HDMI Handshake solution - Gefen HDMI Detective Plus

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JonFo

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Thought I'd share this little tidbit about how to improve the interaction with HTPC's and the Audio-Video Processors / projectors.

First, some background:

Home Theater PC's (HTPC) can do all kinds of neat things, like play all kinds of media or even games through our AVP and displays.

Now that HDMI equipped video cards are out, even audio is now carried over a single cable.

I had obtained a Radeon 4750 video card that has HDMI out and supports audio (multichannel PCM) as well as bitstreaming Dolby TrueHD over HDMI to the AVP, in preparation for BluRay and HighRez Multichannel (iTrax)from my PC.

But I had no end of problems, as every time I switched the AVP away from the HTPC input, the HTPC video would just go away, never to come back (until I shutdown).

I wasted hours screwing around with drivers, settings, etc. At the end of the day, the answer to this problem is simple: Use a Gefen HDMI Detective Plus.

For about $120 you can avoid headaches and your HTPC (which expects the 'monitor' to always be there) will never know you switched to another input.

The HDMI detective memorizes the 'good' handshake information between the HTPC and the AVP/display and maintains it even when the AVP has switched away. So the HTPC is happy that it is talking to a 'display' even when one isn't really there.

This also is the fix for other cantankerous HDMI-based devices which assume their partnered HDMI device will *always* be there and fail when it is switched away.

Highly recommended.
 
I was going to start another thread, but this seems close enough for my intent. Given that the Oppo players will convert SACD DSD stream to high-res PCM (24 bit / 88.2KHz), and given that I have a number of SACD discs, and given that I would like to try de-embedding the PCM audio stream from the HDMI signal (to feed to my W4S DAC2 which I want to try and use as a pre), I was looking at this Atlona box which strips the high-res audio from HDMI and outputs it via TOSLINK... this is perfect for my application.

Has anyone looked at this at all? I assume most folks just use the Oppo analog outs for SACD playback, or they have an HT receiver that can pull the hi-res audio off HDMI as it passes through the receiver on it's way to the display. But in my situation, this is for the 2-channel setup. No monitor.

Oh, and I do know about "satisfying" the HDMI output of the Atlona box to ensure proper HDMI management handshake. This is accomplished either by the Detective that JonFo mentions, or a f/w change to the Atlona box.

Bottom line, it's not a lot of money to try this out, but wondering if anyone has played around with this, or for that matter, even had a chance to compare DSD (via analog outs) versus PCM transcoded DSD via an outboard DAC...? Or to go just a bit further, if anyone even gives a rat's-*** ;)

Thanks

http://www.atlona.com/Atlona-HDMI-1.3-Audio-De-Embedder-with-3D-Support.html
 
Does the upconversion to 24/88.2 offer any performance you can actually hear or is it just convenient to use them in the oppo?

Tj
 
Does the upconversion to 24/88.2 offer any performance you can actually hear or is it just convenient to use them in the oppo?

Tj

It's not really an upconversion... more of a transcode from DSD to PCM. Theoritically, the result should be better-than-redbook quailty. I assume this is the same basic transcoding process that online guys like HDTracks use when generating 24/88 files from SACD releases.

Cheers
 
It's not really an upconversion... more of a transcode from DSD to PCM. Theoritically, the result should be better-than-redbook quailty. I assume this is the same basic transcoding process that online guys like HDTracks use when generating 24/88 files from SACD releases.

Cheers

You're not actually supposed to be able to do this, I believe i.e. obtain digital audio out from an SACD playing machine. Let alone at a decent bit depth/rate. If it works, Todd - respect!

Have you Googled to see if anyone else has got it working? Or is this a Todd original?:D
 
I guess it all comes down to the capabilities of the Oppo doesn't it? I have never heard of SACD coming over the digital wire... you know - Sony being hyper about copyrights etc..... but, willl the Oppo do the 'trans-coding' and then spit that out the digital connection?

Also, there have been plenty of things written about this and whether it was 'good' for the sound or not... You have the people in the camp that says 'keep it native' - and then you have others that say it sounds better to spit it out PCM..... I believe some of the Esoteric players do this actually...not all of them....and I believe some of them give you the option to either leave it native sacd or go PCM... I'm kind of in the 'leave it native' camp myself....
 
