Audio hardware and software configuration

This wiki article should cover all your general questions about how to connect up your OSMC device to get the best audio possible. There’s also a section with explanations of some of Kodi’s audio settings as well as information about the audio capabilities of our OSMC devices.


Supported devices

OSMC supports a range of devices: All Raspberry Pis and our own Vero series (Vero 1, Vero 2, Vero 4K, Vero 4K + and Vero V).

  • Veros have an HDMI port for video and audio, a 3.5mm port for analogue audio and composite video (A/V) (not Vero 1) and an S/PDIF port (TOSLINK or coaxial).
  • Raspberry Pis have an HDMI port and a 3.5mm A/V port. Third-party HATs are available to provide better quality analogue and S/PDIF audio.

Users can also connect USB soundcards to any OSMC supported device. Most high-quality USB soundcards output only analogue stereo.

This post is about cable audio connections. Audio output to Bluetooth is also supported.

In this post, display means your TV, monitor or projector and amplifier means your AVR, soundbar, receiver, analogue amp or anything else you use for audio output. Where we say ‘TV’ this may also apply to monitors with speakers. How you connect up your display and your amplifier depends on the capabilities of your equipment. The following recommendations are general. You will have to read the manuals for your display and amplifier carefully to get the best arrangement, especially if you want CEC to work in a particular way.

Acronyms
Use your favourite search engine if you don’t understand the following terms

Needed: HDMI, AVR, ARC, CEC, DD, AC-3, DTS, (L)PCM.
May need: S/PDIF, TOSLINK, USB, HAT (for Raspberry Pi), CVBS, TRS, TRRS, OMTP, CTIA, DVI, VGA.


Different setups explained

1. You have a display with an HDMI input and you have an amplifier with HDMI inputs and outputs.

Connect your OSMC device HDMI output to one amplifier HDMI input and connect the display to one amplifier HDMI output. Use ARC/eARC ports if available but this is not essential. You will be able to play all audio and video formats that your amplifier supports. If your display accepts more video formats than your amplifier can pass through (e.g. 4k @ 50/60Hz) you will need an HDMI splitter to enjoy those and at the same time using the full audio capabilities of your amplifier.

Go here and follow the recommendations for audio settings in Kodi for an AVR using HDMI.


2. You have an amplifier with no HDMI inputs to plug your OSMC device into

Connect your OSMC device’s HDMI output to your display. You have two basic options for audio as follows.

2.1. Connect your amplifier to your OSMC device not using HDMI

You will not be able to use your amplifier to play audio from the display with this arrangement but may be able to play more digital formats than using using option 2.2.

2.1.1. If your amplifier has TOSLINK (optical) inputs:

  • connect your Vero’s (1, 4K, 4K + or V) TOSLINK output (or RPi HAT TOSLINK) to your amplifier.
    or
  • connect your Vero 2’s S/PDIF output through a coaxial-TOSLINK converter.

You will be able to play stereo LPCM and will most likely be able to play DTS and DD 5.1 surround (but not DTS-MA or TrueHD) depending on your amplifier’s capabilities.

2.1.2. If your amplifier has a digital coaxial input:

  • connect your Vero’s (1, 4K, 4K + or V) TOSLINK output through an optical-coaxial converter to your amplifier.
    or
  • connect your Vero 2’s S/PDIF output to the amplifier.
    or
  • connect your RPi HAT digital port to the amplifier, using a converter if necessary.

This will perform the same as 2.1.1. above, except some coaxial inputs offer higher samplerates than some TOSLINK inputs (TOSLINK is often limited to 24 bit 96 kHz).

2.1.3. If your amplifier only has analogue inputs, connect your amplifier to your OSMC device’s analogue output (this option is not available for Vero 1).

Note: The A/V port on Vero 2, 4K, 4K + and V is the 3.5mm jack nearer to the ethernet port. For audio only, you can use a standard TRS plug. When using a TRRS plug on Vero 4K, 4K + and Vero V it must be wired as ‘OMTP’, i.e. left-right-video-ground. The 3.5mm A/V port on Vero 2 and Raspberry Pi is ‘CTIA’, i.e. left-right-ground-video. See here for a good explanation.

