McIntosh Laboratories is one of those select companies that have achieved legendary status among audiophiles and discerning listeners. Established in 1949, McIntosh was one of the founders of the high-fidelity audio industry, along with companies like Marantz, Harman Kardon, Fisher, H. H. Scott, Quad, Garrard, Acoustic Research, Tannoy and others. From the beginning, McIntosh components were designed and built to extremely high standards.
• Read more stereo amp reviews from the likes of McIntosh, Krell, Audio Research, Quad, VAC, VTL, Mark Levinson and many others.
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• Check out this Billy Bags rack made JUST for McIntosh equipment.
• Read Brian Kahn's McIntosh MC501 power amp review here.
The MC275 vacuum tube stereo power amplifier exemplifies the McIntosh design philosophy. It was originally introduced in 1961 and quickly established itself as one of the standard-setting amplifiers of the time. The original version was discontinued in 1970. In 1991, the Gordon Gow commemorative limited edition was introduced as a tribute to the late McIntosh president. After the first re-issue, the MC275 has come and gone over the years with various iterations in circuitry, control layout and appearance, and is now back in production.
The MC275 (suggested retail price: $4,500) is a vacuum tube amplifier that delivers 75 watts per channel into eight, four or two ohms, or 150 watts in bridged mono mode, via four KT-88 power tubes. The MC275 offers RCA and XLR balanced inputs, gold-plated screw-type speaker terminals, a stereo/mono mode switch and an on/off switch. A key element of the MC275's performance is its Unity Coupled Circuit transformer design. Without getting too technical, this topology uses three transformer windings (two primaries and a secondary) instead of the usual two (primary and secondary). The two primary windings are wound together closely, a design claimed to reduce distortion and noise across the entire frequency range. Made in the good old USA in Binghamton, New York, the MC275's build quality is extremely high, with a stainless steel chassis, ceramic tube sockets, gold-plated screw-type input jacks and heavy transformers that make up the bulk of the amplifier's hefty 67-pound weight. Its appearance is delightfully retro (although it must have been cutting-edge in 1961), thanks to its polished stainless steel-and-matte black styling, Old English McIntosh logo font and the soothing glow of its vacuum tubes visible from inside the perforated black tube cage.
The MC275's sound is richly detailed and inviting, with absolutely no trace of harshness or stridency. Although it does not deliver state-of-the-art resolution and detail, especially in the upper midrange and high frequencies, the amplifier offers an expansive soundstage with excellent imaging, and has a smooth tonal balance from bass to treble. The MC275 sounds powerful and dynamic, although it can be bested in low-frequency authority and articulation by other high-end solid state and other vacuum tube amplifiers.
Competition and Comparison
You can compare the McIntosh MC275 amplifier against some of its competition by reading our reviews for the Melody SP3 and the PrimaLuna 3 and 4 amplifiers. There is also a great deal more information available in our Amplifier section. Also, check out our McIntosh brand page for more information on the company.
The problem with reviews of tube amps in general, and even more so with lower-powered tube amps, is that the so-called weaknesses are totally speaker dependent. Weak base won't be nearly as weak on an amp with high impedance in the bass frequencies. Weak base won't be nearly as weak when speakers have high sensitivity. Speakers with powered woofers, for example, often have rapidly rising impedance at low frequencies that will "fix" a lot of the shortcomings in SE triodes, not to mention push-pull tetrodes and pentodes. Currently, I have an MC275 hooked up to Avantgarde Duo Omegas, and the bass is as good as with a solid state amp. Now, these speakers are EXTREME cases (18 ohms, 107dB sensitivity) with a built-in, less-than stellar, powered woofer, but my point stands. When I use the MC275 with 6 ohm, 87dB sensitivity speakers, the bass is as described in this review and vastly bettered by a 400 watt Sunfire (are you surprised?). As to high frequency extension, there's a fine line between peaked-up treble and honest treble. And there's a fine line between true transient response and overshot/undershot transient response, which delivers etched sound and sonic images that are the aural equivalent of over-sharpened still images: impressive initially, but soon unappealing, and ultimately intolerable. When I upgraded the Duos to Duo Omegas, the solid-state BAT VK220 amp that I had loved suddenly became too edgy. The MC275, while not the last word in side-to-side and up-and-down imaging, is FAR more musical. And the imaging isn't bad either. Bottom line: Power amp reviews are a great place to start; but unless they are done with speakers a lot like yours, you can't bet your paycheck on them. Those who live in big metro areas, with plenty of audio salons to browse, can audition amps and even take smaller speakers with them to test -- I've done it myself. But others of us are forced to buy eBay stuff that we can sell if it doesn't work out. You New York / LA / Chicago types should consider yourselves lucky in that regard.