I guess it all comes down to the capabilities of the Oppo doesn't it? I have never heard of SACD coming over the digital wire... you know - Sony being hyper about copyrights etc..... but, willl the Oppo do the 'trans-coding' and then spit that out the digital connection?

Also, there have been plenty of things written about this and whether it was 'good' for the sound or not... You have the people in the camp that says 'keep it native' - and then you have others that say it sounds better to spit it out PCM..... I believe some of the Esoteric players do this actually...not all of them....and I believe some of them give you the option to either leave it native sacd or go PCM... I'm kind of in the 'leave it native' camp myself....

Right... leaving it native would be my preference, but I also like to tinker, make comparisons, and just PLAY with this stuff. The other thing is, how do guys like HDTracks get PCM versions of SACDs they sell for download? Perhaps the "buy" their content from the various labels they represent. Regardless, someone at some point had to convert the original DSD stream to PCM to generate the WAV, FLAC, or other file iterations.

At any rate, yes, the Oppo does indeed (optionally) convert DSD to 24/88 and send it out the HDMI. I think for $200 bucks, it'll be worth the experimentation.

Cheers
 
Right... leaving it native would be my preference, but I also like to tinker, make comparisons, and just PLAY with this stuff. The other thing is, how do guys like HDTracks get PCM versions of SACDs they sell for download? Perhaps the "buy" their content from the various labels they represent. Regardless, someone at some point had to convert the original DSD stream to PCM to generate the WAV, FLAC, or other file iterations.

At any rate, yes, the Oppo does indeed (optionally) convert DSD to 24/88 and send it out the HDMI. I think for $200 bucks, it'll be worth the experimentation.

Cheers

well - this would then go into your W4S Dac2 right -- at which point you would have a universal feed for all music - regardless of format.. No doubt this would definitely be interesting...

Todd - have you run the DAC direct to the amp yet? I would be curious about your impressions between that and using your prologue 3.....
 
well - this would then go into your W4S Dac2 right -- at which point you would have a universal feed for all music - regardless of format.. No doubt this would definitely be interesting...

Exactly. The Oppo would be used to play SACDs, DVD-A, and Blu-Ray audio. The Olive would continue it's duty as server where I digitally store all my CDs and also play hi-res downloads.

I'll use the DAC2 as a pre-amp of sorts... selecting SPDIF from the Olive, and TOSLINK from the Atlona de-embedder.

Todd - have you run the DAC direct to the amp yet? I would be curious about your impressions between that and using your prologue 3.....

In fact I have... and it sounded so good it convinced me to sell the PL pre :eek: and, just between us ;) I'm selling my PL Dialogue 7 monoblocks as well. As glorious as they sound, 70W only goes so far. Now that I've had some serious listening time with the CLXs, it's become clear to me that, for some music at certain levels, I can hear the soft compression when the PL amps tap out. So... I've traded all my PL gear in against a pair of Modwright KWA-150 amps. I'll bridge each to mono and this should alleviate compression in my system for all but the most ridiculous passages. I'll update my CLX thread once the Modwrights splash down. (imagine a little straight-jacketed emoticon here)

Cheers
 
You're not actually supposed to be able to do this, I believe i.e. obtain digital audio out from an SACD playing machine. Let alone at a decent bit depth/rate. If it works, Todd - respect!

Have you Googled to see if anyone else has got it working? Or is this a Todd original?:D

Hi Justin,

From everything I've read, there's no real issue with transcoding DSD to PCM. And yes, I've seen a number of threads, articles and other commentary where folks have successfully pulled this off. In fact, Atlona offers a f/w mod to their box for audio-only applications like this one where there is no video monitor (that would otherwise be required to complete the HDMI handshake).
 
Well, in the interest of interest ;) I pulled the trigger on the Atlona HD570. I called and talked to their tech guys who assured me it could handle any 2-chan LPCM up to 24bit/192KHz. They also have a 30-day money back. So if it doesn't work as advertised, or if I don't like it for any reason at all, back it goes.

It'll likely be a week from now before it arrives - I'll report back once I have something to report back on.

