Aurorasound VIDA Prima Phono Preamplifier Lab Report

Lab Report

Similar in name only to the original VIDA [HFN Jul '13], the VIDA Prima employs a far simpler, part-active (low frequency)/part-passive (high frequency) RIAA network. The headline differences in performance between the two are as follows: the costlier Vida offers superior input overload margins, a higher output and lower noise via MC, while the VIDA Prima trades this for a wider MM S/N ratio, a much flatter and extended HF response and lower overall distortion. Talking of distortion, this is indeed exceptionally low at ~0.0002% through the midrange, increasing slightly to ~0.001% at the bass/treble frequency extremes [Graph 2, below]. In practice this is of academic interest only as the typical pick-up's distortion will be 1000x higher (re. 5cm/sec).


RIAA-corrected freq. response (L/R, black/red; 5Hz-100kHz) versus output impedance (cyan trace)


Distortion versus extended frequency (5Hz-40kHz) via MM input, re. 0dBV output

Its equalised response is also comfortably beyond that of any pick-up, albeit very slightly 'flatter' on the left than right channel, at ±0.4dB from 100Hz-100kHz and with a subsonic filter of –0.5dB/20Hz down to –6dB/4Hz [see Graph 1, above]. The output impedance is usefully low at 45ohm through mid and treble, increasing to 100ohm/75Hz and 715ohm/20Hz [blue infill, Graph 1]. In its MM setting, the VIDA Prima offers +40.5dB gain (47kohm loading) and a generous 90.5dB A-wtd S/N ratio.

So this is a very quiet MM stage with an input overload margin of 89mV – this represents a headroom of +25dB to accommodate the wildest of vinyl grooves (re. 5mV at 1kHz/5cm/sec). The MC input includes an additional +23.9dB, realising a total gain of +64.4dB, but the A-wtd S/N ratio of 71.3dB is slightly reduced (re. 500µV) and the 5.6mV overload margin is less generous. With a headroom of +21dB (or +19.4dB re. its 0.6mV sensitivity), the VIDA Prima's MC input is best suited to medium- rather than high- or low-output MCs. PM

Input loading (MM/MC) 47kohm / 75ohm & 900ohm
Input sensitivity (re. 0dBV balanced out) 9.39mV / 603µV
Input overload (re. 1% THD) 89mV / 5.6mV
Max. output (re. 1% THD) / Impedance 9.0V / 45-713ohm
A-wtd S/N ratio (re. 0dBV balanced out) 90.5dB / 71.3dB
Frequency resp. (20Hz-20kHz/100kHz) –0.48dB to –0.07dB / +0.12dB
Distortion (20Hz-20kHz, re. 0dBV) 0.00021–0.0011%
Power consumption 4W
Dimensions (WHD) / Weight 250x69x246mm / 2.3kg
Price £1000
Aurorasound Inc
Supplied by: Pure Sound, UK
01822 612449