Go here and follow the recommendations for audio settings in Kodi for S/PDIF or analogue output as appropriate.

2.2. Connect your amplifier to an output on your display

With this option, you will be able to play audio from the display (e.g. terrestrial TV) to your amplifier but you may only be able to send stereo to your amplifier.

2.2.1. If your amplifier has digital inputs and your display has a digital output, connect your display’s digital output to your amplifier, if necessary using a TOSLINK-coaxial or coaxial-TOSLINK converter. You will be able to play stereo and may be able to play DTS and DD 5.1 surround.

2.2.2. If your display does not have a digital output, connect the display’s analogue audio out or headphone jack to your amplifier. You will only be able to play stereo. You will likely get better quality audio directly from your Vero or your Raspberry Pi’s analogue HAT than from your display, but you will definitely get better quality audio from the display than from Raspberry Pi’s on-board audio jack.

2.2.3 Some soundbars have only a single HDMI socket intended for use with ARC or eARC. If your display supports ARC/eARC connect that input to your soundbar. See (5) below.

Go here and follow the recommendations for audio settings in Kodi for an AVR using HDMI.


3. You have an amplifier and your display has no HDMI input.

3.1. You can connect your OSMC device (except Vero 1) to your display’s composite video input (if available) using the device’s A/V port. You cannot then use the HDMI port for audio only. You can only use the analogue or S/PDIF ports as described in 2.1. above.

3.2. You can choose from a variety of HDMI video and audio converters and splitters that suit your display and sound equipment, for example HDMI to DVI/VGA/composite/component with various audio interfaces - TOSLINK, digital coaxial or analogue.


4. You have no amplifier.

Connect your OSMC device to your display by HDMI or using one of the methods in 3. above.

Go here and follow the recommendations for audio settings in Kodi for an AVR using HDMI or go here and follow the recommendations for audio settings in Kodi for an amplifier using analogue.


5. A special case: using (e)ARC.

(e)ARC: If you want to play audio through your display to your amplifier (e.g. when a TV is tuned to a terrestrial station) use the display’s input that supports (e)ARC. If you don’t have (e)ARC capability on either your display or AVR, you will have to use another display audio output (analogue or S/PDIF).
(e)ARC is not used when playing media from your OSMC device through your amplifier.

Some users may wish to connect their OSMC device directly to their display and still use (e)ARC back to their amplifier, for example, if the TV supports HDR while the amplifier does not.

  • ARC does not support HD audio - only the formats supported by S/PDIF. In this case, you will have to choose Kodi’s audio settings as if you were using S/PDIF output. It is also possible your display will not accept DTS and/or Dolby Digital (AC3). In that case, there is no way to get multi-channel audio to your amplifier through ARC. You must set Kodi’s output channels to 2.0 so that multi-channel audio is mixed down to stereo. If you can’t hear speech from the front-centre channel, that setting is the first one to check.
  • eARC does support HD audio - it can handle the same formats HDMI “normally” can. In this case, you will have to choose Kodi’s audio settings as if you were using HDMI output. It is possible your eARC capable display does not support passthrough of all audio formats to a connected amplifier. Please refer to your display’s manual for more information (or test it by trial and error). If your display doesn’t pass through all the formats you want to get to your amplifier, connect your OSMC device directly to one of your amplifier’s HDMI inputs and your display to one of your amplifier’s HDMI outputs, or use an HDMI splitter.

