Adding bridge rectifier to ADC input
Don't bother with the rectifier, just move the whole signal up into the ADC's range.
Like this:



simulate this circuit &ndash; Schematic created using CircuitLab

C1 lets your audio circuit &quot;float up&quot; so that is is no longer +-5V but rather is entirely above 0V.
R1 and R2 move your audio to be &quot;riding&quot; on a 2.5V offset.
R3 plays together with R1 and R2 to reduce the audio from 10V peak to peak to just 5V peak to peak.

If I haven't bungled it somewhere, that'll reduce the level of your audio to fit your ADC and move it to where the ADC can properly sample it.

The bridge rectifier would &quot;chop off&quot; a part of your audio signal.  Nothing between -0.7V and 0.7V would get through.  Quiet bits of your music would be &quot;lost&quot; to the ADC.