I recently bought the Back to the Future trilogy 25th anniversary BluRay box set but there's a BIG issue. The audio is in DTS HD Audio. Now, up till now, all my bluRay discs have been Dolby Digital True HD Audio. These discs give fantastic 5.1 audio through my Sony amp which is DTS and Dolby Digital compatible. However, the DTS HD encoded BluRay discs only give standard stereo audio. From what I understand, the audio should work in 5.1 on any DTS compatible amp yet all I get is stereo. The crazy thing is that all the BluRay menus are in 5.1 as are the universal logos but the actual movie isn't. Are my BluRay discs encoded wrong? Do I have to change some settings? As I said, my amp is DTS and Dolby Digital compatible and does play DolbyDigital True HD Audio just fine in 5.1. The audio runs from the BluRay player in to the TV via High Speed HDMI then from the TV to the amp via an optical cable. Yakumo
I think you have to have an amp with support for DTS HD Master Audio in order to get the full signal. Same goes for Dolby TrueHD. I think most Blu-ray players will convert TrueHD into either stereo or 5.1 (TrueHD is actually 7.1, I think). Probably what it's doing is converting it to standard Dolby Digital (AC-3). There might be an option in the Blu-ray settings to convert it to standard DTS instead. Neither DTS HD nor TrueHD can be transmitted over optical/toslink. They are both lossless, 5.1 or 7.1 (potentially more for TrueHD) audiostreams, and toslink is only capable of handling lossless audio (PCM) in stereo or lossy audio (AC-3 or DTS) in 5.1. The only way to get the full, unconverted signal is to connect the player to an amp via HDMI (if your amp has an HDMI port). Also, you have a Sony amp? WHAAA?!
Ah, so my BluRay player (which does have the True HD Audio and DTS HD logos on it) is converting the True HD audio to standard 5.1? I'm cool with that. Not an issue at all. Hmm, I wonder why it isn't doing the same for the DTS HD audio? From memory I have the Pioneer BluRay player downsampling the audio to 48khz and set as a Bitstream feed. Yeah, it is strange that I have a Sony amp but I'm on a tight budget and for the price this used set up packs a whopping punch in the audio department. Plus there are no lasers involved so far less shit to go wrong. I'll NEVER buy a Sony product that uses lasers. Yakumo
I think the reason it won't convert it to 5.1 is because it normally outputs Dolby Digital, and it can't convert DTS HD to Dolby Digital because of licensing issues or something. I would check in the audio settings of the Blu-ray player to see if there's an option to output DTS instead of Dolby Digital. You might also check in the "Set Up" (or something like that) section of the Blu-ray to see if there's a standard DTS track or a DD track. Most Blu-rays have a few different options for the audio.
Will do mate. I know the bluray discs don't have any English DD track though. Bloody stupid with the amount of space on the discs. I'll check the player's settings. Thanks for the help.
You may be better off setting the output of your Blu-Ray player to LPCM anyway, if both the player and receiver can do that, as it means the player isn't converting the lovely lossless audio into a lossy lower quality audio format.
Right, but the point was he wants 5.1 surround sound, and you can't transmit 5.1 PCM audio over toslink.
Hm, maybe the player just doesn't downconvert/downsample DTSHD to standard DTS. I've got an old Kenwood 5.1 receiver from around 01' and my LG blu-ray player seems to downconvert both to their respective formats over Toslink. Perhaps you can look up your specific model and read it's specifications or whatever(unless you have a manual?).
Yeah, I have a manual but it's Japanese. The player does have an English GUI though and full region free for DVD. Pioneer are great for region free with quality unlike the cheep Chinese shit. Anyway, I took a look at the menus last night and it seems there are no options for converting any format but it does automatically convert TrueHD audio to standard 5.1 over the toslink but not DTS-HD. I'll have a look online to see if there is a firmware update or something for it. It seems odd that it will do one format and not another when both are supported.
That's what bitstream refers to - the type of audio output, usually meaning something other than PCM. If you select that option it may let you choose what kind of bitstream to output. On my PS3 I can select PCM, DTS 5.1, DD 5.1, and a long list of others.
