[GeneS]

I have a pair of preamp outs on my Candela preamp.
What are they for?

[Phil A]

https://www.ooberpad.com/blogs/audio-video-tips/what-is-a-pre-out-and-what-are-its-uses-a-complete-guide?srsltid=AfmBOoqJp8Dgxfg2163QlkrMhi4ru4GY1WQjoL9Lulisye-WxxnWkBaM

[Delta77]

That is where you plug your amps into.
Connect the PREAMP (rca) outputs to the AMP's (rca) inputs.
Usually one set will run the Front Speaker's amp, and the other set will run the subwoofer's amp/amps. 

By use RCA cables, the sources (TT, Streamer/DAC, CD player) are plugged into the Preamp for Volume control and switching sources, then the preamp is plugged into the amp.

[klaus@odyssey]

Hey Gene,

Guessing that you're asking about the horizontal connectors...2nd outs for either biamping or subs

[GeneS]

Thank you, my friend
And thank you to my other friends who replied who I haven’t met yet!

[justjed]

I use the second pair of outputs for a headphone amp, mostly. Sometimes I biamp my system. There are many uses for extra outputs.

[opnly bafld]

Or a pair Y cables can be used if your pre has 1 output.