McIntosh 275 Mk V and NOS tubes

Evidently McIntosh has introduced a new version of its renowed Mc275 model, the Mk V variant. The mark V is the EU RoHS directive compliant product, i.e. lead and other "hazardous substances" free. In addition, Mk V finally eliminates strip speaker connections and has proper speaker connections, so you don't have to re-terminate your speaker cables. Also gone is adjustable sensitivity on unbalanced input.

I started saying that "evidently" because I have not yet seen any mention about mark V on McIntosh Web-site. However, I do know it exists as I've been happy owner more than 2 months. I reviewed Mc275 for one hifi-publication and was so impressed that I replaced my previous power amp Mark Levinson 334 by review sample.

Mc275 is everything than other reviewers have said and then some. I found Mc275 in my gear to be more transparent and more silent than ML334, ideally suited for kind of music I listen predominantly, i.e. acoustic jazz. The Mc275 is the quietest tube power amp I've heard, bar one. What Mc275 left me wanting vis-a-vis ML334 was that feeling of absolute authority and control. Guess I have to upgrade next to Audio Research Reference 110 in order to get Mc275's life-like performance and ML334's majesty.

I my review I stated that Mc275 did not responded much to NOS tube rolling, ie. my experimentation with NOS 12AX7A tubes did not demonstrate that much difference. I tested Philips Holland Pope 12AX7 1959 (Upscale Audio Platinium Grade, exactly same tube as Amperex Bugle Boy Holland 12AX7) and Sylvania 1961 Vintage 12AX7 1961 (Upscale Audio Platinium Grade).

Now I have to re-state my findings, reason is that I replaced stock KT88 tubes by original Svetlana, cryo treated KTR88s, purchased from Watford Valves. To cut the long story short, if you want to know what your Mc275 is capable for, try cryo treated Svetlana winged-C KT88s. Combined with Sylvania 12AX7s they produce truly breath-taking music. Moreover, I installed Herbie's Audio Lab's nickel alloy tube dampers for all small12xxx tubes and KT88 power tubes, which further tightened low registers and took care of tiny amount of microphonic haze and fuzziness. Additonal upgrade I found beneficial was Kimber Kable's top-of-the-line power cable Palladian PK10 (in my tests much better choice than Nordost Shiva or Siltech SPX20/30) and a proper platform (my Mc275 floats on Aurios Pro bearings, which reside on top of Symposium Svelte platform.

I ordered from Wafford Valves cryo treated NOS Mullard 12AT7 to replace stock tubes, but even without them I can honestly say that Mc275 with upgarded tubes causes long, long listening sessions. Phenomenal "breath-of-life", holographic imaging and transparency.