Cheers
 
Exactly. The Oppo would be used to play SACDs, DVD-A, and Blu-Ray audio. The Olive would continue it's duty as server where I digitally store all my CDs and also play hi-res downloads.

I'll use the DAC2 as a pre-amp of sorts... selecting SPDIF from the Olive, and TOSLINK from the Atlona de-embedder.



In fact I have... and it sounded so good it convinced me to sell the PL pre :eek: and, just between us ;) I'm selling my PL Dialogue 7 monoblocks as well. As glorious as they sound, 70W only goes so far. Now that I've had some serious listening time with the CLXs, it's become clear to me that, for some music at certain levels, I can hear the soft compression when the PL amps tap out. So... I've traded all my PL gear in against a pair of Modwright KWA-150 amps. I'll bridge each to mono and this should alleviate compression in my system for all but the most ridiculous passages. I'll update my CLX thread once the Modwrights splash down. (imagine a little straight-jacketed emoticon here)

Cheers

wow todd -- this is a huge change for you...certainly will be interesting to say the least... can you comment on the diff with and without the prologue 3? (can't believe you are unloading those dialogue 7s.....I trust your ears... but they look so dang cool!!! :) Ok- maybe I'm shallow - I can't help myself!!)
 
wow todd -- this is a huge change for you...certainly will be interesting to say the least... can you comment on the diff with and without the prologue 3? (can't believe you are unloading those dialogue 7s.....I trust your ears... but they look so dang cool!!! :) Ok- maybe I'm shallow - I can't help myself!!)

Hi Tim,

The Prologue 3 is/was extremely transparent and very quiet. I was effectively just using it as a volume control for the Olive. It didn't seem to add or subtract much at all to/from the sound so, not surprisingly, when I took it out of the path, the sound didn't seem to change much at all. The analogue output section of the DAC2 is very well designed and has plenty of drive to connect directly to the amps. The other aspect of this would be the volume control in the DAC2 versus the Dialogue 3... honestly, where some digital volume controls have trouble resolving low level passages (because they effectively just toss away bits as the volume is decreased), I could not detect any deterioration when using the DAC2 volume control at low levels. Sounded absolutely great.

So, as cool looking and neutral sounding as the Dialogue 3 is/was, I couldn't justify holding on to it when it's only function was as a volume control (and really just more connections/circuitry in the signal path). Plus, frankly, I needed to trade it in, along with the amps, to help offset the cost of the MWs.

The other thing I was never thrilled about with the PL gear... no balanced ins or outs. With CLX resolving power, any noise at all in the system was laid bare for all to hear. Single-ended interconnects are inherently more susceptible to common mode noise (whereas balanced interconnects are inherently immune). I could hear noise-floor differences in different cables I tried with the PL gear. The whole noise-floor thing should be a non-issue when I restring with XLRs (but we shall see if reality matches theory when the time comes).

Whoever said "you'll be rebuilding your system to ensure your upstream components are up to snuff when you attach CLX"... they weren't kidding!

The other thing I like about the MW amps is that they employ a floating ground on the balanced inputs... this eliminates the signal ground connection back to the pre-amp (or in this case, the DAC2). Yet another noise suppression tactic that is exactly the sort of thing I'm looking for.

Cheers
 
In fact I have... and it sounded so good it convinced me to sell the PL pre :eek: and, just between us ;) I'm selling my PL Dialogue 7 monoblocks as well. As glorious as they sound, 70W only goes so far. Now that I've had some serious listening time with the CLXs, it's become clear to me that, for some music at certain levels, I can hear the soft compression when the PL amps tap out. So... I've traded all my PL gear in against a pair of Modwright KWA-150 amps. I'll bridge each to mono and this should alleviate compression in my system for all but the most ridiculous passages. I'll update my CLX thread once the Modwrights splash down. (imagine a little straight-jacketed emoticon here)

Cheers

Todd - am I to assume you have bought these amps without a demo of them running into CLXs? Also, one bridged mono gives 650W into 4Ohms - now that just might be enough power.;)

This might sound nuts - but try just the one amp first, before doing the bridge. The reason I say this is that you might just find that the sound is better unbridged, as a friend reported when he tried it (with different amps). He ended up bi-amping.

