Hi-res and streaming - again.

[Nevalti]

I've been happy with the Parasound. I don't think the Bryston was that much smaller physically.

The model I auditioned was a Parasound A21. It was certainly an impressive amplifier which I probably would have been very happy with but it was simply too big.

The dimensions of the Parasound A21 were 438 x 488 x 194 compared with the Bryston 4BSST 432 x 401 x 133. By my calculations that is 4,147cc instead of 2,304cc - i.e. getting on for double the volume!

[Nevalti]

You guys are now talking about kit which is considerably more expensive than I wish to spend right now.......

............This review of Karajan's Mahler 5, reissued on BRD, suggests that Blue Ray audio does have some similar "issues" to SACD, with a requirement to use HDMI to get a hi-res output, otherwise the audio output will only be the same as a conventional DVD ...............

1. As long as you buy good enough equipment second hand, you can usually sell it for the same or more; therefore it is 'cheap'. Just this week I made a profit of £800 selling a high quality but redundant pre-amp.

2. I have never tried one but you can buy an HDMI to DIGITAL AUDIO converter quite cheaply. £15 or thereabouts. Obviously you need one with a SPDIF or TOSLINK output and certainly not just the R/L audio output type. Try searching eBay.

[Dave2002]

1. As long as you buy good enough equipment second hand, you can usually sell it for the same or more; therefore it is 'cheap'. Just this week I made a profit of £800 selling a high quality but redundant pre-amp.

2. I have never tried one but you can buy an HDMI to DIGITAL AUDIO converter quite cheaply. £15 or thereabouts. Obviously you need one with a SPDIF or TOSLINK output and certainly not just the R/L audio output type. Try searching eBay.

Point 1 - interesting. I could do with making that sort of money ...

Point 2 - There may be HDMI to digital audio gadgets on eBay (I looked) and also on Amazon, but if we are discussing hi-res then it seems questionable that any will do the higher bit rates needed. There are AV amps/receivers which will take in HDMI, but I don't know what quality level they are at.

Here is one such splitter gadget from Neet - http://www.amazon.co.uk/Neet%C2%AE-C.../dp/B00H8T1DJ8 but there's not enough information re the SPDIF/Toslink quality levels. There are indeed cheaper ones, but I suspect to get a quality device for this particular audio application will require more expenditure.

Here is another one, with some details of the audio, but still not hi-res, I think - http://www.amazon.co.uk/LingsFire%C2.../dp/B00QND5N1O

[Nevalti]

Hello Jayne, I knew you were into HiRes and hoped you would be an experienced streamer with lots of advice to offer. Sadly for me you are only playing directly, which for me works brilliantly, but my wife is less impressed by a laptop in the corner of the room. That, plus the quantity of music on my NAS make me keen to find a satisfactory streaming solution for all my music.

Reading your comments on the difficulty of finding suitable recordings to compare made me wonder if I am kidding myself. I thought I had found a simple solution to that problem but you have worried me now. Having bought a few HiRes downloads, I made a copy of them which I down-sampled to 16/44.1. Listening just to those copies without making a careful A/B comparison, they sound absolutely fine - just like a CD in fact, as they should. By feeding my Benchmark DAC2 simultaneously with the HiRes original and my down-sampled version, I was able to simply switch inputs all through the recordings so that I had an instantaneous A/B comparison.

Frankly, some parts of the music were indistinguishable but in some others the difference was very clear. Instruments and voices really do sound more like REAL instruments. The self-deceptive illusion of 'being there' is much easier to maintain. The absolute clincher for me was the female choir in 'Neptune'. Their ethereal, smooth tone in HiRes sounded almost gritty when switching to 16/44.1. That difference is presumably present all the time in CDs but we have few 'pure' sounds like that to ram it home; usually that relative grittiness is hidden in the complexity of the music. The opening of Borodin's 'Steppes' would probably show it up well IF I had a HiRes version. I recall being initially put off by that sort of thing when CDs first appeared but I have obviously become used to it over the years.