Recommended audio settings for different scenarios


When using the HDMI output of your OSMC device for audio

Go to Settings/System/Audio… Select the following settings (keep in mind to set the settings level to ‘Expert’ in the bottom left corner of the settings window to see all settings necessary) :

  • Audio device:
    • Vero 2, 4K/4K +, V: PCM or HDMI
    • Vero 1: HDMI
    • Raspberry Pi: HDMI
  • Number of channels: 7.1 (so your AVR/soundbar/TV can do the processing of LPCM according to your speaker setup)
    • Some HDMI devices can only process 2-channel LPCM! Please check your AVR/soundbar/TV’s manual for a list of supported HDMI audio formats… If your AVR/soundbar/TV only supports 2-channel LPCM, please set Number of channels to 2.0 and enable AC3 transcoding, if you don’t want all HD audio down-mixed to 2.0 LPCM (also see the explanation of AC3 transcoding )
  • Output configuration: Best match
  • Passthrough: enabled (on Raspberry Pi select Passthrough device: HDMI )
  • DTS/AC3 passthrough: enabled
  • DTS-HD passthrough: enabled* (if your AVR/soundbar/TV supports it)
  • TrueHD passthrough: enabled* (if your AVR/soundbar/TV supports it)
  • E-AC3 passthrough: enabled (if your AVR/soundbar/TV supports it)

*Vero 2 and all Raspberry Pis except the Raspberry Pi 4 do not support DTS-HD or Dolby TrueHD passthrough. If you’d like to get the best audio experience by decoding HD audio DTS-HD or Dolby TrueHD tracks to surround LPCM, disable this setting on your Vero 2 or RPi (except 4). This also applies, if you connect up your Vero 1, Vero 4K/4K +, Vero V or your Raspberry Pi 4 to an AVR not capable of processing HD audio via HDMI. If you leave it enabled, instead of decoding DTS-HD to surround LPCM, only the core DTS track will be passed on - losing audio quality this way.

Keep in mind to disable “Sync playback to display” under Settings/Player/Videos for passthrough to work!


When using the S/PDIF output of your OSMC device for audio

Go to Settings/System/Audio… Select the following settings (keep in mind to set the settings level to ‘Expert’ in the bottom left corner of the settings window to see all settings necessary) :

  • Audio device:
    • Vero 2, 4K/4K +, V: PCM or HDMI
    • Vero 1: S/PDIF
    • Raspberry Pi: your S/PDIF soundcard
  • Number of channels: 2.0 (S/PDIF only supports 2-channel LPCM)
  • Output configuration: Best match
  • Passthrough: enabled (on Raspberry Pi select Passthrough device: your S/PDIF soundcard)
  • DTS/AC3 passthrough: enabled
  • DTS-HD passthrough: disabled (only present on Vero 1, Vero 4K/4K +, Vero V and Raspberry Pi 4)
  • TrueHD passthrough: disabled (only present on Vero 1, Vero 4K/4K +, Vero V and Raspberry Pi 4)
  • E-AC3 passthrough: disabled
  • AC3 transcoding: enabled (enable this if you don’t want multi-channel LPCM and HD audio down-mixed to 2.0 LPCM, also see the explanation of AC3 transcoding a bit further down)

Keep in mind to disable “Sync playback to display” under Settings/Player/Videos for passthrough to work!


When using the analogue output of your OSMC device for audio

Go to Settings/System/Audio… Select the following settings (keep in mind to set the settings level to ‘Expert’ in the bottom left corner of the settings window to see all settings necessary) :

  • Audio device:
    • Vero 2, 4K/4K +, V: PCM or HDMI
    • Vero 1: HDMI
    • Raspberry Pi: Analogue
  • Number of channels: 2.0
  • Output configuration: Best match
  • Passthrough: disabled

Keep in mind that the analogue port is not amplified to power low sensitivity headphones at a satisfactory volume level!


Some of the audio settings explained in more detail


Output configuration

The Kodi wiki states the following concerning this setting (AudioEngine , under 5.3 ActiveAE):

ActiveAE has three build-in profiles: Best Match, Optimized and Fixed.

  • Fixed takes care that all audio you will play is play in the very same data format. Your receiver does not need to switch modes.
  • Best Match is what previously existed as the “audiophile” mode. Whenever a new video or music playback starts, the audio engine will select the best sink for that stream. By design Best Match and gapless playback are not compatible. If you rely on gapless playback, consider using Optimized instead.
  • Optimized is something special, as it tries to reduce the reopening of sinks a lot. One example is live-TV where it switches between 5.1 to 2.0 during commercials. In order to not open the device anew and loosing some (milliseconds of) audio, the 2.0 commercials are played with the already open 5.1 sink by muting the non existent channels.

