[sander99]

About the buzz:
Some experiments that could be done to narrow down a bit where it comes from:
(Assuming it is repeatable by using that same dolby atmos movie fragment)
(Monitorring with an external headphone amp - like for example the Stax - at low volume.)
First try with soloing the speakers if the buzz maybe is in one or a few particular channel(s), or on all channels.
Try in AV Mode to check if the buzz is then in one or more of the 16 channel analog outputs (for example checking them one by one, or rather two by two, using the above so you don't need to try all outputs).
(Connecting either a normal amp with analog inputs and speakers or headphones, or a headphone amp with analog inputs and headphones, but always at low volume of course)
If it is buzzing in AV mode then most likely the buzz originates in the dolby atmos decoder (which I suspect anyway, but not sure of course), and not somewhere in the SVS processing part.

Back to normal modes for headphone listening:
Check if the buzz depends on the A16 volume control, or is constant high level.

 

[dsperber]

About the buzz:

Check if the buzz depends on the A16 volume control, or is constant high level.

Combination effect here of several issues...

Remember that both times I experienced my buzz I was in Audio Meters mode observing input levels on all channels to see if Disney (which now owns Pixar, ABC, ESPN, as well as much of the world's kid's media, entertainment venues, etc.) had actually used all 16 channels on this Dolby Atmos version of "Toy Story 2" to add anything beyond ear-level DTS-HD MA 7.1 which was used on previous BluRay releases for the franchise. The relatively hardly visible except at very close range but conceptually similar "bulging and flashing speakers" version of audio meters which has been implemented in speaker map mode (where VOLUME is also available) isn't really adequate. The audio meters presentation is ideal and extremely visible (as was the audio meters produced by EXIT on the A8, given the limitations of the A8 display).

So my instant first reaction when the buzz appeared for me the first time was to grab the A16 remote and instinctively press-and-hold the VOLUME DOWN to reduce the volume as rapidly as possible. Well, as we know, this exposes two issues:

(1) VOLUME does not work in audio meters mode. It only works in speaker map mode. If it works functionally to actually control volume but without the big bright numbers on the screen in any other mode but speaker map mode, I don't know. It certainly doesn't work at all in audio meters mode... which in this case is what I was in.

(2) VOLUME key specifically as well as all other keys on this remote are not repeat-a-matic (as it is on the Samsung version of this same remote, and as is the up/down arrow keys are on the A8 remote which control volume). So even if VOLUME functionally worked in audio meters mode (even without the bright numbers being on the screen for you to see, which would certainly not be a great implementation of VOLUME), you'd have to rapidly manually repeatedly press VOLUME to reduce the level of the buzz... if its level was controllable with VOLUME as any other audio would be.

So, while it's easy to talk theoretically about how to respond (to gather diagnostic clues about what might be causing it) should it occur again, in the absence of replacing the remote with a repeat-a-matic VOLUME key I'd certainly like to strongly urge that the VOLUME functionality be enhanced to also be facilitated while the display is in Audio Meters mode, and not just in speaker map mode. Honestly, Audio Meters mode is a terrific presentation for identifying what audio is coming from the source and what speakers should be receiving sound. It is therefore a perfectly reasonable second presentation where the VOLUME/numbers display functionality should be implemented by Smyth.

Anyway, I will do some repeat testing with my "Toy Story 2" Atmos disc, to see if I can induce it again, and if so is it again at the same point in the scene. And this time will have the Stax amp volume turned down much lower to start with, so that I don't have to have a panic response when the buzz appears. I will see if I can gather some additional clues to help Smyth fix it, and if it's consistently repeatable somehow or perhaps it just coincidentally but unpredictably occurs in some particular situation or condition.

And my testing will be confined to my own setup which does not use the A16 DAC or analog headphone outputs. I only use the optical digital output and yet clearly experienced the buzz. To me it's therefore certainly an anomaly of something inside the digital domain of the A16. Could be from a hardware/firmare defect in a DSP component, or perhaps is triggered by a software bug in the BITSTREAM decoder's use of the DSP hardware, or SVS for all these channels, or something else. But if it can occur in my all-digital A16 use, it seems appropriate to focus on the digital domain components.

 

[sander99]

I sure think it is a very strange design choice to not have the volume controls working in every mode.
(Except maybe in a special fixed-volume mode for users who intend to control the volume on their headphone amps and if applicable also their speaker amps in av-mode.)

 

[jgazal]

To mute it I unplug the left or right microphone from the Y-junction between sweeps. I set the "post silence" to 8 seconds beforehand to give me enough time. To make it easier I plan to hook up an A/B switch.

