Is it better to use single end from Yggy to Woo and let the Yggy do the conversion?
Or use the balanced and let the Woo do the conversion?
Use the yggy balanced out.
It has the better sound.
A bit louder, and larger sound.
If you can't hear the difference,
You can either blame your setup,
Or,
Take it as a plus to not have to keep improving your setup since there no difference for you.
Either way is fine.
Otherwise, it is already been stated long ago in the yggy threads,
that the balanced output are better.
If your system is very resolving you will hear quite a difference.
So let the amp get the balanced and do what is has to do.
Those woo setups are nice.