden Boy (formerly, Genius of Telegraphy), clutching his thunderbolts and electrical cables, appears momentarily in the amplifier’s control display. A 30-second warm-up period follows, and then 30 seconds of microprocessor-controlled auto-bias. After 20 minutes of inactivity, the 91E goes into standby mode.

A novel feature of the 91E is its interchangeable transformer block, which is used instead of a multitap transformer. A 4 ohm transformer as well as a 16 ohm one are available as add-ons ($999 each) to replace the included 8 ohm transformer. “We use separate transformers for different impedances because the additional windings in a traditional, tapped transformer cause the signal to deteriorate,” Whitener said.

The 91E uses circuit boards. “The circuitry is much too complex for point-to-point wiring,” Whitener explained. Brands and specifications of the 91E’s capacitors, resistors, transformers, internal wires, RCA jacks, switches, and binding posts are not disclosed.

Setup and first impressions
Unpacking the 91E was like removing a massive jewel from a custom case. Unboxing the pair of 300Bs, each in its own padded container, was a treat. Full documentation accompanied both.

The 91E is massive and required careful maneuvering to fit into my Salamander rack, but two nickel-plated handlebars make moving it a cinch. I plugged in my DAC and turntables and wired up the speakers, but before I could set Golden Boy free to dance around in my room, I had to load my cartridges.

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To use the 91E’s onboard phono stage, Whitener and Western Electric’s Marketing Communications Lead Cobi Boykin supplied me with six pairs of phono termination plugs ($74/pair). Each pair was marked with capacitance for MM (100pF, 220pF, 330pF) or resistive values for MC (100 ohms, 330 ohms, 1000 ohms). Whitener recommended the 100 ohm pair for my EMT TSD15 N Super Fineline. The 330 ohm plug worked best for my Ortofon SPU Classic GE MkII MC cartridge (footnote 3).

Footnote 1: See Bell Labs timeline.

Footnote 2: See Re-Tales #22. Also see Herb Reichert’s May 2021 Gramophone Dreams column, “The Venus Tube” and Peter van Willenswaard’s “In Search of the Perfect 300B Tube.”

Footnote 3: Western Electric offers advice to owners on choosing the proper phono termination plug.

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