Does the CLX allow you to drive the bass and mid/top panels independently?

I will say one thing about a Jadis JA200 driving CLXs. When I asked Pete Soderburg to turn the volume up on ZZ Top's La Grange, I wasn't sure I heard the JA200s running out of puff. And they really are pretty powerful. It was just for a brief instant as Pete backed the volume control down again.

Maybe it was just me, though.
 
Does the CLX allow you to drive the bass and mid/top panels independently?

Not without modifications under the bonnet.

BTW, wrt the issue of bridging, one of the main reasons I settled on the MWs is that they are designed specifically for bridging - with a stereo/mono switch on the back and even a dedicated set of bridged binding posts. The left and right bank of FETs are all matched to within high tolerance to ensure perfect symmetry for each waveform half.

This will be the best audio decision anyone has ever made in the history of audiophilia ;)
 
Back on thread topic... I spoke to the Atlona guys again today with a few follow-up questions and asked if there was any more documentation on just what this HD570 box was capable of beyond 16.44 and 24/88. The guy sent me a PDF which summarizes a number of tests by some third party. It appears as though this box will de-embed LPCM at basically any standard bit depth and sampling rate up to and including 24/192.

If this thing works, it will be the best audio purchase decision ever! ;)
 
Todd, interesting little box you found there. Looking forward to your report.
 
Todd, interesting little box you found there. Looking forward to your report.

It will be interesting to see what it can do. I was reading somewhere that the audio LPCM stream is actually clocked through via the video stream clock (within HDMI), so stripping the data out is a bit more complicated than synchronous capture or clock recovery from a data-only stream (e.g. S/PDIF). As such, the HDMI output of the source has to be set to at least 720p in order to guarantee sufficient b/w for max 24/192 audio.

To complicate things further, I'm now looking into digital room correction... Lyngdorf's DPA-1 looks interesting. And I know you're an Audyssey guy (or at least you've mentioned it in a positive light more than once in this forum). I've looked at Lyngdorf, Tact, and Audyssey to some extent... and have done some searching here to see what others have tried, but I'm still in data discovery mode. Any thoughts, tips, ideas wrt DRC for my 2-channel CLX based system would be much appreciated.

I would ideally like to keep all the DRC within the digital domain (i.e. no A/D or D/A conversion at the input/output of the box). Otherwise I'm not sure what good a high-end stand-alone DAC does if I'm just going to end up taking the analog output from a DRC unit, right?

Thanks
 
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This post was on a another website and seems to talking about the same issues and equipment , It looks very promising


As many of you know, there are several ways to listen to good SACD and Bluray hirez (TrueHD, DTS HD MA, 24/192 linear PCM), but they either require you to put up with the average-to-good analog outputs of a universal player like the Oppo BDP-83, trust your even-riskier jack-of-all-trades AVR/AVP to do the decoding and analog playback (assuming you have the decoders) or, most recently for us audiophiles, upgrade the analog sections to much higher levels (Nuforce NE version or full analog stage mod/replacement from Modwright). In many cases (Modwright for example) the multichannel aspects can be improved, too, These upgrades are mainly done for pristine 2 channel performance.....the subject of this new product review.

Well, what if you are like so many of us that have already dipped our toes in digital audio and have made a commitment to a stand-alone DAC, which, ipsofacto, comes with a most musical analog stage, etc? Why are we now using another DAC (the one in the Oppo, etc) for music listening. Why not treat the Oppo as a wonderful $500 transport (and movie machine) and send the Hirez music to our trusty DAC of choice.

Up until now we couldn't make that choice. But there are options. The first one (of two main options in this category) is a simple $219 stand-alone box that purports to 'de-embed" the stereo hirez music that is carried on HDMI and send it across an optical cable to our DAC of choice!!! All the while providing a simple pass-through for the HDMI to continue to our AVP's and/or display devices. Yes, I mean glorious 24/192 2 channel BlURay, or decoded SACD in 24/88.2 HiRez PCM, as well as up-to-24/192 DVD-Audio. Well....here are my first impressions:

(Note: For those who don't wanna read this....The $219 Atlona HD570 HDMI "de-embedder" has proven to be quite the little magic box that is more than worth its price...way more. )

