Explain the DTS stream & LPCM remux thing to me, please?

[Ruoska]

I googled around and figured you should use bitstream for SPDIF and LPCM for HDMI. My PS3 is connected to the receiver (Yamaha RX-V565) via HDMI so I'll go with LPCM. I'm getting nice 5.1 when streaming movies, everything sounds fine but they're always reported as 2ch stereo on the PS3.

What do the options "Keep DTS audio in stream" and "DTS/FLAC -> LPCM remux" exactly do? Do I need to keep DTS audio in the stream?

Are there pros and cons to this or is this a simple "this is better for you" sorta thing depending entirely on your method of audio signal transfer (optical or HDMI)?

Thanks for your time and obviously HUGE thanks to the developers of this software and the subjunk builds, if they happen to read this

[Val Killmore]

If you are using HDMI cables, disable "Keep DTS audio in stream", and enable "DTS/FLAC->LPCM remux"

This will make PMS pass the DTS to the PS3 as multi-channel LPCM ( Linear Pulse Code Modulation ) uncompressed audio. These two options are in PMS to allow movies with DTS to be streamed to the PS3 with minimal quality loss (less than encoding to AC3)as it only accepts DTS on hard media (DVD discs or AVCHD discs).

"Keep DTS in stream" option is for optical cable set ups. This basically hands off the decoding of DTS audio to your amp.
Optical cables, though they sound nice, are limited in they can only pass 2 channel LPCM uncompressed audio, which limits it for the new HD audio formats (True-HD, DTS-HD Master Audio), and I believe only up to 5.1 audio max with regular Dolby and DTS......no 7.1 audio. Also, optical are just delicate if you're not careful.

HDMI is the way to go in my opinion. Especially with the new low cost home theatre setups that come with multiple HDMI inputs to allow source switching. I just picked up a HT-SS370 Sony BluRay amp system. I only use my Xbox360 with optical.

[ExSport]

If you are using HDMI cables, disable "Keep DTS audio in stream", and enable "DTS/FLAC->LPCM remux"

Totally wrong suggestion
If you have Receiver with DTS support, enable "Keep DTS...". In this case PMS will send not touched original DTS stream(masked as LPCM 2.0) directly to your receiver.
It doesn't matter if HDMI or Optical cable used.
Yes, PS3 doesn't support DTS when played outside physical media(DVD/BD). Because of that DTS is masked as LPCM 2.0 so PS3 ignores any audio processing and send it to receiver as is.
So everybody who has external receiver with DTS support, use "Keep DTS..." instead of LPCM remux. Also this remux can't work with optical cable because of bandwidth limitation. Optical/Toslink doesn't support more than stereo uncompressed LPCM stream.

[Val Killmore]

Totally wrong suggestion
If you have Receiver with DTS support, enable "Keep DTS...". In this case PMS will send not touched original DTS stream(masked as LPCM 2.0) directly to your receiver.
It doesn't matter if HDMI or Optical cable used.
Yes, PS3 doesn't support DTS when played outside physical media(DVD/BD). Because of that DTS is masked as LPCM 2.0 so PS3 ignores any audio processing and send it to receiver as is.
So everybody who has external receiver with DTS support, use "Keep DTS..." instead of LPCM remux. Also this remux can't work with optical cable because of bandwidth limitation. Optical/Toslink doesn't support more than stereo uncompressed LPCM stream.

So then I assume the receiver then takes the 2.0 lpcm stream and can decode it then send 5.1 audio to the speakers?

I understand and acknowledge everthing else you pointed out, but have long misunderstood ( obviously ) the 2.0 lpcm thing.

I will try this.

[Val Killmore]

Hmmm. Nice one Export.

I get the DTS lite on the receiver display window now, and it seems like the audio is correct at first glance, or listen I should say.

The whole thing that has had me confused, as I only just got this receiver and recently started learning about the different audio options, is the labelling in PMS, and my misunderstanding of how "Keep DTS in stream....." works with the 2 ch. lpcm. I guess I interpreted "compatible with optical" as "keep DTS in stream needs/works with optical".
And interpreted DTS/FLAC remux--->LPCM "You need an HDMI receiver..." as "choose this option for use with HDMI out". Your little explanation has straightened out hours of confusion and surfing for me.

I don't really hear a difference or see an advantage though to "keep DTS in stream", in fact I actually think it sounds better with the DTS remux to 5.1 lpcm option. Maybe I am just tripping ? I mean, 4.6 Mbps w/HDMI and DTS/FLAC --> remux option vs. 1.5 Mbps w/HDMI and "Keep DTS in stream option"

Both sound great though, either way.

I guess I will have to play with it some more. Thanks Export.

PS.....it is cool to see the DTS light come on though. I mean I did pay for it....lol

[meskibob]

Considering that your source is 1.5 Mbps DTS, 4.6 Mbps LPCM doesn't really mean much. As to the sound difference, there's no real difference other than being able to use the decoding capabilities of your receiver. However, that could mean different processing is applied to each type (LPCM vs DTS bitstream) depending on how you've configured your receiver or just the receiver itself.
And to note, you can leave both options enabled, so DTS is left as DTS and FLAC is still converted to LPCM.

[Val Killmore]

Considering that your source is 1.5 Mbps DTS, 4.6 Mbps LPCM doesn't really mean much. As to the sound difference, there's no real difference other than being able to use the decoding capabilities of your receiver. However, that could mean different processing is applied to each type (LPCM vs DTS bitstream) depending on how you've configured your receiver or just the receiver itself.
And to note, you can leave both options enabled, so DTS is left as DTS and FLAC is still converted to LPCM.

Thanks Meskibob....and Export.

Now, I have a weird one. I can get the DTS to show as DTS on my receiver. But Dolby Digital is still coming thru as LPCM for some reason.

Both DTS options are ticked like you suggested Meskibob. And AC3 remux is enabled. But Dolby is not lighting up at all no matter the source. Only the LPCM light.

I think I am missing something. Almost there, but not quite. Thanks for the help and straightening out my confusion so far.

[meskibob]

It is working as designed. If your PS3 is set to output LPCM, it will decode AC3 and send it to your receiver as LPCM. The 2.0ch LPCM trick only works for DTS and is there because the PS3, as ExSport detailed, doesn't support DTS for non-disc media.

[Val Killmore]

Cool. I think I get it now. I have literally spent hours reading about it, but end up lost at the 2.0 lpcm / DTS decoding part. Very nice, thanks.

PS...think I'll leave her on lpcm after all this, but glad you helped me get a better grasp on it. I would plus rep you if this site used that system. Works nice with BluRay playback and the HD codecs too.

[wyowolf]

I just got a new Denon AVR 991 and when i tried to play my 1080P MKV with DTS i get static? for sound, but the picture plays fine? I have both LPCM and the keep DTS instream options checked? what am I doing wrong? When i play regular AVI files, it plays and sounds fine, its only the 1080P files which i cant get DTS to work?