OK, I think I found out why DTS HD isn't being converted but True HD Audio is. I checked out the Hong Kong players manual which is in English and it states that the player will automatically convert HD audio (both formats) for any none HD 5.1 amp via the toslink. I use the bitsteam option but here's where the problem is I think. All audio to the amp goes through the TV first. This means I only need 1 toslink cable from the TV to amp for 5.1 audio from the DVD player, 360 and Blu-ray player. Anyway, the TV supports Dolby Digital and HD audio and DTS but doesn't mention DTS-HD. So it would seem that the TV can't pass on the 5.1 signal to the amp, turning it in to 2 channel stereo. Blu-Ray player out puts DTS-HD to the TV via HDMI. TV wonders "What the fuck is this?" and converts it in to standard stereo. That stereo track then comes out of the TV via the toslink in to the amp. I'm pretty sure this is the issue that is causing the sound problem. What I'll do when I get home is take the audio direct from the Blu-ray player in to the amp via Toslink and see if that gives 5.1 If it does then I know it's the TV causing the problem. Crazy though when normal DTS from DVDs works fine. Oh well..
Oh yeah. Sorry, brainfart happening right here - LPCM decoding of multi-channel audio is only available over HDMI, not Optical(TOSLINK). Well, that screws up my plan for building an awesome multichannel LPCM decoder .
Problem solved!! it was my TV which was causing the problem. It's not DTS certified so it had no idea what to do with the DTS audio signal and just turned it in to standard stereo. My amp has 2 toslink ports on the back so now one goes direct to the TV while the other goes direct to the blu-ray player. thanks for all the help guys. Yakumo
Ah so that explains it. I learned from my HD cable set top box a while ago that passing Surround sound through HDMI to my tv and from TV to Receiver was too much of a pain. I also learned that from using a 360 too, which won't pass through DD in games over HDMI to Toslink when plugged into the TV Instead it only outputs stereo once it gets to the receiver from the Toslink via the TV.
For me I have no problems with the 360 in 5.1 going through the TV via HDMI then to the amp via toslink because the TV is fully DolbyDigital and True HD Audio certified. I always though that meant any type of surround sound audio but now I know better.
That's odd , i'll have to try again sometime. Because I know my TV is DD certified. And I CAN pass through DD 5.1 from my Cablebox over HDMI to my receiver. To be honest though I haven't had this issue lately because I simply haven't played a 360 game this way since Halo Reach. Which was the game I remember having the issue with.
Sometimes my 360 will boot in to Stereo for some reason but if it does that I just reset the 360 and it always goes back in to 5.1 I think that may have something to do with the TV as well to be honest. It can automatically change to the correct channel of a HDMI contend device. but or some reason with the 360 it takes 3 seconds to change to the correct HDMI channel. I've NEVER seen the full boot logo of my 360. The Blu-Ray player works in the same way but can even be controlled by the TV remote which is Toshiba however the Blu-ray player is Pioneer.
Technically S/PDIF (Toslink or Coax) can transmit uncompressed 5.1 fairly easily, the packet format was just never standardized. S/PDIF can even transmit uncompressed 7.1/96 kHz/24 reliably with decent equipment. If greed didn't enter the equation then surely any TV today could pass any audio from HDMI out S/PDIF to be decoded by the receiver. Of course this would mean cheaper TVs, cheaper receivers, fewer HDMI cable sales and fewer devices with Dolby/DTS licensing, not very capitalistic.
Personally stereo is enough for me. I used to have a surround setup, but it gets rather complicated and it's not very good for stereo sources, which is a lot of what I listen to. I have a small DAC connected to my TV, and all my devices are set to output PCM, so when I play a watch a Blu-ray I get uncompressed sound. I listen to a lot of CD's, so it's good for that. If I were rich I'd probably have separate setups for movie-watching and music. I've been playing around with the HDMI-CEC stuff lately with some limited results. I can't control my PS3 with my TV remote, but I have found that when it's enabled, turning my PS3 on will turn on my TV and set it to the correct input (sometimes), and turning off my TV will also turn off my PS3.
