Smyth Research Realiser A16

[shmau]

You can find eARC to HDMI audio adapters. Cheapest will cost maybe around $100. You would connect it to an input port on the Realiser, so it may work better that way. Might be worth it to some.

 

[zdjh22]

I've found another peculiar issue (maybe a bug) with my A16. Last week I finally obtained Pink Floyd's Dark Side of the Moon Immersion box, which on the included BluRay has the prized 1973 quadraphonic mix engineered by Alan Parsons. As an aside, of the 5.1, Atmos, and this quad mix, the quad is my favorite, although the Atmos is also excellent.

This quad mix is encoded as 96/24 PCM files, 4 channels. If I use "bitstream" mode from my Oppo, or from a different Sony UDP, the A16 only detects the music as PCM 2-channel. I have to switch the Oppo to LPCM in order for the A16 to receive all of the channels, and it reports PCM 6-channel (but only has sound in the four quad corners). I can't seem to trick the Sony UDP to output PCM except for SACDs.

When the HDMI output goes to my Denon AVR, on the other hand, from the Oppo either "bitstream" or "lpcm" is correctly identified as LPCM 4.0/96/24. Likewise from the Sony (bitstream).

I would hazard a guess that the Dolby MAT decoding for the "bitstream" setting isn't handled correctly by the A16 for LPCM 4.0/96/24.

The Immersion set of Wish You Were Here includes a quad mix in LPCM, and that mix has the same problem on the A16. As with the DSOTM, an "up arrow" from the PA screen indicates "decode 2.0.0 / listen 2.0.0" when sending as "bitstream".

 

[shmau]

I'm not sure Dolby MAT would come into play there at all.

Are you sure the Oppo isn't sending out 2ch? It could be reacting to minute differences in the EDID of your AVR and the A16. To figure out that for real though you'd need to read the EDID from both and compare, or if you have an HDMI splitter laying around with a Copy EDID function (all splitters should have one) then you could use it to copy the EDID from your AVR and split the exact same signal to both the AVR and the A16 at the same time. If in that configuration the AVR still reports 4ch and the A16 2ch, then clearly the A16 is buggy. If not then maybe the A16 EDID should be modified.

 

[zdjh22]

I'm not sure Dolby MAT would come into play there at all.

Are you sure the Oppo isn't sending out 2ch? It could be reacting to minute differences in the EDID of your AVR and the A16. To figure out that for real though you'd need to read the EDID from both and compare, or if you have an HDMI splitter laying around with a Copy EDID function (all splitters should have one) then you could use it to copy the EDID from your AVR and split the exact same signal to both the AVR and the A16 at the same time. If in that configuration the AVR still reports 4ch and the A16 2ch, then clearly the A16 is buggy. If not then maybe the A16 EDID should be modified.

Great point, thanks - yes, I do have an HDFury Ultra AVR Key (a fancy HDMI splitter) lying around that may have that functionality. I’ll give that a try.

As to whether Oppo bitstream always employs the MAT encoder, I have no idea. Since it’s just a container format, it might make sense that it does so regardless of the underlying data.

 

[Sanctuary]

My M-Field amp arrived a few weeks ago, and I haven't really needed to use it much yet outside of when I have company over and want to have three people using the A16 at the same time, but right away I was noticing something that had me extremely worried.

For the longest time, I've been getting a "hum" from my previous (still main use) DAC/Amp at certain volumes that was always apparent when using analog cables with the A16. This is one of the main reasons (of two) that I just decided to start using Coax instead...which has its own problem. If I put my hand on top of the amp, the hum would go away, so I always assumed it was some kind of grounding issue with the amp.

Turns out, that's not actually the case. Despite my previous A16 not actually exhibiting this same behavior, it ended up being the RCA cables I've been using over the years.
I have an assortment of various lengths, thicknesses and plugs, but they all had one thing in common: they were all pretty inexpensive. Using the same cables from my DAC/amp to my new amp, or simply directly from the A16 to the new amp would produce a hum at the three 'o clock position and get louder as the volume increased (it goes up to five) on my new amp, which was completely unacceptable.

I've never subscribed to cable snake oil, and still don't, but I ended up buying some "World's Best" RCA cables, which were only $35, so it's not like I had much to lose.

And like magic...no more hum. Although they did pack in this bull.

 

[SpatialJunky]

That's funny!
At least they don't require the use of rocks or crystals -- or mechanical isolators (another common snake oil theme).
If you ever find yourself needing new cables, you might consider Blue Jeans Cables.
They use the same Belden we use in studio applications and they are properly terminated.
They also don't come with scientifically baseless recommendations.

 

[castleofargh]

My M-Field amp arrived a few weeks ago, and I haven't really needed to use it much yet outside of when I have company over and want to have three people using the A16 at the same time, but right away I was noticing something that had me extremely worried.