We recommend using Best match all the time for these reasons:

  • Fixed resamples everything (that doesn’t match the selected output samplerate), but most audio hardware can process all audio samplerates anyway.
  • Optimized may produce very weird results when queuing different audio files for playback. Especially when files with different channel layouts are mixed in a queued playback (e.g. 2.0 and 5.1 files), sound may be played from wrong/unexpected speakers.
  • Also, both fixed and optimized are not recommended, if you’re interested in bit-perfect playback (which the Vero 4K/4K +/V supports, see here: Can Vero do bit-perfect playback? ). Those two settings will resample your audio files often or most of the time (optimized resamples, if the samplerate of a queued files is not the same as the samplerate of the file before that in your queue).

If you’re interested in bit-perfect playback , set the output configuration to Best match and set the Kodi volume to 100% (using a Kodi remote app e.g.)!

Keep in mind to set the settings level to ‘Expert’ in the bottom left corner of the settings window to see all settings.


AC3 transcoding

This setting is only available if you set the Number of channels to 2.0. In this case, surround LPCM channels will normally be downmixed and HD passthrough formats will be decoded and down-mixed to LPCM 2.0. If you want to retain surround audio also with those formats in this scenario, AC3 transcoding will do the trick: It transcodes all LPCM and HD audio stream’s surround audio into a lossy 5.1 Dolby Digital (AC3) stream on-the-fly to give you the best surround sound possible with your setup.
Just keep in mind: Same as decoding of lossless tracks to LPCM, transcoding won’t preserve any 3D audio information of DTS:X, Dolby Atmos or AURO-3D - the 3D metadata can only be streamed to a capable receiver when the audio stream is transported untouched!

Keep in mind to set the settings level to ‘Expert’ in the bottom left corner of the settings window to see all settings.


Keep audio device alive

This setting is not needed in the normal use case of your OSMC device. It’s meant for systems where more than one audio application wants to use the audio sink. The keep alive setting will force Kodi to always retain control of the audio sink thus making it impossible for other audio applications to take over. As the normal use case of your OSMC device only has one application that will make use of the audio sink (Kodi), this setting can be ignored and it basically doesn’t matter what you set it to.


Send low volume noise

This setting helps with two issues, if you’re sensitive about them:

  1. The audio sink of the Vero takes a very short time to open which leads to a short period of silence before the actual audio is audible (this mostly affects PCM playback, not so much passthrough).

  2. Some audio receiving equipment falls into a standby mode when no audio information is received through its input. This setting may help preventing an audio receiving device from going into standby. It has also been reported that some audio receiving devices make strange “plop” noises when the state of the input changes. So, this setting may help to prevent too many changes from happening (by keeping the Vero’s audio sink open all the time).


Mute HDMI audio (Vero 4K/4K +/V only)

This setting is audio related, but it is to be found in a different settings window: Settings/System/Video. Enable this setting, if you’re e.g. connecting your Vero 4K/4K +/V to your TV via HDMI and to your AVR/soundbar via S/PDIF/analogue and you don’t want the TV to receive any audio via HDMI. The setting will mute audio on HDMI only - S/PDIF and analogue will still output audio.


FAQs


What is HD audio?

HD audio files are considered audio formats that can be passed through via HDMI by our Vero 1 and Vero 4K/4K +/V (not the Vero 2 or any Raspberry Pi except the Raspberry Pi 4). These include: Dolby TrueHD, Dolby Atmos, DTS-HD MA, DTS:X and AURO-3D.
Dolby Digital Plus (or DD+/E-AC3) and DTS-HD HRA are special cases as they sit somewhere between HD and non-HD audio.


Why can’t I passthrough HD audio via S/PDIF?

S/PDIF’s maximum supported bandwidth equals the audio bandwidth needed for 2-channel 24 bit 192 kHz PCM audio. The bandwidth needed for HD audio to be passed through is a lot higher - which is only supported by the HDMI interface. Be aware: some older and even today’s equipment only supports a maximum of 2-channel 24 bit 96 kHz PCM audio via S/PDIF!


