HD Audio Codes (PS3 question)

noodler

Hello all,

For Blu Ray with the PS3, to obtain HD sound do you actually need an amp which can decode HD audio? I heard the PS3 can do the encoding for you so a normal DD amp would be sufficient and there would be no real benefit in one that can decode DTS-HD for example.

Any thoughts?

Idleater

noodler wrote: »

For Blu Ray with the PS3, to obtain HD sound do you actually need an amp which can decode HD audio?

No, but you do need an AVR that can decode 7.1 LPCM streams. There are a few of these on the market, but most AVRs nowadays have the HDAudio decoding chips onboard.

If you were looking at this for a cost saving, then you are out of luck. There might be a few LPCM Decoders on the second hand market, but they are generally higher end manufacturers (eg the Rotel 1069 [I have one of these] and the Audiolab 8000AP amongst others), so the prices even second hand will be a lot more than an AVR with the on board decoding features.

IMO there is a difference between functionality and function but that is another discussion

noodler

nereid wrote: »

No, but you do need an AVR that can decode 7.1 LPCM streams. There are a few of these on the market, but most AVRs nowadays have the HDAudio decoding chips onboard.

If you were looking at this for a cost saving, then you are out of luck. There might be a few LPCM Decoders on the second hand market, but they are generally higher end manufacturers (eg the Rotel 1069 [I have one of these] and the Audiolab 8000AP amongst others), so the prices even second hand will be a lot more than an AVR with the on board decoding features.

IMO there is a difference between functionality and function but that is another discussion

You can set the PS3 to output in bitstream or LPCM. I thought most amps could read PCM? I mean the PS3 HAS TO decode the audio so surely there are moe than a couple of amps which are compatible with the PS3 and HD audio?

EDIT: Actually I think I saw what you said about the LPCM decoding issue somewhere else but how do amps (say one that can do DD and one that can do DD HD) do with the decoded sound the ps3 issues them since the majority of them wouldn't have LPCM decoders?


I had been looking at this for example

http://www.richersounds.ie/asp/product.asp?ObjectID=938&Mode=0&CategoryID=3&sub=24&productid=897


Actually, what about this? Has no HD decoding but seems to accept LPCM (or whatever you said!) and is only 150

Idleater

noodler wrote: »

You can set the PS3 to output in bitstream or LPCM. I thought most amps could read PCM? I mean the PS3 HAS TO decode the audio so surely there are moe than a couple of amps which are compatible with the PS3 and HD audio?

You can apparently set the new slim ps3's to bitstream HD Audio streams, but I have the Phat so I have it decoding the audio and outputting it as LPCM.

PCM (Linear L or otherwise) is the unpacked sound, Bitstreamed HD Audio, is the zipped up (compressed) variant.

LPCM is the HDMI 1.1 (and perhaps 1.2) way of transferring audio. It was designed with "source decoding" in mind as opposed to "sink decoding" where it is done in the AVR a la HDMI 1.3.

Any amp that is HDMI 1.3 should be backwards compatible with HDMI 1.1, so therefore the amount of amps that support LPCM is actually quite high, but this is different from those designed only with this in mind. We will then get into a nice discussion about noise and complexity in circuitry, again, a very interesting topic that perhaps a thread in its own right.

noodler wrote: »

EDIT: Actually I think I saw what you said about the LPCM decoding issue somewhere else but how do amps (say one that can do DD and one that can do DD HD) do with the decoded sound the ps3 issues them since the majority of them wouldn't have LPCM decoders?

Processors that do audio en/decoding work by computing analog voltage signals from streamed 1's and 0's. What this means is that the Audio stream from a CD, SACD, DVD, BR or any other digital source must be unpacked from the media and transferred. This is your DTS, Dolby Digital, TrueHD, Master Audio, etc.

These are unpacked into PCM digital "waves", which can then be converted to analog waves and sent to the amplifier and thence to the speakers.

You can see from this, that one can either feed the processor with raw data, or pre-unpacked data, depending on what it is expecting. Depending on what the source can do, and what your processor can accept, you have various options for getting your HD Audio.


When you talk about DD and True HD (one being 'ordinary' and the other being 'High Def') you are not comparing like with like. The HD audio stream as LPCM requires that the decoder can accept 8 streams of 192khz audio, plain DD DTS at the maximum rate is 96khz, so in order to get the full HD Audio bit rate, you need one designed for that.

noodler wrote: »

I had been looking at this for example

http://www.richersounds.ie/asp/product.asp?ObjectID=938&Mode=0&CategoryID=3&sub=24&productid=897

That should do you perfectly. it decodes all the HD Audio bitstreams, and with a quick google people have it working with LPCM (and asking questions that I forsee you coming across if you compare bitstream to lpcm )

Ask any other questions re the above answer, I'm not sure I covered all your points as best as I could!

noodler

nereid wrote: »

You can apparently set the new slim ps3's to bitstream HD Audio streams, but I have the Phat so I have it decoding the audio and outputting it as LPCM.

