Here it is. From a review of the ST60 by Home Theater magazine May 24, 2013
"If you expect to connect a soundbar and have the TV perform switching among HDMI sources such as a cable box and Blu-ray player, be advised that the ST’s optical digital audio output you’ll use to feed the soundbar downconverts all multichannel Dolby Digital and DTS bitstreams to PCM stereo, which will bypass any DD or DTS decoder built into the soundbar and result in less-than-best sound quality. This practice is unfortunately common to most HDTVs today."
Just found several reviews of the VT60. Fantastic picture and speakers sound better than most.
So far not one tested the digital audio out. HT reviewed the VT50 but didn't test the audio out.
For those that use a soundbar that Samsung may be a better deal. And the VT60 might not
be downmixing, but it very likely is and most brands/models still are degrading digital audio as
it passes through the tv.
Very interesting great information! Thank you for posting that. I wish I had the set up to just add a true 5.1 speaker system and a receiver but I really do not. That is the reasoning with going with a sound bar.
I am now back at looking at the original sound bar I was going to get the Polk audio 9000 IHT.
It says it can decode and reproduce Dolby Digital 5.1 and DTS 5.1. It also says many sound bars can decode 5.1 but only reproduce it as two channel stereo. This Polk audio plays back all discrete channels as intended.
Having read the post above about the optical output on the Panasonic's, now I'm wondering if this Polk audio would be a waste of money and I should just stick with that JBL SB 400.