In the halcyon days of the Mesa Baron, certain audiophiles used to get their starchy-white knickers into a terrible twist of cinnamon-streaked and irritated strangulation. Pentode or triode; how much of each; ⅓, ⅔ or full-boat? Adjustable NFB - but where to set it? Adjustable bias - on the mark or slighty under or over? Then came the final death knell in the guise of the Tri-Tube Mod: 5881s, KT88s or E34Ls. Which one to pick; and of what vintage and make, pray tell? These audiophiles, in complete denial of their collective angst, argued that if one of these numerous but confounding settings and options was right, all others had to be patently wrong. And if wrong they indeed were -- remember, these folks believed in the one-size-fits-all gospel of the absolute sound -- then why the heck include 'em? It didn't dawn on them that their right could be another's wrong. And you better didn't dare proposing a favorite rather than correct setting. The audiophile police would have charged you with sedition from the rank'n'file corps. Besides which, how much more soddingly wrong could it have gotten? We were faced with a boogilicious guitar amplifier firm possessed of the ill-advised, completely unseasonal gumption to design a bona fide High-End hi-power tube amplifier. What by the sanctified overtones of Stradivarious could Telecaster overdrive distortion-crunch possibly have in common with virginal audiophile purity?

These were the kind of colorful complaints which that feisty old blue-blood of an amplifier had to elude time and again. I should know; I was working for Randy Smith at the time. His whole heretical concept of adjustability, of system optimization, of calibrating the sound to the end user's liking -- of messing with the absolute sound -- was either too revolutionary or retro for most high-enders of the day. To them, the Baron was a platypus. Neither duck, gerbil or fish, it just didn't fit their hi-falutin' notions of proper High-End behavior. That salad fork goes over there, dear...

Enter EveAnna Manley's Neo-Classic SE/PP 300B monos. Do you believe that the Baron was screwed up beyond recognition, suffering an identity crisis worse than Jason Bourne's ten passports? Hey, at least it had the damn decency to stay in one class of operation: push/pull. Besides offering selectable NFB up to 10dB, the Neo-Classics fall from grace by also coming from a firm with celebrated professional gear (what could they possible know about proppa HiFi?) and -- far worse -- incorporate single-ended and push/pull operation in a single chassis, selectable on the fly with the, good grief, casual flick of a switch. Hell and damnation, the Anti-Christ's arrived. The Neos' single redeeming feature over Randy's beast? The use of the audiophile-approved 300B direct-heated output triode in Russian Electro-Harmonix guise. Okay, that just turned these renegades back into JC, albeit with offspring by the Magdalene and thus oh-so-mortal and fatally wounded.

Jesting aside, the Neo-Classic could only have come from an outfit with a fresh attitude, one that doesn't view music reproduction as a life-and-death sentence of grueling term papers, of Harry Pearson-style advanced philosophy. Rather, it invites you to experiment with different topologies, feedback settings, bias points and impedance-matching transformer secondaries to select what sounds best to your ears. Hence only read on if this concept of fun in audio doesn't strike you as anathema. Be prepared to engage different NBF settings and toggle between parallel single-ended (for about 11 watts at 5dB of feedback) or push-pull (24 watts @5dB). Be prepared, too, to make up your own mind and trust your own opinion. Scared? Then plunk down for an all-in-one rack system and be done with it. Adios.

With a 6SL7 input, 6SN7 driver and twin 5U4 rectifiers, the Neo-Classic is an all-valve affair, 41 lbs heavy and 11" deep, 8.5" wide and 9" inches tall - including projecting controls, footers and terminals. Input sensitivity changes with circuit topology, from 450mV in push/pull to 750mV in single-ended. Ditto for S/N ratio and dynamic range, the former marginally higher in SE, the latter nearly 6dB better in P/P. The amp works in Class A regardless but output power and damping factor are naturally variable with feedback. That is adjustable via a rotary knob in 1dB increments from 0 to 10. Bias adjustments require a voltmeter to take a reading via the provided test jacks adjacent to the NFB control [left]. The requisite twin trim pots live between the output tubes [right].

The mains power switch is mounted on the rear but doesn't require shutting down to alternate between SE and PP mode. The audio signal can be interrupted via the front-panel mute/operate toggle while hoisting the SE or PP flag under signal. It's as simple as changing the neighboring toggle from up to down or back again.

An impedance selector next to the WBT terminals offers 4-8 and 12-20-ohm settings while the integral footer rails terminate in softened ends, to make both sharp and pointy things plus their ubiquitous protector discs redundant. My amplifiers arrived fully preconditioned as they were Manley's dedicated traveling review loaner pair. They were gussied up in a high-polish stainless steel chassis with black accents and fascia, the older cosmetic styling no longer available. The current vogue features a more subdued two-tone appearance [image to end of review].

The amps are now trimmed out in original blue-grey faceplate, knobs and feet to accent the black wrinkle powder-coated chassis. It's an attractive, open-architecture slim line look with easy accessibility of the various tuning options. From a conceptual perspective, the cross-denominational spirit of the Neo-Classic monos allows its owner to shift from stiff damping factor and higher-power/lower-THD on one hand to zero-correction/low-control, full-bore saturated triode glory on the other - and anywhere in-between, with as many additional hands as Shiva Nataraj, the eternal dancer of Hindu lore. This might challenge assumptions and, perhaps, reveal that some of the dreaded heathens 'in the other camp' have religion, too. Speaking of pantheon, the deities at Manley have titles like Slide Rule Jockey [Mitch Margolis], Whine Tester [Hutch Hutchison], Oiler & Boiler [Humberto Rodriguez], Chassis Fulfillment [Baltazar Hernandez], Valve Grinder [Paul Fargo] and Pit Boss [EveAnna Manley]. Doesn't this conjure up a whiff of pagan worship? Where's the bloody Grand Inquisition when you need it?

No matter how you slice it, the Neo-Classic is a ballsy proposition. Needless to add, it's from a gal widely known throughout the industry for her motorcycle chops, indicating that she's got them round prune thingies, too. Detractors of this type of freedom will naturally opine that an output transformer capable of supporting both P/P and SE operation must be less than optimized for either and thus somehow flawed. It's an argument I found myself sensitive to as well. This mandated firing off an e-mail to EveAnna, to discover how this very unusual feat had been accomplished.

Based on an outrageous and original idea by David Manley first excecuted in Manley Lab's 'Compact' and then 'Retro' versions of this concept during the mid-'90's, today's switchable Neo-Classic SE/PP monos were the result of 6 months worth of extensive real-world engineering by Mitch, he of the slide ruler, to turn an interesting but also somewhat bizarre notion -- let's see what happens if we cross a porcupine with barbed wire -- not just into a curious accident but bona fide, refined HiFi product.
As EveAnna vouchsafed, this took some serious sweat equity and creative chops. Margolis addressed the driver stage to offer enough current for swinging even exotica like KR Audio's VV30B. Power bandwidth was expanded over the original models, idle plate dissipation reduced to extend tube life. Adding extensive pi filtering for the filaments suppressed power supply ripple by a claimed 40dB for much lower operational noise floor while the revised chassis size allowed incorporation of a much beefier power transformer to guarantee plenty of headroom for elimination of mechanical noise. A new cross-feed bias feature isolates individual tube adjustments from affecting the other valve while the amount of boutique coupling caps has been increased and upgraded to Bas Lim's more robust Multicaps®. This dramatic overhaul has apparently much improved the test bench performance of this radical design and banished serious THD aberrations of the original models. About that necessary output transformer trickery, Mitch now had this to say: