Spotify and SR or matrix decoding?

[Leo Enticknap]

The DMA8+ enables upmixing as so, and the same options are also available for inputs 2 and 3 (BNC connectors that can take either AES3 or consumer S/PDIF), and 4 (Toshiba Link):

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If the automation cable is in place, its interaction with the CP650 is semi-automated for some functions (for example, selecting a given preset on the CP650 automatically changes the DMA8+'s input to a linked option), but I couldn't give you the full details without re-reading the manuals.

But despite its age, the DMA8+ remains a useful tool. Used but OK ones are still in demand for applications such as drive-ins (AES3 from an IMB goes in, and 5.1 or 7.1 goes out to a mixing board for downmixing to 2.0 for broadcast), and the one we're discussing, namely the ability to upmix from 2.0 and send the output into any processor that will accept a multi-channel analog input. Whenever we acquire one (usually traded in following an upgrade) and confirm that it is fully functional, it is usually resold very quickly.

[Frank Cox]

Apparently VLC can do some kind of stereo upmix as well, though I have no idea how well (or if) it works.

I never knew doing that was a thing. I guess it's kind of like colourizing old b/w movies....

[Ryan Gallagher]

I'm not even sure the DMA8Plus utility app is installed on our utility laptop. I'll be curious to see how ours is routed and configured, especially considering we only use it in film mode now. Considering it never leaves film mode, I doubt it was contributing anything previously to the upmixing, so I'm guessing the 650 has some pro-logic capabilities too.

[Ryan Gallagher]

Follow up: Datasat has previously told me i'm on the current version of the AP20. However I don't get "Decoder" option/button/menu enabled on my analog non-sync formats (although I do see where it appears now on the setup screen). So no Neo6 or other up mixing from those RCA inputs. My original read of the manual seems to be accurate.

I do have still the Matrix Decoder select-able to push Audio to other channels, and it does engage the subs and surrounds, with the one of our recent Dolby EQs swapped in it doesn't sound horrible.

Seems if I want the AP20 to do the Neo6 or other modern upmixing I need to get our music piped in through one of the digital inputs (or rope in the DMA8plus to pre up-mix stereo analog input to 8chan)

I'll have to set up the AP20 digital input method sometime soon to compare what adding a real decoder does. I put more effort than I should into these walking themed playlists, just trying to get them sounding great too. ;-)

[Carsten Kurz]

True, Neo:6 is only available for digital NonSync sources or HDMI (stereo) audio, irrespective of AP20 firmware or hardware version. While matrix decoding and bass enhancement can be enabled for the two analog NonSync inputs, Neo:6 is for more capable in upmixing of stereo than the matrix decoder.

[Ryan Gallagher]

True, Neo:6 is only available for digital NonSync sources or HDMI (stereo) audio, irrespective of AP20 firmware or hardware version. While matrix decoding and bass enhancement can be enabled for the two analog NonSync inputs, Neo:6 is for more capable in upmixing of stereo than the matrix decoder.

I went in early enough yesterday to setup and try a new HDMI input and Neo6 to 7.1 upmix yesterday from a booth laptop. It does sound so much better than either of the analog options we were previously using. What I created was essentially a copy of our Oppo Blu-Ray channel, but then flipped the HDMI number and Neo6 settings to "Music" and 7.1 upmixing,

Most recent method, my NonSync-Matrix preset was doing weird things with the choices between what to put in left versus right. That might have had to do with our analog console upstream. Console output would look balanced L+R, but Matrix decoder would put almost everything in the R channel on some tracks.

But Neo6 is great, the amount it deploys the LFE when set to "music" mode perhaps a bit much for walkin vibes, but that can be adjusted on the channel gain.

GOTCHYA

I did however encounter a serious AP20/Windows glitch when HDMI is coming direct from a Windows PC that is keeping HDMI Music from being ready for primetime. On two machines tested (a WinVista and Win11 variant), when switching formats on the AP20, and coming back to the HDMI Neo6 one, Windows does not *always* resume (resume is perhaps the wrong word, something interrupts) sending audio over HDMI to the AP20. In settings everything will be set like it is, and you can see activity bars on the output in software, but nothing on the AP20. At least until you change to another audio out on windows and then toggle back.

Probably solvable with an EDID type device to keep the HDMI connection Windows sees from fluttering during format changes. At least I assume that is what is happening. Neither PC ever claimed to lose their external display, but the audio not recovering between formats consistently was the issue. I assume it's on the windows side cause a toggle between outputs there fixes it, but it could very well be something the AP20 is not handshaking correctly too.