Why are Dolby Digital Plus (E-AC3) and DTS-HD HRA special cases?

Dolby Digital Plus and DTS-HD HRA are using a bandwidth equal to 2-channel 24 bit 192 kHz PCM audio which is supported by some S/PDIF equipment. If your AVR/soundbar/TV supports Dolby Digital Plus, DTS-HD HRA and offers support for 2-channel 24 bit 192 kHz via S/PDIF, passthrough of Dolby Digital Plus and DTS-HD HRA may also work via S/PDIF. This is the reason why Dolby Digital Plus and DTS-HD HRA are sitting in the middle of HD and non-HD audio, so to say.


Which versions of Dolby Atmos and DTS:X are there? And how is AURO-3D different?

Dolby Atmos and DTS:X exist in two different versions each. Both 3D audio formats are additions to existing Dolby and DTS audio formats in the form of added audio metadata for 3D audio objects. Older equipment that doesn’t support Atmos and DTS:X will just ignore the metadata. Dolby Atmos can have either a Dolby TrueHD core (which would be lossless Atmos) or a Dolby Digital Plus core (which would be lossy Atmos). The same applies for DTS:X: The core can either be DTS-HD MA (lossless) or DTS-HD HRA (lossy). Lossy Atmos is quite common for streaming applications nowadays (like Netflix or Amazon Prime Video) whereas the lossy version of DTS:X is still very rare and mostly used on non-English BD or UHD BD releases for space reasons (secondary DTS:X tracks).
AURO-3D is also an addition to a core audio stream, but it doesn’t utilize 3D audio objects. It adds another layer of fixed audio channels on top of the existing 5.1 or 7.1 channels. The core audio format used for AURO-3D is one of these two lossless formats: LPCM or DTS-HD MA. There is no lossy version of AURO-3D and the most used channel layout for AURO-3D is 9.1 at the moment (5.1 ear level speakers, 4 upper level speakers). It supports 11.1 and 13.1 speaker layouts as well.


Which passthrough formats are supported by OSMC devices (not all are supported by all devices) and which of them can be passed through via S/PDIF or HDMI?

Be aware: Those formats that are not supported for passthrough by some of the OSMC devices will either be decoded to a surround LPCM stream by the device (via HDMI) or it will be transcoded to Dolby Digital/AC3 (via S/PDIF).

By Digital Theater Systems, Inc./Xperi Corporation

  • DTS, with all channel layouts from 1.0 all the way to 5.1, at samplerates of 32, 44.1 or 48 kHz and a bit-depth of 16, 20 or 24 bit
    (supported via S/PDIF and HDMI)
  • DTS-ES (DTS Extended Surround), with either the Matrix or the Discrete extension, both offer 6.1 channels, with “Matrix” mixing the extra channel into the surround channels and “Discrete” adding an extra channel that is not mixed into the surround channels
    (supported via S/PDIF and HDMI)
  • DTS 96/24, which offers up to 5.1 channels with a samplerate of 96 kHz and a bit-depth of 24 bit
    (supported via S/PDIF and HDMI)
  • DTS-HD HRA (DTS High Defintion High Resolution Audio) or DTS-HD Hi Res, DTS’ intermediate format between HD and non-HD audio, offering a higher bitrate encoding, still lossy, with up to 7.1 channels, a samplerate of up to 96 kHz and a bit-depth of up to 24 bit
    (supported via HDMI, theoretically also supported by S/PDIF, but only with HRA-capable hardware that supports 192 kHz via S/PDIF)
  • DTS-HD MA (DTS High Defintion Master Audio), with lossless encoding, up to 5.1 channels at a samplerate of up to 192 kHz and a bit-depth of up to 24 bit or up to 7.1 channels at a samplerate of up to 96 kHz and a bit-depth of up to 24 bit
    (only supported on Vero 1, Vero 4K/4K +, Vero V and Raspberry Pi 4 via HDMI)
  • DTS:X, the 3D audio format of DTS, based either on DTS-HD HRA or DTS-HD MA, providing up to 9 additional 3D sound objects with a samplerate of up to 96 kHz and a bit-depth of up to 24 bit (when based on DTS-HD MA) or with a samplerate of up to 48 kHz and a bit-depth of up to 24 bit (when based on DTS-HD HRA)
    → the audio objects are mixed into the audio stream and decoded according to the metadata sent along with the audio stream - a decoder that doesn’t support DTS:X just decodes the normal audio stream ignoring any 3D information
    (supported only on Vero 1, Vero 4K/4K +, Vero V and Raspberry Pi 4 via HDMI when DTS-HD MA-based, technically also supported via S/PDIF when DTS-HD HRA-based, but only with DTS:X-capable hardware that supports 192 kHz via S/PDIF)

