As of this posting: (Edit: I've seen the many responses since I started this post that answer the question posed)
there is no HD being broadcast on 101.9 FM (although on the station ID heard at around 12:44pm the HD1 is mentioned).
Likely the processing being used now is the same as it was for the FM News 101.9 format: mono (maybe occasionally weak stereo) for the main programming (in this current case, the music), then weak stereo (that could be heard on the HD signal only in the past) for the ads, bumpers, sweepers, etc.
There is no HD2 on 101.9 FM now, nor has there been for several weeks now. That used to be the Smooth AC format formerly known as "CD101.9", changed to "Smooth Jazz 101.9 HD2" or "Smooth FM 101.9 HD2" or "New York's Smooth 101.9 HD2" or similar wording.
+++For the New York Merlin station:
Besides the player currently on the WEMP-FM website
www.newrock1019.com - player link:
http://www.newrock1019.com/listen/
there are these "Listen Live" links:
pop-up flash player link:
http://den-a.plr.liquidcompass.net/player/flash/audio_player.php?id=WEMPFM&uid=579 64 K, 44.1 kHz stereo
direct URL link:
http://204.209.255.119/WEMPFMAAC 64 kbps, 44.1 kHz, stereo
direct URL link:
http://204.209.255.119/WEMPFMAACS 32 kbps, 44.1 kHz, stereo
+++For the Chicago stations that are Merlin Media properties:
---WIQI-FM-101.1 -
http://www.i101fm.com - i101 player link:
http://www.i101fm.com/listen/
there are these "Listen Live" links:
pop-up flash player link:
http://den-a.plr.liquidcompass.net/player/flash/audio_player.php?id=WWWNFM&uid=578 64K, 44.1 kHz stereo
direct URL link:
http://204.209.255.119/WWWNFMAAC 64 kbps, 44.1 kHz, stereo
direct URL link:
http://204.209.255.119/WWWNFMAACS 32 kbps, 44.1 kHz, stereo
---WLUP-FM-97.9 "The Loop":
pop-up flash player link:
http://den-a.plr.liquidcompass.net/player/flash/audio_player.php?id=WLUPFM&uid=576 64K, 44.1 kHz stereo
direct URL link:
http://204.209.255.119/WLUPFMAAC 64 kbps, 44.1 kHz, stereo
direct URL link:
http://204.209.255.119/WLUPFMAACS 32 kbps, 44.1 kHz, stereo
---WKQX-LP-87.7 "Q87.7" -
http://www.undergroundq.com/ Q87.7 player link:
http://www.dqtech.net/Q877/
direct URL link:
http://64.37.241.111:8000/q877
Check the playlist on the Q87.7 site above; likely it's similar to what will be used on WEMP NYC for the time being.