For the longest time, I've been getting a "hum" from my previous (still main use) DAC/Amp at certain volumes that was always apparent when using analog cables with the A16. This is one of the main reasons (of two) that I just decided to start using Coax instead...which has its own problem. If I put my hand on top of the amp, the hum would go away, so I always assumed it was some kind of grounding issue with the amp.

Turns out, that's not actually the case. Despite my previous A16 not actually exhibiting this same behavior, it ended up being the RCA cables I've been using over the years.
I have an assortment of various lengths, thicknesses and plugs, but they all had one thing in common: they were all pretty inexpensive. Using the same cables from my DAC/amp to my new amp, or simply directly from the A16 to the new amp would produce a hum at the three 'o clock position and get louder as the volume increased (it goes up to five) on my new amp, which was completely unacceptable.

I've never subscribed to cable snake oil, and still don't, but I ended up buying some "World's Best" RCA cables, which were only $35, so it's not like I had much to lose.

And like magic...no more hum. Although they did pack in this bull.

Is it like the Holy Hand Grenade of Antioch?
Then shalt thou burn it in for 175 hours, no more, no less. 175 shall be the number thou shalt burn in, and the number of the burn in shall be 175. 176 shalt thou not burn in, neither burn in thou 174, excepting that thou then proceed to 175. 177 hours is right out.

Who knows, maybe after 175 the hum will come back?

 

[SpatialJunky]

They probably did a study and determined that, on average, 175 hours of intermittent use puts the buyer in a position of being outside of the return window.

 

[esimms86]

Is it like the Holy Hand Grenade of Antioch?
Then shalt thou burn it in for 175 hours, no more, no less. 175 shall be the number thou shalt burn in, and the number of the burn in shall be 175. 176 shalt thou not burn in, neither burn in thou 174, excepting that thou then proceed to 175. 177 hours is right out.

Who knows, maybe after 175 the hum will come back?

My kickstarter # was 174; you’re starting to scare me!

 

[LTd head]

For the longest time, I've been getting a "hum" from my previous (still main use) DAC/Amp at certain volumes that was always apparent when using analog cables with the A16

Interesting. On my Flux Mentors connected directly from A16 I did not have such issue. Tried some different RCA cables in the past. No hum, dead silent.

If I put my hand on top of the amp, the hum would go away, so I always assumed it was some kind of grounding issue with the amp.

I had some electric current issues, i.e. when touching amp and other hand A16, I immediately felt electric current going. So I have grounded A16 using DIY cable: banana plug (connected to A16 - the same way as blue grounding wrist-strap is connected, when doing calibration with microphones) and electrical socket ground. Solved.
Something like this cable: https://av-in.com/collections/acces...cts/cordon-de-mise-a-la-terre-pour-a16-a16-se

 

[Sanctuary]

Who knows, maybe after 175 the hum will come back?

LMAO

Interesting. On my Flux Mentors connected directly from A16 I did not have such issue. Tried some different RCA cables in the past. No hum, dead silent.

Oh, my M-Field doesn't do it now that I ended up with better cables. Dead silent as well. Same with my previous amp now too. Couldn't believe it either, because I have numerous supposedly "shielded" cables, so either the shielding was poor, or the plugs were just low quality.

Really relieved though that it wasn't an issue with the power in my home, because I'm not sure that's something I could have actually fixed.

They probably did a study and determined that, on average, 175 hours of intermittent use puts the buyer in a position of being outside of the return window.

Pretty sure this is exactly the reasoning.

Now I'm curious if coaxial cables can exhibit a similar "fix" for a different problem, or if it's just something inherent with the light coming from the out going into standby mode whenever there's a pause in audio. I very frequently, but not actually repeatable on demand get a loud pop whenever I pause audio from the A16, or when changing rooms when using either of the digital outs. It's not so loud that I would be worried about it affecting my hearing in anyway, but more that it could potentially be damaging the drivers in my headphones.

 

[zdjh22]

Are you sure the Oppo isn't sending out 2ch? It could be reacting to minute differences in the EDID of your AVR and the A16. To figure out that for real though you'd need to read the EDID from both and compare, or if you have an HDMI splitter laying around with a Copy EDID function (all splitters should have one) then you could use it to copy the EDID from your AVR and split the exact same signal to both the AVR and the A16 at the same time. If in that configuration the AVR still reports 4ch and the A16 2ch, then clearly the A16 is buggy. If not then maybe the A16 EDID should be modified.

I dug out my HDFury AVR Key and did some more testing. This is an audio/video splitter intended for folks that have a newer TV supporting more recent HDCP/HDMI, and an older AVR that normally would not do proper handshaking. It allows combining the audio and video EDID tables from the two attached devices, or more simply providing a source EDID that has all audio flavors enabled.