Another very clear demonstration of the advantage of HiRes was making my own 24/96 & 16/44.1 recordings of me playing a guitar sitting between my speakers. When played back, the illusion of live sound is far better with 24/96 than it is with 16/44.1. I have only tested three people so far but each one could confidently tell which was the 16/44.1 recording because it didn't sound 'real'. None of them could confidently distinguish, blindfolded, between me playing live from the 24/96 recording. It became guesswork.

[Stunsworth]

If you buy a hi-res recording from Qobuz you can also download the 'normal' 16/44.1 version (or the AAC or MP3 version for that matter). If you are using iTunes just be careful to rename the album before downloading it a second time in different resolution, otherwise the two albums will be mixed together into one. I usually rename hi-res albums by adding something like "(Qobuz 24/96)" to the end of the album title.

[Nevalti]

Point 1 - interesting. I could do with making that sort of money ...

Point 2 - There may be HDMI to digital audio gadgets on eBay (I looked) and also on Amazon, but if we are discussing hi-res then it seems questionable that any will do the higher bit rates needed. There are AV amps/receivers which will take in HDMI, but I don't know what quality level they are at.

Here is one such splitter gadget from Neet - http://www.amazon.co.uk/Neet%C2%AE-C.../dp/B00H8T1DJ8 but there's not enough information re the SPDIF/Toslink quality levels. There are indeed cheaper ones, but I suspect to get a quality device for this particular audio application will require more expenditure.

Here is another one, with some details of the audio, but still not hi-res, I think - http://www.amazon.co.uk/LingsFire%C2.../dp/B00QND5N1O

My assumption currently is that it is a simple wiring job for the HDMI to Coax digital and that you could do that yourself with a wire stripper etc and not use any box. IF that is the case, there should be no quality issues. IF that assumption is wrong then getting decent quality is extremely difficult as you need a high quality DAC with an HDMI input.

A Toslink transmitter is, apparently, a very simple thing and they are claimed not to degrade the sound. My experience is that a coax connection is always fractionally better than Toslink but that is not the point you raise. The question is - what is in the box? Simple wiring or cheap electronics. Someone here will know.

[Dave2002]

My assumption currently is that it is a simple wiring job for the HDMI to Coax digital and that you could do that yourself with a wire stripper etc and not use any box. IF that is the case, there should be no quality issues. IF that assumption is wrong then getting decent quality is extremely difficult as you need a high quality DAC with an HDMI input.

A Toslink transmitter is, apparently, a very simple thing and they are claimed not to degrade the sound. My experience is that a coax connection is always fractionally better than Toslink but that is not the point you raise. The question is - what is in the box? Simple wiring or cheap electronics. Someone here will know.

You may be right, but there's still an issue about what is output across the HDMI cable. Using HDMI 2 it should be possible to pick up a DSD stream - providing it's not blocked, and feed that into a DAC with DSD input. Alternatively, a PCM stream can be output, but some devices only output 24 bits/48kHz - which is not considered hi-res by some people, though better than CD quality, which is "only" 16 bits/44.1 kHz.

I don't know enough about HDMI - but I think what gets transmitted depends on the equipment and manufacturer.

See http://en.wikipedia.org/wiki/HDMI and particularly the table with green and red data.

[Stunsworth]

My assumption currently is that it is a simple wiring job for the HDMI to Coax digital and that you could do that yourself with a wire stripper etc and not use any box. IF that is the case, there should be no quality issues. IF that assumption is wrong then getting decent quality is extremely difficult as you need a high quality DAC with an HDMI input

I don't think it's as simple as that. I believe that the HDMI protocol involves the sending and the receiving device exchanging a 'handshake' and that if this isn't forthcoming the sending device refuses to send any information. Presumably this is done to prevent piracy.

So I think the 'splitter' device described above will have some active electronics in it.