DTS-HD HRA, DTS-HD MA as well as the basis of DTS:X tracks are required to carry a lossy DTS core for backward compatability reasons. Some examples: a DTS-HD MA 6.1 track would most likely carry a DTS-ES (6.1) core, a DTS-HD HRA track (with a bit-depth of 24 bit and a samplerate of 96 kHz) would most likely carry a DTS 96/24 core, a DTS-HD MA 5.1 track would carry a DTS 5.1 core and a DTS-HD MA 7.1 based DTS:X track would include a lossy DTS 5.1 core (the same applies to AURO-3D tracks based on DTS-HD MA).
→ If your equipment can’t decode lossless HD audio, Kodi will only send the core to your equipment (if you’ve disabled DTS-HD passthrough and enabled DTS passthrough accordingly, see above).

By Dolby Laboratories, Inc.

  • Dolby Digital or AC3, with all channel layouts from 1.0 all the way to 5.1, at samplerates of 32, 44.1 or 48 kHz and a bit-depth of 16, 20 or 24 bit
    (supported via S/PDIF and HDMI)
  • Dolby Digital EX (Dolby Digital Extended Surround), which adds another one or two rear surround speakers to the Dolby Digital 5.1 layout (resulting in 6.1 or 7.1 channels), the additional information is mixed into the surround channel information of the Dolby Digital stream
    (supported via S/PDIF and HDMI)
  • Dolby Digital Plus or E-AC3, Dolby’s intermediate format between HD and non-HD audio, offering a higher bitrate encoding, still lossy, with up to 7.1 channels (up to 13.1 channels in theory), a samplerate of 32, 44.1 or 48 kHz and a bit-depth of up to 24 bit
    (supported via HDMI, theoretically also supported by S/PDIF, but only with E-AC3-capable hardware that supports 192 kHz via S/PDIF)
  • Dolby TrueHD with lossless encoding, up to 5.1 channels at a maximum samplerate of 192 kHz and a bit-depth of up to 24 bit or up to 7.1 channels (up to 15.1 channels in theory) at a samplerate of up to 96 kHz and a bit-depth of up to 24 bit
    (only supported on Vero 1, Vero 4K/4K +, Vero V and Raspberry Pi 4 via HDMI)
  • Dolby Atmos, the 3D audio format of Dolby, based either on Dolby TrueHD or Dolby Digital Plus, providing an additional maximum of 20 3D sound objects with a samplerate of up to 96 kHz and a bit-depth of up to 24 bit (when based on Dolby TrueHD) or 9 3D sound objects with a samplerate of up to 48 kHz and a bit-depth of up to 24 bit (when based on Dolby Digital Plus)
    → the audio objects are mixed into the audio stream and decoded according to the metadata sent along with the audio stream - a decoder that doesn’t support Dolby Atmos just decodes the normal audio stream ignoring any 3D information
    (supported only on Vero 1, Vero 4K/4K +, Vero V and Raspberry Pi 4 via HDMI when Dolby TrueHD-based, technically also supported via S/PDIF when Dolby Digital Plus-based, but only with Atmos-capable hardware that supports 192 kHz via S/PDIF)