The head scratcher is windows never "reverts" to a different output, it acts like the original is still working. Maybe it's a spotify bug or something and I need to test with other software too.

Another gotrchya is, as you said, it only works with 2.0 streams, if you send 8 channels via the PC configuration, even if only L+R are active, it won't decode or upmix that bitstream.

IDEAS

Everyone who might run film in our booth is too used to the Mackie for audio ducking/fading music etc. Asking them to set an AP20 volume other than 7.0 and fade from the cinema knob is a workflow change I don't trust, and requires some additional format configuration, automation, or diligence to not blast the music (unless we duck it in the format levels).

As such I might look into a USB hardware knob that can control the PC output volume, or consider dis-embedding an analog signal from the HDMI stream to use for booth monitoring, cause in my testing using existing EQs and Levels copied from another format, our booth monitor was only "reasonable" when PC volume was ducked very low, and fader knob at like 5.0 or some combination. Or normal has been to have PC gain set at full and trim it on the Mackie, running fader at 7.0, with a separate little booth monitor coming from the mackie, because the main film monitor barely is audible at those input levels.

While HDMI/Neo6 works and sounds great, overall it's got some kinks in our current booth flow to spend some time considering.

[Ryan Gallagher]

Another perk of the original non-sync methods via the mixer, is that the stage mic could be left hot if desired for impromptu announcements from stage, they could just talk over the music if they had to and the operator was away from the booth. Not a very clean way to implement that alongside HDMI audio unless we use the AP20 mic input instead, or toy around with an embedder that will take an analog source and matrix it into the HDMI signal.

I suppose an audio interface could also do it if we switched to SPDIF away from HDMI, but our AP20 SPDIF is currently set as a alternative/backup for the Blu-Ray source.

[Ryan Gallagher]

Just troubleshooting out loud...

Last night I tried a passive dummy hdmi display adapter with pass thru, while the OS did recognize the ability to send 2CH audio to it, the AP20 did not recognize a bitstream. With my output reset hack going direct, I was still able to run a show with Neo6. But it was clunky.

Next time I'm gonna try an active HDMI Audio disembedder. At least the audio passthrough should be supported. And I may split the analog disembedded signal into the mixer. That way either AP20 format is valid and we can still use the booth monitor via the mixer. Trick will be can a single PC volume and fader level be made workable for both format presets. TBD.

I also still need to rule out Spotify as the cause for the interruption when switching formats. I did notice last night the interruption occurs when switching AWAY from the Neo6 format. Because if I do my PC output device toggle hack before switching back to Neo6 format, everything works as expected when switching back.

[Tony Bandiera Jr]

Ok, I've been following this in silence as the overly convoluted solutions are played out, and not working too well so far.

The easiest solution? (and one that can be cheap if you source the hardware used online).

Get a consumer A/V receiver to do all of your media audio decoding. See the pics of a screening room I did here: https://www.film-tech.com/warehouse/...911&category=1

I used the DENON receivers in all of my alt content applications and they work without a hitch, you can easily set different levels by channel for EACH source, and IIRC you have adjustable delay to compensate for latency. (I don't recall ever having any latency issues to correct for anyway.)

Most Denons will decode Dolby AND DTS audio streams. Even the old analog 2 ch RCA inputs can decode to Dolby Surround with LFE. I used the ones with rs232 control ability to tie to Crestron or AMX automation. One model was the AVR-3801Ci (IIRC the Ci indicates RS232 capability)

ANY good brand of A/V receiver will work, so don't feel like you HAVE to use a Denon. As long as it has a set of analog outputs, HDMI inputs and some analog inputs that can go to the decoders, it will work better with less fuss than what you're doing now.

Edited to add: And Middle Atlantic makes custom rack mount shelves for a lot of odd gear, including the entire Denon line of A/V receivers. Includes the shelf, hardware and custom cut face panel, in brushed black aluminum or painted textured black.

Ryan contact me privately if you want to go this route if you need help.

The most you'll have to bother with is switching your 6/8ch analog inputs to the AP 20, and even that is a easy and cheap fix. (I used the old (and very cheap) DB25 switchboxes built for computers. They switch all 25 pins and don't add noise or crosstalk. I have also built custom switchboxes with relays that take either a 12vdc input or a contact closure. I can still whip up the relay boards on request.

[Ryan Gallagher]

Ok, I've been following this in silence as the overly convoluted solutions are played out, and not working too well so far.

The easiest solution? (and one that can be cheap if you source the hardware used online).

Get a consumer A/V receiver to do all of your media audio decoding. See the pics of a screening room I did here: https://www.film-tech.com/warehouse/...911&category=1

I used the DENON receivers in all of my alt content applications and they work without a hitch, you can easily set different levels by channel for EACH source, and IIRC you have adjustable delay to compensate for latency. (I don't recall ever having any latency issues to correct for anyway.)

