Whats in your second system?

I also have a very simple but nonetheless pleasant tertiary system in the bedroom:
Wharfedale Diamond 9.0 speakers
Ava Maestro 50 amplifier (with optical input)
Chromecast Audio as an optical digital source.
The amplifier is a very small and completely digital affair with an auto on/off function as its main virtue. It sits out of sight, tucked away in a wardrobe. It is turned on by a signal from the Chromecast, and is usually turned off by the TuneIn sleeptimer on the Chromecast. Unfortunately Chromecast does not have a native sleeptimer - that functionality has to come from the app for the streaming service. TuneIn has one, but Spotify e.g. does not. The amplifier is about 2x25 watt, and that is enough, but only just. I also tried it with my (insensitive) Harbeth P3ESR speakers, but it was not really powerful enough to drive those well. But I am quite happy with the more efficient Wharfedales - they are mostly used to listen to late night talk radio. But even for some casual music they are by no means offensive.

My current second system is a ridiculous hodge-podge of leftover components that makes no sense (the digital front is is 10x the speaker price, so taking the full Linn approach here), but hey, if you've been an audiophile long enough ... 

Accuphase E-406V integrated amp
Emm Labs DCC2 DAC / Preamp
MacIntosh MVP-881 Blu Ray
Usher BE-718 Speakers
Purist Aqeuous, Silversmith cables

Its an AV system, but sounds pretty decent for where its set up (not an audiophile approved location)

My bedroom system:

Speakers:
Kef LS50s

Amplification:
Creek Evolution 100a Integrated Amp
     w/ Ruby DAC module

Sources:
Chromecast Audio (digital in to DAC)
Old Pioneer CD/DVD player for CDs
TV / DirecTV
FM Tuner built into Ruby Module
Occasionally move a VPI Nomad turntable to this system but it doesn’t live there normally due to space limitations. 

Wanted to try the LS50s after reading all the amazing reviews and loved the small footprint and great flexibility/connectivity of the Creek w/ DAC module considering the limited space. 

Considered adding a subwoofer but the wife won that coin toss so instead the bedroom got an upholstered chair...it doesn’t add much to the sound quality but does make for a nice spot to enjoy the music.

I have a 15' X 13' library or whatever it's called as a part of my bedroom.  Like lak, it gets whatever's not currently in the main system:
Jadis Orchestra Reference integrated
Jadis Defy DA30 integrated
Quicksilver 8417 monoblock power amplifiers
Dynaco ST70 X 2 stereoblock power amplifiers
VTV Ultrasonic preamplifier
AES AE3 DJH preamplifier
Dynaco CD player
Consonance SACD player
Sony SCD333ES SACD player
Technics SL7 turntable
Fried Valhalla (C satellites with O subwoofers) system
Fried Studio V
Fried A/6
Fried Beta
Coincident Digital Master satellites w/Troubass subwoofers