Dolby TrueHD and Dolby Digital Plus don’t carry a lossy Dolby Digital core track like DTS-HD formats do carry a lossy DTS track. On the Blu-ray and UHD Blu-ray disc an additional lossy Dolby Digital track is a requirement however (mostly as a non-visible companion (not core!) Dolby Digital track).
→ If your equipment can’t decode lossless HD audio, this companion track can be selected manually in Kodi when playing back such a BD/UHD BD TrueHD track or Kodi will only send the companion track to your equipment automatically (if you’ve disabled Dolby TrueHD passthrough and enabled Dolby passthrough accordingly, see above). If there’s no additional Dolby Digital track coming with the Dolby TrueHD or Dolby Digital Plus track, the lossless track would need transcoding to Dolby Digital or decoding to LPCM by the source device.

By Auro Technologies

  • AURO-3D is a special 3D audio format based on two lossless format audio streams - LPCM or DTS-HD MA with a bit-depth of 24 bit - with a samplerate of up to 96 kHz, an actual bit-depth of 20 bit per audio layer, offering 5.1 or 7.1 ear level channels, 2, 4 or 6 over-head channels and an optional VoG (Voice of God) channel on top and/or an additional center hight channel above the normal front center channel: between 9.1 and 13.1 channels in total
    → the extra channels are squeezed into the lower 4 bits of the 24 bit bit-depth and the actual bit-depth of 20 bit per audio layer is achieved by a mathematical trick interweaving the layers into one audio signal, the decoding is done according to the metadata sent with the audio data - a decoder that doesn’t support AURO-3D just decodes the normal audio stream ignoring the lower 4 bits of the 24 bit bit-depth
    (only supported on Vero 1, Vero 4K/4K +, Vero V and Raspberry Pi 4 via HDMI)

If AURO-3D is based on DTS-HD MA, it will carry a lossy DTS track.
→ If your equipment can’t decode lossless HD audio tracks, those AURO-3D tracks based on LPCM would need transcoding to Dolby Digital (the only way for Kodi to compress LPCM) or decoding to LPCM by the source device. If the AURO-3D track is based on DTS-HD MA, the lossy DTS core will be sent to your equipment (if you’ve disabled DTS-HD passthrough and enabled DTS passthrough accordingly, see above).


Which LPCM output formats are supported by OSMC devices via HDMI and S/PDIF?

  • Vero 4K/4K +/V/Raspberry Pi 4
    • HDMI: a samplerate of up to 192 kHz, a bit-depth of up to 24 bit and all channel layouts from 1.0 all the way to 7.1 (the surround center channel of 6.1 is mapped equally to both 7.1 back surround channels)
    • S/PDIF (built-in TOSLINK): a samplerate of up to 192 kHz, a bit-depth of up to 24 bit and 2.0 channels
  • Vero 2
    • HDMI: a samplerate of up to 192 kHz, a bit-depth of up to 24 bit and 2.0 channels
    • S/PDIF (built-in Coax): a samplerate of up to 192 kHz, a bit-depth of up to 24 bit and 2.0 channels
  • Vero 1
    • HDMI: a samplerate of up to 192 kHz, a bit-depth of up to 24 bit and 2.0 or 7.1 channels
    • S/PDIF (built-in TOSLINK): a samplerate of up to 192 kHz, a bit-depth up to 24 bit and 2.0 channels
  • Raspberry Pi
    • HDMI: a samplerate of up to 192 kHz, a bit-depth of up to 24 bit and 2.0 channels, but only a samplerate of up to 96 kHz with more than 2.0 channels (up to 7.1 channels)
    • S/PDIF: depending on your S/PDIF capable soundcard (HAT or USB)

Is passthrough of DSD via HDMI supported?

Neither of the OSMC devices support any sort of DSD passthrough via HDMI - be it DoP (DSD over PCM) or native DSD streaming. Any DSD container that can be played back by Kodi will be decoded to 24 bit 192 kHz PCM and sent to the AVR afterwards.
Keep in mind: The DSD to PCM conversion (not just decoding!) is happening on-the-fly and puts a lot of load on the CPU. Therefore some files may play ok and others won’t (DSD64 2.0 and DSD128 2.0 are mostly fine on Vero 4K/4K +/V, more demanding DSD versions like surround DSD or DSD256 and more can cause stutter and heat issues, all other devices than Vero 4K/4K +/V will probably not play DSD fine at all).