I hooked up my Oppo 203 to the input, my Denon AVR to the Video output, and the A16 to the Audio output. There is a USB interface that allows a Windows program to display a GUI with lots of info, including the video and audio formats being received on the input.

The left image below shows that the Oppo is outputting LPCM 4.0 to the A16 when playing the quad track from the BluRay. However, the A16 only sees this as 2-channel. Simultaneously via the HDMI splitting the Denon AVR sees this as 4-channel.

I next prepared FLAC files, both 4.0 as taken directly from the BluRay, and 5.1 with dummy C/LFE as prepared from the 4.0 files with MMH. The right image below shows that the Oppo is outputting LPCM 5.1 to the A16, and the A16 sees this as a 6-channel input and renders the quad sound correctly. The 4.0 FLAC is seen by the A16 as 2-channel.

So, LPCM 4.0 received by the A16 is not interpreted correctly (the APM reports as 2.0.0), but 5.1 does work (the APM reports as 5.1.0).

I would be remiss not to mention that failure to properly decode 4.0 PCM and 4.0 MLP over HDMI by many commercial AVRs is a long standing issue. There’s even a thread or two at QQ (https://www.quadraphonicquad.com/fo...ecode-4-0-pcm-mlp-recordings-over-hdmi.26998/ for example) that list AVRs that can properly decode. For folks with systems that won’t decode properly, the standard solution is either to use a player with analog outputs and a compatible amplifier, or ripping the discs and adding phantom C/LFE channels.

As best I can tell, most AVRs, and our A16, use DSP-based decoders with Cirrus Logic or Texas Instruments DSPs, executing IP from Dolby/DTS/Auro/etc. It would be interesting to check on correlations between DSP and/or DSP board brands and AVRs that work correctly. The TI-based APM board (or software) on the A16 fails, my Denon 3600H passes.

Or perhaps the issue is related to the HDMI decoding/encoding silicon chip(s) and programming used, including EDID. I did use the nice “moninfo” utility (see https://www.entechtaiwan.com/util/moninfo.shtm) to probe the EDID tables on both the A16 and my Denon 3600H. The A16 has more extensive audio support (more varieties of PCM, for example), but neither explicitly support 4.0 PCM (assuming that’s actually a valid EDID category).

The quad tracks on the Pink Floyd Immersion discs are very commonly noted as triggering this issue, as well as some of the Rhino BluRay quadios.

 

[Cecala]

Hello Friends...

I've been testing some HPEQ measurements for a few friends recently... Most are not good and usually have a substantial imbalance... See graphs below:







As you can see... these HPEQs are far from ideal... and if used, the imbalance can and will lead to confusion. In most cases, many think that something is wrong with their machine, microphones, and or headphones. It can be very frustrating.

Even the included HD800 HPEQ that comes with the A16 has a noticeable imbalance.


Thankfully... There is an easy-ish fix.

FIRST: ALWAYS WEAR THE BLUE STATIC STRAP WHEN HANDLING THE MICROPHONES!

In my experience, the main cause of the HPEQ imbalance is from improper fit, or placement of the microphones. And this is usually the result of using the crappy yellow foam tips included with the A16. Simply replacing them with Dekoni Bulletz usually corrects most of the problem. In the past, I've recommended the Gemini 3mm versions... But as @Sanctuary suggested... the Mercury 4.9mm slide much easier onto the microphone and work just as well as the smaller Gemini version. You can find them here: https://www.amazon.com/Dekoni-Audio-Moldable-Isolation-Earphone/dp/B0721WW4DS but if you have a set of IEMs... You may already have some tips that will fit the microphones

Next is fit and placement... It's important that each microphone be placed as deep as possible into the ear canal. To do this... I put my finger in the "7" shape portion of the mic... and push the mic in as far as possible. Not to worry... It will only go so far.




Once the mics are in your ears... it is important that you gently place you headphones over your ears. Though the Dekoni tips will prevent the mics from from being pulled out of your ears... pressure on the microphone wires can change the angle of the microphone.

I have also noticed that if the microphone wires are near or touching other wires, especially power cords... interference with the HPEQ measurement will occur.

Thankfully... if these simple steps are followed... a more accurate HPEQs can be achieved... see below.



Hope this helps.

How did you graph these HPEQ measurements?

 

[Litlgi74]

How did you graph these HPEQ measurements?

I am using REW to send a sweep of a nearly flat and perfectly balanced PRIR along with the HPEQ to be measured to the A16... This allows me to isolate the HPEQ in the frequency response.

 

[sander99]

I am using REW to send a sweep of a nearly flat and perfectly balanced PRIR along with the HPEQ to be measured to the A16... This allows me to isolate the HPEQ in the frequency response.

Why would you even need such a PRIR, I thought the A16 can be put in a mode such that only the HPEQ is applied to the input signal, without SVS processing, hence no PRIR is used?