It's called an Atlona HD570 HDMI de-0embedder. (Note: other $100-200 products are out there from different companies, most Chinese; my investigation shows they don't fully work, at least not to 24/192 or anywhere close. They have almost identical casing, but to no avail. If you want my reviewed product, it's the Atlona brand). It plugs into the wall via a typical small cell-phone-recharger-sized wallwart and has an HDMI input and an HDMI and optical digital output (and also includes an 8 channel analog output set, albeit on four miniplugs, but moot for this discussion). I connected my Oppo BDP-83 SE's HDMI into it and then passed the HDMI through on to my home theater processor and projector. The processor needs to simply be on to handshake with the HDMI signal. My $40 glass optical cable was connected from the Atlona to my Weiss DAC2 24/192-capable DAC.

My evaluation was among three sources of SACD/PCM and two sources of Blu-Ray. My SACD example was the Jimmy Cobb Quartet's Jazz In The Key Of Blue (Chesky). Sources were:
* Pure DSD via Oppo analog outs (Stealth Nanofiber RCA to Wyred4Sound STP SE preamp).
* 24/88.2 PCM via HDMI/Atlona, optical glass toslink to Weiss DAC2 toslink input (ASI liveline XLR's to Wyred pre)
* 24/88.2 purchased HDTracks file (song 6) played via Pure Music 1.45, Macbook server, firewire to Weiss DAC2 (Goldx 24k power-less fw cable) to pre

Amplification was done via the powerful and wonderfully musical Modwright KWA-150 monoblocks (in black anodized cases, gorgeous). HDMI cabling was Nordost to Atlona, Bluejeans out to AVR and pj.

My evaluation of BluRay was done with 2L's Trondheim Solsteine PCM 24/192 and AIX sampler disc PCM 24/96.
* Atlona digital optical
* Oppo analog

The SACD test was interesting in that the Oppo SE analog had a slight theoretical advantage in that it was sending Direct DSD-decoded analog vs "downrez'd" 24/88.2 on the two Weiss examples. For the BluRay test the playing field was level as to resolution of the software.

On SACD the Atlona box optical out provided the most musical of the three examples, with the HDTracks file a close second. That surprised both me and my buddy listening. We assumed the tweaked music server and pure firewire approach would win out but the Atlona/optical path was as smooth and organic sounding, yet slightly more dynamic and without any hint of top end harshness or rolloff that we were worried about (jitter from optical input and Atlona decoding). Bass energy and control were identical. The Oppo's analog output was hotter, with a slight harshness on top and an overall higher noise floor. I don't know how much of this is attributed to the Stealth cables vs Livelines, but I've not noticed the Stealths ever being harsh or tipped on top. I think the differences in sample rates/resolution were far outweighed by the Weiss's cleaner, broader bandwidth and better analog stage....at considerable more $$. The Oppo analog was no slouch, but less preferred. The HDtracks/Mac server coming in second was a surprise, but it would never be noticed without realtime a/b.

On BluRay the fight was over before the opening bell stopped ringing. The Oppo had no advantages going in and it was evident from the first notes of Mark Waldrep's wonderful acoustic recordings on AIX (24/96). The differences were large and could be discerned by all but the most musically deaf listeners. Dynamics, noise floor, tonality, air, leading edges, etc. No brainers. Then as we moved into 24/192 mode (classical selections from 2L's Trondheim Solsteine disc) the gap grew larger still. The Weiss does a very nice job with 24/192, and the Oppo Sabre DACs-to-analog couldn't keep up (even in SE mode). It was most evident in string tonality. The Oppo was midfi in comparison, although prior to this test I wouldn't have guessed.

So, I can unequivocally say that the $219 Atlona is a great little box (wish it was coax instead of optical) that can do what it says, grab HDMI audio up to 24/192 and present it, with little jitter in evidence, to a DAC of your choice. As a choice for SACD-based (albeit PCM) music, it is a clear option.

I will update this review as I listen more and find out more about its pluses and minuses. I will also post a review of another option (Shawn Fogg's 4-SPDIF board mod....same idea, just digital multichannel) in the next 30 days or so. That option will post in a separate thread.
 

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