3 Likes

Hi Chillbo, I appreciate all the info.
It has come to my attention that ffmpeg has a default compressed dynamic range for AC3 that can be bypassed with advancedsettings.xml. Could you include this in your guide please?

1 Like

I wonder why this is an advancedsettings option and if it should be exposed as a setting?

There seems to be something wrong in the guide. Dolby Digital Plus can be sent over S/PDIF at lower bitrates and also it is backwards compatible with Dolby Digital because it has a core track.

Wikipedia sais Dolby Dogital Plus is possible with lower bitrates via S/PDIF and I know the Sky Soundbox is designed for Dolby Digital Plus and it is S/PIDF
The Dolby FAQ sais Dolby Digital Plus is backwards compatible.

I’m not quite sure this is the right place for such specific information. The guide should give an overview over formats and functionality as well as settings specific for the platforms we support. What you’re referring to is a Kodi setting affecting each and every platform.

The guide states this (and let me correct you there: Dolby Digital Plus can technically be passed via S/PDIF without any limitation when it comes to bitrate :wink:). Not sure what you’re referring to… Dolby Digital doesn’t offer a “core track” really like DTS does (for DTS, a seperately playable lossy track is embedded in the DTS-HD HRA or DTS-HD MA track, for Dolby Digital, it’s done differently and not as an embedded lossy track), therefore the guide clearly differentiates here.

This must be it
I can play Dolby Digital Plus from Netflix on an AVR that doesn’t support EAC3 and it plays as Dolby Digital

Are you sure your source device is not doing a re-encode to AC3 before passing things on via S/PDIF? Dolby doesn’t offer core tracks and relies solely on singular DD+ tracks for most video streaming services, so a re-encode capability is mandatory for most streaming devices. What I’d suspect is your source device will never output DD+ via S/PDIF, no matter the receiving device’s capabilites (S/PDIF doesn’t offer a back channel to communicate capabilities like HDMI does via AVI info frames).

It’s a Logitech Z-5500 from 2004, I don’t think it’s that powerful

Does it even receive DD+ tracks from Netflix? Most older streaming devices only get legacy AC3 tracks from Netflix although the very same show is streamed with a DD+ track on a different device for the exact reason you mentioned - their hardware capabilites.

The tv sais Dolby Digital Plus when the video goes on

What’s the make and model of your TV?

The Logitech Z-5500 is your sound system, so the receiving side, not the source. The source (your TV) would be doing a re-encode before passing things on via S/PDIF.

sony bravia kd-49x8005c
It passes through DTS, AC3 and EAC3
When I play a Netflix EAC3 it sais Dolby Digital Plus and the reciever sais Dolby Digital

From the manual of your TV:

The TV is by default re-encoding everything above the capabilities of its S/PDIF output before passing it on via optical… That’s what this guide is referring to when stating:

If your AVR/soundbar/TV supports Dolby Digital Plus, DTS-HD HRA and offers support for 2-channel 24 bit 192 kHz via S/PDIF, passthrough of Dolby Digital Plus and DTS-HD HRA may also work via S/PDIF.

At the same time, Dolby doesn’t offer core tracks. That also remains true. There’s a way Dolby links tracks together so it may look like it’s a core track, but it’s not a core track in the sense of what DTS does. This “linking” of two tracks is mostly only done on BD and UHD BD discs, but streaming mostly only uses singular AC3 or DD+ tracks where the latter need re-encoding for AC3 output (which most devices with this output limitation do support - like your TV).

I stand corrected, thanx for clearing that up

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No problem :wink: These formats and different functionalities are a jungle… I’ve spent hours and hours of research on this when compiling the guide’s section about different formats. This whole topic is not really designed by the industry to be simple to understand, tbh.

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3 posts were split to a new topic: Audio level setting