[Nevalti]

You may be right, but there's still an issue about what is output across the HDMI cable. Using HDMI 2 it should be possible to pick up a DSD stream - providing it's not blocked, and feed that into a DAC with DSD input. Alternatively, a PCM stream can be output, but some devices only output 24 bits/48kHz - which is not considered hi-res by some people, though better than CD quality, which is "only" 16 bits/44.1 kHz.

I don't know enough about HDMI - but I think what gets transmitted depends on the equipment and manufacturer.

See http://en.wikipedia.org/wiki/HDMI and particularly the table with green and red data.

I think I may have understood 10% of that Wikipedia page! It does say this though....

"For digital audio, if an HDMI device has audio, it is required to implement the baseline format: stereo (uncompressed) PCM. Other formats are optional, with HDMI allowing up to 8 channels of uncompressed audio at sample sizes of 16-bit, 20-bit and 24-bit, with sample rates of 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz and 192 kHz.[16][46] HDMI also carries any IEC 61937-compliant compressed audio stream, such as Dolby Digital and DTS, and up to 8 channels of one-bit DSD audio (used on Super Audio CDs) at rates up to four times that of Super Audio CD"

If it is 'required' to implement baseline stereo PCM, one would have thought that all devices would output PCM. The DSD output, nice though that would be, is just an option.

(Posted before I saw Stunworth's comment - which certainly has a ring of truth about it)

[Dave2002]

I don't think it's as simple as that. I believe that the HDMI protocol involves the sending and the receiving device exchanging a 'handshake' and that if this isn't forthcoming the sending device refuses to send any information. Presumably this is done to prevent piracy.

So I think the 'splitter' device described above will have some active electronics in it.

Looking into this further, I think you are right. From the page I mentioned earlier I found a link to this http://en.wikipedia.org/wiki/High-ba...ent_Protection on HDCP, which indicates that the audio channels are encrypted, and that transmission across the HDMI link of any protected material will be dependent on both the sender and receiver being HDCP compliant. A splitter must decrypt the audio, and also at the same time ensure that high resolution content is not transmitted to a non HDCP compliant device. This may mean blocking the transmission, or reducing the quality level (for audio, resampling at a lower sampling rate, and possibly also changing the bit depth). There are apparently no constraints if an audio splitter creates an analogue output signal.

It is, I suppose possible, that a splitter itself could behave as a non compliant HDCP device, in which case all downstream devices, even if HDCP compliant, would be treated as non compliant. HDCP compliant upstream devices would not output any high quality audio or video data to such a device.

There are flaws and problems with HDCP. It may present just one more way for things to go wrong, or not work as the end user hoped.

Edward Felten wrote "the main practical effect of HDCP has been to create one more way in which your electronics could fail to work properly with your TV," and concluded in the aftermath of the master key fiasco that HDCP has been "less a security system than a tool for shaping the consumer electronics market."

[richardfinegold]

There are some high end DACs that will take HDMI for audio only. The 2 that I know of are made by PS Audio and NAD. Reportedly they are low jitter and I presume are meant to work with Blu Ray. My Oppo B105 also has an HDMI input.

[Dave2002]

I did at least get round to trying some hi-res tracks. I went to the HDTracks site, and there's a free sampler. Took me a little while to find out how to force output at a higher samplng rate - not sure why this is in the Midi utility for OS X, but it is!

I wasn't sure what to use as a player, but audacity seemed to work. The Smoke and Mirrors percussion track sounded OK.

I did not immediately go "wow, this is what I've been missing all my lfe!", so I remain on the fence re the benefits. It could just be that recordings which sound really good are better recordings, and the quality has nothing to do with sample rate or bit depth.

Maybe I'll jump to one or the other side of the fence in due course.

[Stunsworth]

I agree that manually having to change sample rates etc. in the Midi/Audio program is a pain, that's one of the reasons I use the Aurirvana playback software, it handles the change automatically.

[neiltingley]

Ayre AX7 integrated is a good buy. PM me if you would like to buy mine!