NAD 218 THX BEAST!!!

Great amp, and up to the audiophile task for any speaker and any load.
Works fine, zero issues. Cosmetics average, one bend on front UPPER face plate, one binding nut on speaker post missing - banana plugs work fine. Call 402 498 2773 or email, do not text. thx!
From Stereophile review: Specifications Description: THX-certified stereo power amplifier. Rated power: 225Wpc (23.5dBW), 780W bridged mono (28.9dBW) (both into 8 ohms). Frequency response: 20Hz-20kHz, -0.3dB. Slew rate: >100V/µs. Damping factor: >200. Input impedance: 47k ohms in parallel with 700pF. Input sensitivity: 1.5V for rated power. Signal/noise ratio, A-weighted: 120dB at rated power. THD: <0.03%. Dimensions: 19" (483mm) W by 7" (175mm) H by 16.5" (420mm) D. Weight: 49.5 lbs (22.5kg).
NAD 218 THX power amplifier Shipping is $30.

By Robert J. Reina • Posted: May 2, 2004 • Published: Aug 1, 1999
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The story of New Acoustic Dimensions, aka NAD, begins in the late 1970s. The company was founded as a dealer distribution collective to design and market reasonably priced serious high-end gear to cost-constrained audiophiles. By eliminating needless features and focusing manufacturing in low-cost production facilities, NAD has successfully delivered audiophile-quality gear for 20 years at prices little more expensive than mass-market department-store schlock.
Serious design
The 218 THX--designed in the UK and manufactured in China--is the flagship of a series of high-powered basic stereo amplifiers that represent a new design approach for NAD: the marriage of massive power supplies with an amplifier design consistent with the company's traditional goals of performance and affordability. A Holmgren toroidal transformer coupled with a bank of multiple small reservoir capacitors (as opposed to a small number of large ones) endows the amp, claims NAD, with a very low source impedance and the ability to respond very quickly to repeated demands for current. The 218's input/driver stages (operating in pure class-A supplied by its own independent power supply) use current-mode feedback to achieve wide open-loop bandwidth. Three Panasonic output devices are used in parallel for each half of the complementary output stage. There is a servo for DC offset, and the only capacitor in the signal path is a selected film type at the input.

The 218 THX features balanced and unbalanced inputs; via the former, it passes THX certification requirements for power output and input sensitivity. There is also the ubiquitous NAD "soft clipping" button, which the company effectively calls the "party switch." When the switch is engaged, the amplifier filters out the high-frequency edges that squarewaves produce when the amp goes into clipping, and thus protects the speakers from excessive HF energy. During my listening sessions I noticed no difference in sound when this switch was engaged, but as the amplifier puts out 225Wpc into eight ohms (780W when bridged for mono operation!), I'm certain I never approached its rated power limit, even during high-volume peel-the-paint-off-the- tests.

Speaking of current-delivery capability...when I first hooked up this amplifier to my main reference system, I didn't realize that the unobtrusive power switch on the front panel was engaged. As I began to gently plug in the unit's AC cord, a bolt of bluish-gray lightning shot from the outlet into the cord, causing this stunned reviewer to drop the cord and recheck the faceplate of the amp. Nope, it still said NAD, not Krell.

Serious sound
A THX-certified amplifier of this power rating for $1099 is impressive indeed, but how did it sound? On first turn-on, NAD's trademark tonal balance was immediately recognizable: a rich, tubelike, dimensional presentation, most of whose flaws were euphonic or subtractive, and consonant with the musical experience. On well-recorded vocal works, all voices, male and female, had a rich, supple palpable quality, much as one would expect from a more expensive tube amplifier. On Bill Berry's For Duke (M&K Realtime RT-101), the trumpet was reproduced with the requisite blend of blat and burnished metal. The tenor sax solo on "Take the A Train" was naturally throaty and chesty without seeming colored.