PCM (Linear L or otherwise) is the unpacked sound, Bitstreamed HD Audio, is the zipped up (compressed) variant.

LPCM is the HDMI 1.1 (and perhaps 1.2) way of transferring audio. It was designed with "source decoding" in mind as opposed to "sink decoding" where it is done in the AVR a la HDMI 1.3.

Any amp that is HDMI 1.3 should be backwards compatible with HDMI 1.1, so therefore the amount of amps that support LPCM is actually quite high, but this is different from those designed only with this in mind. We will then get into a nice discussion about noise and complexity in circuitry, again, a very interesting topic that perhaps a thread in its own right.




Processors that do audio en/decoding work by computing analog voltage signals from streamed 1's and 0's. What this means is that the Audio stream from a CD, SACD, DVD, BR or any other digital source must be unpacked from the media and transferred. This is your DTS, Dolby Digital, TrueHD, Master Audio, etc.

These are unpacked into PCM digital "waves", which can then be converted to analog waves and sent to the amplifier and thence to the speakers.

You can see from this, that one can either feed the processor with raw data, or pre-unpacked data, depending on what it is expecting. Depending on what the source can do, and what your processor can accept, you have various options for getting your HD Audio.


When you talk about DD and True HD (one being 'ordinary' and the other being 'High Def') you are not comparing like with like. The HD audio stream as LPCM requires that the decoder can accept 8 streams of 192khz audio, plain DD DTS at the maximum rate is 96khz, so in order to get the full HD Audio bit rate, you need one designed for that.


That should do you perfectly. it decodes all the HD Audio bitstreams, and with a quick google people have it working with LPCM (and asking questions that I forsee you coming across if you compare bitstream to lpcm )

Ask any other questions re the above answer, I'm not sure I covered all your points as best as I could!

I appreciate the help, my questions were a bit of a mess I know!

Tbh , because the PS3 did the decoding I was hoping top get something cheaper than 507 (it felt a bit of a waste!). You don't reckon there something cheaper that can accept the LCPM do you? Probably not says you since you said I'd probably have no luck if I was trying to skimp!

Idleater

noodler wrote: »

I You don't reckon there something cheaper that can accept the LCPM do you?

The one you listed above (onkyo 507) is €279 on Richer sounds (or £250 whichever you prefer) and the Pioneer 819 is €255 / £229 and is also listed as doing the same decoding.

I'm not sure how much cheaper you think you can get, because even if you get something for <€200 you are only saving €50 or something. In that price bracket, everything is very competitive so you will find it hard to find a bargain that does every feature for less than the competition.

If you were comparing a 1069 to an 8000 (see above) where you have the possibility of saving €500 depending on where you source it, then sure, I'd be looking around.

noodler

Okay so what do I need to look for to see if a given amp can accept LCPM even if it doesn't decode HD signals?

Basically you reckon theres F all chance of a cheaper amp (no hd decoders) that could accept the LCPM the PS3 can output?

I may just go for a DD/DTS amp to begin with.

The Ritz

@nereid,

Thanks for the superb explanation.

@noodler,

I'd agree with nereid here, I don't know how much cheaper you are likely to get a reasonable starter AV receiver - €255 for the Pioneer or €279 for the Onkyo is pretty outstanding value for money.


Ritz.

Idleater

noodler wrote: »

Okay so what do I need to look for to see if a given amp can accept LCPM even if it doesn't decode HD signals?

Any amp that will decode a 7.1 LPCM stream over HDMI @192khz. This is equivalent to HD Audio version over HDMI 1.1.
Here is a completely incomplete list of amps and processors that satisfy this requirement.

noodler wrote: »

Basically you reckon theres F all chance of a cheaper amp (no hd decoders) that could accept the LCPM the PS3 can output?

I may just go for a DD/DTS amp to begin with.

How cheap do you want to go? Like the ritz says, €250 is pretty cheap IMO. Fair enough, you will get a DTD/DD amp cheaper - the cheapest ones on Richersounds are £150/€170 which gets you HDMI switching and DD/DTS decoding.
If you bitstream from the PS3, i think it will downmix the HD Audio to the best DTS can do (which is pretty good), so your saving is €70-€100 which might make a difference in your speaker budget, and would be an adequate starting setup.