PHLUX-II correction

The Phædrus Audio PHLUX-II active phono cartridge was developed in conjuction with Pspatial Audio and is the ideal match for needle-drops made for processing in Stereo Lab.

Not only does the PHLUX-II cartridge guarantee excellent tracking, but it also has a very level frequency response: a worthwhile attribute when you are aiming for correct equalisation for the recording characteristic of the record (even if that is only the RIAA standard). There is, after all, little point in aiming for accurate equalisation if the initial needle-drop signal dispays significant frequency-response variations.

Despite the mechanical nature of the PHLUX-II transducer, frequency-response is confined to a variation of ±1dB (ignoring wavelength-loss on inner groves). This is a very good result and is illustrated in the graph above by the red trace.

Digital correction

Nevertheless, ±1dB is just perceptible - especially when it is a monotonic 2dB drop as shown in the graph. The result is a very slightly "warm" tonal balance. So, before applying recording-characteristic equalisation, it is possible to correct this very slight response anomaly in software. The black trace indicates the corrected response which brings the variation of the PHLUX-II frequency-response to less than ½dB; a result below accepted levels of perceptibility.

The combination of PHLUX-II and Stereo Lab offers a solution with which to extract the information captured on the original record with forensic accuracy.

PHLUX-II correction is engaged within the PHONO EQ Preferences tab.


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