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For the past several years, rather than let an active phono preamplifier do all the work, I've preferred to use step-up transformers with low-output moving-coil cartridges. There are some good active stages out there—the Linn Linto comes to mind, as well as the Naim Prefix and the MC phono boards for the DNM 3-C preamplifier—but it's my experience that trannies let the music breathe a little better.

But because I'm not an engineer, and because the old-fashionedness of the transformer approach at times leaves me feeling somewhat…

Description: Tubed stereo preamplifier. Tube complement: five 7DJ8/PCC88. Phono inputs: 2. Line inputs: 2 balanced, 3 unbalanced. Tape loops: 1. Outputs: 1 balanced, 1 unbalanced. Input impedances, phono: 47k ohms, moving-magnet; 3, 6, 12, or 40 ohms, moving-coil. Output impedance: 600 ohms. Line-stage gain: 14dB. Phono-stage gain: 50–80dB. Signal/noise ratio: 68dB phono (ref. 2.4mV), 90dB line (ref. 1V). Frequency response: 20Hz–20kHz, –0.3dB. Distortion: <0.1% at 1kHz, 3V output. Phase-inverting: No. No, no, no.
Dimensions: 19" (485mm) W by 5.25" (135mm…

Analog Sources: Linn LP12 turntable, Linn Lingo power supply, Linn Ekos tonearm; Rega Planar 3 turntable, Rega RB-300 tonearm; Miyabi 47, Linn Akiva, Lyra Helikon Mono, Linn Adikt, Rega Elys cartridges; Audio Note AN-S2, Tamura TKS-83 moving-coil step-up transformers.
Digital Sources: Naim CD5x CD player, Linn Unidisk SC universal player.
Preamplifier: Fi.
Power Amplifiers: Lamm ML2.1, First Watt F2.
Loudspeakers: Quad ESL-989, Lowther PM6As in Medallion horns.
Cables: Interconnect: Audio Note AN-Vx, Nordost Valhalla. Speaker: Audio Note AN-…

The EAR 912's phono stage offered gains of 50dB, 44dB, and 38dB in MM mode, depending on the position of the front-panel gain switch. The corresponding figures for MC operation were 19dB higher. The MM input impedance was 43k ohms at 20Hz, this increasing slightly to 50k ohms at 1kHz and 47k ohms at 20kHz. With the phono input set to MC and 40 ohms, I measured an input impedance of 422 ohms at 1kHz, this decreasing to 117 ohms at 20Hz and 378 ohms at 20kHz. The phono input preserved absolute polarity.

Fig.1 shows the 912's phono-stage frequency response,…

Description: Solid-state two-channel amplifier. Maximum output power: 400Wpc continuous into 4 ohms (23dBW). Input impedance: 10k ohms, unbalanced, 20k ohms balanced. Output impedance: 0.08 ohm at 7kHz. Frequency response: 5Hz–45kHz, –3dB. THD: <0.007% at 1kHz up to 400Wpc, <0.03% at 7kHz up to 400Wpc.
Dimensions: 17" (435mm) W by 7" (180mm) H by 16" (410mm) D. Weight: 46.5 lbs (21.1kg).
Serial Number of Unit Reviewed: A0000483.
Price: $4990. Approximate number of dealers: 50.
Manufacturer: Halcro, Wayville SA 5034, Australia. US distributor…

Analog Sources: Linn LP12 turntable, Naim Armageddon power supply, Naim Aro tonearm; Miyabi 47, Linn Akiva, Incognito Shibui cartridges; Tamura TKS-83 moving-coil step-up transformer.
Digital Sources: Naim CD5x, Ayre CX-7e CD players; EMM Labs CDSD2/DCC2 SACD player.
Preamplification: Audio Note M3; Linn Linto phono preamplifier.
Power Amplifiers: Lamm ML2.1 monoblocks.
Loudspeakers: Quad ESL-989, Audio Note AN-E Lexus.
Cables: Interconnect: Audio Note AN-Vx, Nordost Valhalla. Speaker: Audio Note AN-SPe, Nordost Valhalla. AC: JPS Labs The…

As with all amplifiers that use a switching output stage, examining the Halcro Logic MC20's performance on the test bench was complicated by the presence of RF energy in its output. Unless this energy is filtered, you can never be sure that you're not actually measuring the interaction between the RF content and the test gear instead of the absolute performance of the amplifier under test. (For a discussion of this subject, see my "Measurements" sidebar accompanying Robert Deutsch's review of the PS Audio GCC-100 amplifier in January.)

Fig.1, for example,…

The $4995 Halcro Logic MC20 is a lesson in stereotypes defied. It demonstrated that pretty much everything I ever assumed I knew about digital amplification is wrong.

My tastes as an audiophile lean toward the simple. The more direct and simple the connection between the original musical source and my eardrums, the happier I tend to be. I love the simplicity and elegance of analog transducers and step-up transformers converting mechanical vibrations into moving electrons in a way that I find direct and easy…