Low-level signals travel across short lengths of Audio Note AN-C interconnect cable, which is a shielded copper Litz type, and the output trannies' secondary windings go straight to the output board, with a pair of XLRs for balanced connection and two pairs of RCA jacks for unbalanced use. Sockets for the five dual triodes all appear on the same neat board, and two narrow sub-boards in front contain the volume and balance potentiometers, plus a motor for the former and the chips and other parts for a basic remote-control system. An enameled metal shield keeps the power supply on the right from messing with the phono and line amps on the left. The M2B's interior is a much tidier place than those of the earliest Audio Note UK preamps, with a neater and sturdier chassis in particular. DC for the various tube heaters is conditioned with separate solid-state regulators, each done up with nice-looking heatsinks. Between them is a passive RIAA equalization circuit.Įven further upstream, the M2B's power supply shares a family resemblance with those of other Audio Note products: It uses a rectifier tube (6X5WGT) for the rail voltages, and a traditional pi filter centered around a 20-Henry choke smooths the power. The phono input sees a cascoded 6DJ8 and 12AX7A, and the output is a 12AU7A. The phono preamp comprises three dual triode tubes, split in this instance so that one half of each tube works for the left channel, the other half for the right. Upstream, each channel of the M2B's line section uses a single 6922 dual triode tube (footnote 1), the two halves of each tube combined as a paralleled common cathode amplifier their output is loaded by the primaries of the aforementioned output transformers (one for each channel), with separate secondaries for balanced and unbalanced output. Audio Note looks at feedback the way GreenPeace looks at tuna nets. It is, as the word indicates, a near perfect transformation of one voltage/current relationship to another, with minimal loss and distortion of the passing signal content.' Consider also that an output transformer is a means of keeping output impedance low without additional active circuitry or, even worse, feedback. a correctly designed interface transformer does not. Resistors and capacitors are imperfect in the sense that they all alter the relationship between amplitude and frequency. That's something Audio Note has been doing for a number of years, beginning with their top-of-the-line M10.Īs the company's Peter Qvortrup puts it, transformer drive 'linearizes the entire dynamic envelope of the music passing through the preamp. Arguably, though, the M2B's greatest design distinction is that it speaks to the world through a pair of output transformers, just like a tube amp.

The M2 has come up for redesign, resulting in a product that not only nips at the M3's heels but comes close to tying the race: the M2 Balanced, or M2B.Īs its name implies, the M2 Balanced can drive the balanced inputs of any amplifier so equipped (although it isn't designed for balanced throughput: all of its signal inputs are single-ended). Now the Audio Note designers have worked their way back through their preamp line-which, incidentally, peaks out at the mighty M10 ($40,000 without phono: go ahead and wince). Then came the very upmarket M3 ($7500 with phono), which took all those strengths and presented them with a level of musical ease and rightness I'd never heard from a preamp before. I tried the somewhat upmarket M2 ($2695 with phono), which sounded like a more refined version of the M1. (Newcomers, please don't wince: That's awfully cheap for what it was.) And the M1 cost only $1250 at the time, with phono stage. The first time I heard an Audio Note preamp was seven or eight years ago, when I sampled their entry-level M1-a refreshingly musical thing that brought the same kind of color and drama to preamplification that Audio Note's more famous products brought to the driving of speakers.

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