Ortofon MC Anna Diamond Cartridge Lab Report

Lab Report

Much is made of the concentrated magnetic flux of the MC Anna's high-end rare-earth magnet, and while this does not significantly boost output – the limited number of turns in the OFC 'moving-coil' reflected in its 6ohm impedance – the low 207µV (re. 1kHz/5cm/sec) of this '2019' version is still +1.2dB higher than the original MC Anna [HFN Oct '12]. Instead, it's the uniformity of this magnetic field, and symmetry of the cantilever/coil suspension, that deals this pick-up's trump card: the superb balance between lateral (L+R) and vertical (L-R) responses [Graph 1, below] and lateral and vertical distortion profiles [Graph 2].

This quality fundamentally separates the MC Anna from Ortofon's other flagship – the MC Windfeld Ti [HFN Jan '18] – which is notably asymmetrical. The matching of these in- and out-of-phase responses promises sharp stereo imagery over a broad soundstage while the 'lifted' +1.5dB presence (and +2dB treble), will lend it just a hint of extra bite. The diamond cantilever also extends the HF resp. from –4dB/20kHz (boron) to –0.9dB/20kHz here. THD remains low at <1% through bass and midrange up to 3kHz (re. –8dB re. 5cm/sec), the increase thereafter simply a reflection of the pick-up's extended HF.

The MC Anna also has a very low compliance (10cu lateral and 7cu vertical) to complement its high 16g bodyweight, so 12g+ effective mass arms are ideal. Tracking performance for the 'diamond' does not quite match the 'boron' MC Anna, but then the former has a reduced 2.3-2.4g recommended downforce (from 2.6g). In practice it held on to the 75-80μm test tracks before letting go on the +18dB groove modulation (315Hz lateral cut, re. 11.2μm) where THD increased to 4%. PM

1219orto.lab1

Frequency response curves (–8dB re. 5cm/sec) lateral (L+R, black) versus vertical (L–R, red)

1219orto.lab2

Lateral (L+R, black infill) and vertical (L–R, red) tracing and generator distortion (2nd-4th harmonics) vs. frequency from 20Hz-20kHz (–8dB re. 5cm/sec)

Generator type/weight Moving-coil / 16g
Recommended tracking force 2.3-2.4mN (2.35mN)
Sensitivity/balance (re. 5cm/sec) 202µV / 0.38dB
Compliance (vertical/lateral) 7cu / 10cu
Vertical tracking angle 26 degrees
L/R Tracking ability 80μm / 75μm
L/R Distortion (–8dB, 20Hz-20kHz) 0.5–11.2% / 0.3–11.5%
L/R Frequency resp. (20Hz-20kHz) –0.4 to +2.1dB / –0.4 to +3.7dB
Stereo separation (1kHz / 20kHz) 35dB / 30dB
Price £7250
COMPANY INFO
Ortofon A/S
Denmark
Supplied by: Henley Audio Ltd, UK
01235 511166
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