Erik, there are two limitations now.
There is no more a y-junction unfortunately.
And there is no post silence setting currently implemented.
There is no “crosstalk cancellation” playback function currently implemented via software.

 

[kh36267]

Be aware of "THE BUZZ". sometimes the unit would start outputting a buzz which could impair your hearing or damage the headphones depending on the volume setting. I also had this happen once or twice, it is really bad.
I also recommend to pull out the headphone plug when leaving the unit unattended and switched on.

appreciate the heads up.....i now make it a point to keep the headphones unpugged if not actively using them......

 

[jgazal]

Measured my stereo speakers using the analog output.
I thought it was possible at least to run an hpeq from the digital output but no, it only runs on the analog front headphone output.
I will have to build a trs to xlr cable before I can run the hpeq, since the electrostatic amplifiers I have available only have xlr inputs.

 

[bcwang]

This buzz, I wanted to discuss a bit to help try to piece together a full picture.

-When the buzz happens, is it virtualized like the buzzing is coming from virtual speakers? If so, it could be the dolby decoder having some bug that starts sending some junk data to the virtual speaker input pcm streams. If it loses all virtualization and is just a straight buzz then it seems the input to the stereo Dac stage is junk data.

-When the buzz happens, is the volume of the buzz based on the volume control level? So if you set your volume at 27 the buzz is relatively quiet? If at minimum volume the buzz still ends up being super loud, and volume doesn't make any difference, then it's again like the dac is sending junk data. I don't know if anyone actually let the buzz continue playing and tried to lower the volume to see if it made any difference. But if the volume made a difference, then the problem starts somewhere before the volume control stage of the dac. If the volume made no difference to the buzz volume then the dac itself somehow is misbehaving (I think it's a digital volume control and this is base don that assumption, if it's an outboard volume control then disregard this point)

-I think one post mentioned the buzz happened through the headphone jacks but I'm not sure it was explicitly stated.. But if that is not confirmed and it is only happening through the toslink out, then it may be something to to do with the digital output was corrupted and the outboard dac is taking this bad signal and playing back a buzz. If the headphone out also has the buzz, then it's related to something in the first two points.

-If it's possible to safely let the buzz happen with either low volume on headphone out or definitely when using external DAC, it may be worthwhile to see how to get out of that situation, such as changing a preset. It may also be good data to see if headphone B also has the problem simultaneously.

-I know someone mentioned the buzz happened when looking at the audio meter mode and listening to dolby atmos content. Was there an occurrence of the buzz that happened outside of this situation?

 

[Juy777]

This buzz, I wanted to discuss a bit to help try to piece together a full picture.

-When the buzz happens, is it virtualized like the buzzing is coming from virtual speakers? If so, it could be the dolby decoder having some bug that starts sending some junk data to the virtual speaker input pcm streams. If it loses all virtualization and is just a straight buzz then it seems the input to the stereo Dac stage is junk data.

in my case it did not sound like it is coming from virtual speakers, more like direct-in-your-face

-When the buzz happens, is the volume of the buzz based on the volume control level? So if you set your volume at 27 the buzz is relatively quiet? If at minimum volume the buzz still ends up being super loud, and volume doesn't make any difference, then it's again like the dac is sending junk data. I don't know if anyone actually let the buzz continue playing and tried to lower the volume to see if it made any difference. But if the volume made a difference, then the problem starts somewhere before the volume control stage of the dac. If the volume made no difference to the buzz volume then the dac itself somehow is misbehaving (I think it's a digital volume control and this is base don that assumption, if it's an outboard volume control then disregard this point)

i had the impression that the buzz was digital fullscale independent of volume setting, basically max volume no matter what

-I think one post mentioned the buzz happened through the headphone jacks but I'm not sure it was explicitly stated.. But if that is not confirmed and it is only happening through the toslink out, then it may be something to to do with the digital output was corrupted and the outboard dac is taking this bad signal and playing back a buzz. If the headphone out also has the buzz, then it's related to something in the first two points.

in my case i had it happen on user A HP out and also user B HP out, i did not use any digital out or other outputs

-If it's possible to safely let the buzz happen with either low volume on headphone out or definitely when using external DAC, it may be worthwhile to see how to get out of that situation, such as changing a preset. It may also be good data to see if headphone B also has the problem simultaneously.

one could attempt this using low efficiency cheap HP from walmart, you would just have to unplug the expensive HP and swap with the cheap "throwaway" HP, i will get one

-I know someone mentioned the buzz happened when looking at the audio meter mode and listening to dolby atmos content. Was there an occurrence of the buzz that happened outside of this situation?