Most Denons will decode Dolby AND DTS audio streams. Even the old analog 2 ch RCA inputs can decode to Dolby Surround with LFE. I used the ones with rs232 control ability to tie to Crestron or AMX automation. One model was the AVR-3801Ci (IIRC the Ci indicates RS232 capability)

ANY good brand of A/V receiver will work, so don't feel like you HAVE to use a Denon. As long as it has a set of analog outputs, HDMI inputs and some analog inputs that can go to the decoders, it will work better with less fuss than what you're doing now.

Edited to add: And Middle Atlantic makes custom rack mount shelves for a lot of odd gear, including the entire Denon line of A/V receivers. Includes the shelf, hardware and custom cut face panel, in brushed black aluminum or painted textured black.

Ryan contact me privately if you want to go this route if you need help.

The most you'll have to bother with is switching your 6/8ch analog inputs to the AP 20, and even that is a easy and cheap fix. (I used the old (and very cheap) DB25 switchboxes built for computers. They switch all 25 pins and don't add noise or crosstalk. I have also built custom switchboxes with relays that take either a 12vdc input or a contact closure. I can still whip up the relay boards on request.

Thanks Tony. The separation of AV processing is an interesting approach. Definitely seems justified in your example where there is a whole compliment of various video sources to contend with (including VHS).

As for our case, we only use a Blu-Ray Oppo for discs, or sometimes our 4K consumer player if the if UHD was the only option. And then Spotify and/or stage microphone.

As the AP20 has 4 HDMI inputs, and plenty of others, seems there should be a more direct workable path than roping in a consumer AV receiver. But it does seem like having a piece of equipment to be first in line before the AP20 is likely necessary for the Windows/Spotify HDMI source.

Will definitely consider your approach if nothing elegant works out otherwise. I can see the benefits... Just not quite there yet. There is a stated goal of cleaning up the DCI rack before next season and retiring some of the non-used equipment still in it, maybe that will be the time to consider adding an AV receiver option for one option on up-mixing of AV sources.

Edit: One nuance of our ask is we are not asking for a piece of gear that can decode Dolby and DTS music streams, but rather do it's own upmixing to 5.1 or 7.1 from 2CH PCM bitstreams regardless of which encoding is present or not. Spotify does not officially support any immersive audio formats. Most modern surround capable AV receivers can probably do some form up-mixing, but it is built into the AP20 also, so seemed logical to start there trying to make it work.

[Tony Bandiera Jr]

Thanks Tony. The separation of AV processing is an interesting approach. Definitely seems justified in your example where there is a whole compliment of various video sources to contend with (including VHS).

As for our case, we only use a Blu-Ray Oppo for discs, or sometimes our 4K consumer player if the if UHD was the only option. And then Spotify and/or stage microphone.

As the AP20 has 4 HDMI inputs, and plenty of others, seems there should be a more direct workable path than roping in a consumer AV receiver. But it does seem like having a piece of equipment to be first in line before the AP20 is likely necessary for the Windows/Spotify HDMI source.

Will definitely consider your approach if nothing elegant works out otherwise. I can see the benefits... Just not quite there yet. There is a stated goal of cleaning up the DCI rack before next season and retiring some of the non-used equipment still in it, maybe that will be the time to consider adding an AV receiver option for one option on up-mixing of AV sources.

Edit: One nuance of our ask is we are not asking for a piece of gear that can decode Dolby and DTS music streams, but rather do it's own upmixing to 5.1 or 7.1 from 2CH PCM bitstreams regardless of which encoding is present or not. Spotify does not officially support any immersive audio formats. Most modern surround capable AV receivers can probably do some form up-mixing, but it is built into the AP20 also, so seemed logical to start there trying to make it work.

Thanks for replying. To discuss the points I bolded in order:

HDMI: Those outputs went directly to a Kramer Video Switcher/Scaler (Which stripped HDCP or at least performed perfect handshakes every time) then the HDMI (or Component, on non DCI projectors) video went out to (in my case) A CP2210 or CP2220 projector. The audio was fed to the Denon via Toslink or Coaxial Digital.

The upmixing: The Denon would either decode a selected specific Digital format, OR it would default to a matrix decoding of a standard 2ch PCM. If the PCM wouldn't decode properly, you can still feed it a 2ch analog audio via the same source's inputs and it would do the matrix decode.

