Above: Reference, Input 10 kHz Test Tone (192 kHz 24 Bit Audio File)
Conditions: input level -0.1 dB vs. digital full scale, AIFF uncompressed file with 10 kHz, 24 bit test tone (note: the FFT Cosine window used causes broadening of the peak, the reason why the peak doesn't reach full scale on the display. This is normal behavior for a windowed FFT.)
Above: After applying Pure Vinyl Precision 64 Bit RIAA and Pure Vinyl's zero-phase-shift "rumble" (high pass) filter
Compare with the first spectrum; this shows that Pure Vinyl's 64 bit RIAA (and rumble) filter contribute no distortion. (Pure Vinyl's rumble filter cutoff frequency is adjustable from 14 to 70 Hz.) 13.7 dB gain applied to signal to bring to full scale (RIAA curve attenuation at 10 kHz is 13.7 dB).
Above: Reference, Input 100 Hz Test Tone (192 kHz 24 Bit Audio File)
Above: After applying Pure Vinyl Precision 64 Bit RIAA and Pure Vinyl's zero-phase-shift "rumble" (high pass) filter
Compare with the previous spectrum; this shows that Pure Vinyl's 64 bit RIAA (and rumble) filter contribute no distortion. 13.1 dB attenuation applied to signal, to keep within full scale (RIAA curve gain at 100 Hz is 13.1 dB).