(please "click to expand" to the right to see all of my answers)
in my case it happened outside of audio meter mode, both times

 

[audiohobbit]

I sure think it is a very strange design choice to not have the volume controls working in every mode.
(Except maybe in a special fixed-volume mode for users who intend to control the volume on their headphone amps and if applicable also their speaker amps in av-mode.)

I don't think that it's a deliberate choice, but a limitation of the software. The volume controls actually do work in some other menus (but not all as it seems), only the display in big numbers (or any display at all) is missing. You can recognize this when leaving the speaker map at a specific volume level, go to the menu, and change the volume and go back to the speaker map, then you'll see that the volume has actually changed (you'll also hear this over the headphones). Could be that it only works in the main menu though.

With the A8 it is somewhat similar. Since it has no extra volume keys, the up/down keys act as volume controls, but only when in the normal preset view. When you'r in another menu, the up/down keys scroll through the menus and can't act as volume keys.

I thought it was possible at least to run an hpeq from the digital output but no, it only runs on the analog front headphone output.

That's odd, with the A8 HPEQ is at least working with the analogue outs, haven't checked digital out, because I don't have a DAC.
Have you tried the analogue line output on the back of the A16?

 

[jgazal]

That's odd, with the A8 HPEQ is at least working with the analogue outs, haven't checked digital out, because I don't have a DAC.
Have you tried the analogue line output on the back of the A16?

Sorry, I wrote it wrong.
I haven't tried the line output on the back.
Anyway, won’t work with my setup.
Actually it is also a limitation of the amplifiers I have available.
It is easy to make a cable though.

 

[Juy777]

Regarding the buzzing noise issue, i sent email to James yesterday evening and he replied immediately monday morning (today).

They take this issue very seriously and are planning to release a firmware update within the next 24 hours to eliminate the buzz.
Apparently they dont know exactly what is causing the buzz but are still able to prevent it from happening somehow.

 

[audiohobbit]

BUZZ-occurences over headphones so far:
- dsperber (FW 1.05) using optical out and external DAC.
Repeatable with UHD BD "Toy Story 2" in chapter 22 ("When She Loved Me" song), sending Dolby True HD bitstream (probably 7.1 instead of Atmos), being in Audio Meters Display. PRIRs factory BBC 9.1.6 and combined BBC 9.1.6 with A8 type imported PRIR. STOP on the player didn't stop the buzz.
- hadron70 (FW 1.02):
No audio signal incoming, navigating through menus, machine-gun-like buzz suddenly occured.
- Juy777 (FW 1.05): multiple times, at least once randomly, when doing nothing. Once on user B HP out after plugging in HP (but could be there before pluggin in of course).

Correct so far?

 

[audiohobbit]

Regarding the buzzing noise issue, i sent email to James yesterday evening and he replied immediately monday morning (today).

They take this issue very seriously and are planning to release a firmware update within the next 24 hours to eliminate the buzz.
Apparently they dont know exactly what is causing the buzz but are still able to prevent it from happening somehow.

Ah, been writing my post while you wrote yours.
So maybe we wait for the new FW for "buzz" reports? Or, since I add the FW version I still send it to them?
I intend to send the list tomorrow to James. Still have to go through some pages in the manual to check for typos etc. (I already encountered a whole chapter that was misplaced. but overall the manual is quite good so far.)

 

[bcwang]

Yes it's for Dolby enabled speakers. You can just forget this.... They had to implent this on demand of Dolby to get the license, although those settings don't make any sense with the Realiser (even if you record some upfiring speakers you'd just record them as a top speaker, no need to tell the Realiser that it's an upfiring speaker

But what does this setting actually do in the realiser? Does it actually do nothing or does it do something? It would still be good to know what changes happen if it’s set.

 

[sander99]

But what does this setting actually do in the realiser? Does it actually do nothing or does it do something? It would still be good to know what changes happen if it’s set.

I think it does some filtering of the signal for the upfiring/reflecting dolby atmos enabled speakers (something apparently needed to optimise for reflecting via the ceiling, part of dolby processing).
You could use it if you use the A16 as a decoder-preamp with real speakers, including upfiring/reflecting speakers. And of course this filtering should also be applied when you use virtual upfiring/reflecting speakers over headphones (either applied during the measurement or during usage). But if you don't plan to do any of these things you don't need it.