I've found a few interesting things while ripping all my SACDs to 88/24 PCM, mainly that DSD digital levels can be all over the place. Some have to be ripped with 0dB in order not to overload as 88/24 PCM, some can take +6dB of boost, most are in between.
Among the strangest is the 1999 single-layer, nonhybrid Sony SACD of Thriller (Michael Jackson) -- for that one, even with +0 dB boost, there are still some digital 'overs' ,on three tracks (The Girl is Mine, Beat It, Billie Jean), when converted to 88/24. This is the only SACD of mine so far (out of a few dozen) that this is true for.
chain is Pioneer BDP-80 ethernet out --> iso2dsd (Raw iso output) --> Foobar2k w/foo_input_SACD (88khz PCM output, Multistage 32fp DSD2PCM mode) --> wav-->flac (output is always 24 bits)
Checking the 'Log Overloads' option and using View--> Console when using foobar_input_sacd is a convenient way to document overloads.
Replaygain scanning of the original DSD64 track of 'Billie Jean' embedded in the iso says it peaks at +1.062; converting to PCM at the above settings produces 35 'overs', all within the first 18 seconds.
Changing PCM output to 44 kHz reduces the number of overs to 4;, changing it to 176 kHz produces way more than 35, so I assume it's an effect of ultrasonic noise.
Using the 88kHz output setting with Direct 32fp 30Khz lowpass DSD2PCM mode reduces overs from 35 to 33, suggesting that ultrasonic noise between 22 and 30khz is the main culprit.
I've tried fiddling with drastically reducing preamp settings in foobar, and with changing f2k output device settings (DS vs DSD vs WSAPI), changing output format to 32 bit where possible, but they seem to have no effect on the level of the signal going into the converter, so nothing changes.
It's curious but not disastrous. The overs are brief and not extremely numerous, unlikely to be audible, on the three tracks.
Among the strangest is the 1999 single-layer, nonhybrid Sony SACD of Thriller (Michael Jackson) -- for that one, even with +0 dB boost, there are still some digital 'overs' ,on three tracks (The Girl is Mine, Beat It, Billie Jean), when converted to 88/24. This is the only SACD of mine so far (out of a few dozen) that this is true for.
chain is Pioneer BDP-80 ethernet out --> iso2dsd (Raw iso output) --> Foobar2k w/foo_input_SACD (88khz PCM output, Multistage 32fp DSD2PCM mode) --> wav-->flac (output is always 24 bits)
Checking the 'Log Overloads' option and using View--> Console when using foobar_input_sacd is a convenient way to document overloads.
Replaygain scanning of the original DSD64 track of 'Billie Jean' embedded in the iso says it peaks at +1.062; converting to PCM at the above settings produces 35 'overs', all within the first 18 seconds.
Changing PCM output to 44 kHz reduces the number of overs to 4;, changing it to 176 kHz produces way more than 35, so I assume it's an effect of ultrasonic noise.
Using the 88kHz output setting with Direct 32fp 30Khz lowpass DSD2PCM mode reduces overs from 35 to 33, suggesting that ultrasonic noise between 22 and 30khz is the main culprit.
I've tried fiddling with drastically reducing preamp settings in foobar, and with changing f2k output device settings (DS vs DSD vs WSAPI), changing output format to 32 bit where possible, but they seem to have no effect on the level of the signal going into the converter, so nothing changes.
It's curious but not disastrous. The overs are brief and not extremely numerous, unlikely to be audible, on the three tracks.