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The two bottom fans had me a bit skeptical too. In use however they were audible only with the ear very close to the amp. Without signal one can merely make out a very faint whir but not beyond one meter. That's about the same distance where the meter reading becomes obscure. In toto this is functionally a rather bareboned integrated but one look at the actual dimensions and then heaving the machine airborne quickly suggest that all isn't quite as plain as that.

The luxo chassis itself certainly doesn’t come close to putting 40kg on the scale. I was still at hello though to read that the internal toroidal transformer is good for 2.000 watts.

While it went a way to explain the weight, it raised new questions. At an admittedly beefy 175/330wpc into 8/4Ω, I know plenty of amps which get by fine with significantly smaller power supplies. Remembering the fans I wondered whether B.M.C.’s Amp C1 operated in toasty class A?

This the company’s Manfred Pfennig resolutely refuted. He simply insisted that given their power ratings the 2.000-watt iron was essential and that under peak conditions the amp was actually good for 900 watts. Since electrical circuitry always operates with losses, 2KW were far from excessive I was told. Additionally B.M.C. favors extremely short recovery times. The high number of very fast and stable but small power-supply capacitors draws a lot of current on demand.

The generously dimensioned PSU also avoids 100Hz supply ripple during capacitive recharges. Though their power supply was certainly important, I was told that the innovative load-effect-free LEF circuitry separating voltage and current gain stages was even more so. Here I confess to fading out. If you wish to learn more on the subject, access the relevant PDF on B.M.C. Audio’s website. I did retain that the Amp C1 is built up fully dual differential, eschews global feedback and prefers balanced sources. Also that the engineering personnel behind the firm is far from newly minted but industry veteran caliber and as such champions certain proprietary solutions.

In passing I also learnt a bit on their electronic volume control which they call discrete intelligent gain management or DIGM for alphabet soup. This describes a variable gain output stage which avoids the conventional standard of attenuating the incoming signal voltage which then gets applied to a fixed-gain output stage. DIGM varies the circuit’s amplification factor directly over 66 steps [PS Audio has a similar concept called gain cell – Ed.] In use I ran the display between 30 and 40. Considering that the C1’s voltage gain at 40 essentially equals zero to act as a pure current buffer into the loudspeakers, that was quite sobering.

With nothing left to report on externals or internals, we move on to der klang. The martial cosmetics and realization that a good part of the total 40kg mass was taken up by the 2kW toroidal transformer had me under automatic expectations that the amp would instantly surge forward like a freight train. So much for assumptions.

If you’ve previously clawed your way up the hifi food chain you already know that up to a certain level one keeps hearing more – more detail, more bass control, more holography. But eventually this stops. If one keeps pressing upward undeterred into even higher price/quality strata one often believes to eventually be hearing less. That’s not because one actually hears less detail etc. It’s that acoustic data is structured more clearly, better assigned to musical events and soundstage position. One no longer hears more. One hears with more accuracy.