I'm working around the Boss DS-1 in these days.
I emulated the two buffer, input and output, separately, with the a pc software.
The input buffer is nothing that a buffer. It works fine, it has a bass cut far enough from a guitar frequencies.
The output buffer works about the same, with slightly less bass cut, but even with a bit of volume loss, probably imperceptible.
(I'm searching a verified Boss DS-1 veroboard layout. The one on Guitar FX seems had caused some issues to someone, and it's not completely authentic.
I found a bufferless layout on Sabrotone, so I thought to add input and output buffer, in case).
I build pedals