The AP20 built in: It obviously cannot do the task you need it to do, and it will not allow ready switching between multiple sources like the intermediate A/V receiver will. It's all about speed, efficiency, ability to switch on the fly without glitches and, with the help of an external control system (AMX/Crestron, etc.) the easy use of a SINGLE button to execute any source selections along with projector and sound format changes/decoding.

Those things were, to me, (especially dealing with the UCI screening rooms, a multi purpose facility like yours) an electronic Swiss Army Knife, and worth every penny. They could do most anything with the audio and do it well and for a LOT less money that some other processors out there. And they were extremely reliable. The bonus is you could also use the tuner if necessary. (I deliberately grounded out the FM and AM antennas on the ones at UCI to keep the kids from playing around with it.)

[Ryan Gallagher]

The AP20 built in: It obviously cannot do the task you need it to do, and it will not allow ready switching between multiple sources like the intermediate A/V receiver will. It's all about speed, efficiency, ability to switch on the fly without glitches and, with the help of an external control system (AMX/Crestron, etc.) the easy use of a SINGLE button to execute any source selections along with projector and sound format changes/decoding.

Well at least the theory behind the AP20's feature set is that it CAN do it (can even switch between 4 HDMI audio/video sources if our booth had been planned out that way). Can it do it cleanly with proper handshaking without additional pieces of gear? Perhaps not, that seems to be the rub I'm encountering with the PC source.

Those things were, to me, (especially dealing with the UCI screening rooms, a multi purpose facility like yours) an electronic Swiss Army Knife, and worth every penny. They could do most anything with the audio and do it well and for a LOT less money that some other processors out there. And they were extremely reliable. The bonus is you could also use the tuner if necessary. (I deliberately grounded out the FM and AM antennas on the ones at UCI to keep the kids from playing around with it.)

I can definitely see the swiss army utility of an AV receiver. Got vintage mix-tapes you want to play... no problem. Host an improptu VHS party? Also no problem. With minimal or zero configuration fuss in your cinema processor. Want to spin some vinyl in the booth... you might need a phono preamp accessory, but basically no problem. lol

We do plenty of weird stuff here, but most of it falls under the context of live events or live event components of screenings, which falls to a fully independent audio department using the live PA and console, outside of projection's domain. It's pretty rare such demands are made of pure film events, which is where the booth equipment is the only option. Though flexibility is definitely the MO in general, so would be a welcome addition.

[Ryan Gallagher]

Although to be fair, I’m probably giving the AP20 A/V format switching feature set more credit than it is due. It was never going to be equivalent to a “seamless switcher” or even a “clean switch” router. But an AV receiver is not either. Need another layer if you want quick/clean switching, such as the Kramer in your example.

When a show calls for multi source seamless stuff here they just rent a broadcast switcher from me.

Gather you were not even sending video to the Denon for switching, unless purely as a side effect of sending it the hdmi audio, but it sounds like you avoided that and used alternative digital audio routing, since the receiver has plenty of those inputs too.

[Tony Bandiera Jr]

Although to be fair, I’m probably giving the AP20 A/V format switching feature set more credit than it is due. It was never going to be equivalent to a “seamless switcher” or even a “clean switch” router. But an AV receiver is not either. Need another layer if you want quick/clean switching, such as the Kramer in your example.

When a show calls for multi source seamless stuff here they just rent a broadcast switcher from me.

Gather you were not even sending video to the Denon for switching, unless purely as a side effect of sending it the hdmi audio, but it sounds like you avoided that and used alternative digital audio routing, since the receiver has plenty of those inputs too.

That is correct, I didn't send HDMI to the Denon. The model I mentioned had sufficient toslink inputs for the sources I used, and the VHS just went in analog via the RCA jacks. I had no issues with latency and the switching of both audio source and video were handled by the AMX system via RS-232.

I have become quite adept at writing the code for the AMX systems, even have a saved code set to talk to Crestron via RS-232. It was made easier by the fact that all of the screening rooms I did AMX for used pretty much the same equipment packages for projection, sound and alt content. And it is easy to edit my standard code to account for and additions or changes to a particular room. Also, thanks to the relative abundance of used (but still very functional) legacy Axcess hardware, I could outfit a room at less than half the cost of the newer NetLinx hardware (thankfully the NetLinx servers and touchpanels can still interface with the legacy Axcess hardware.)

[Tony Bandiera Jr]

Another perk of the original non-sync methods via the mixer, is that the stage mic could be left hot if desired for impromptu announcements from stage, they could just talk over the music if they had to and the operator was away from the booth. Not a very clean way to implement that alongside HDMI audio unless we use the AP20 mic input instead, or toy around with an embedder that will take an analog source and matrix it into the HDMI signal.

I suppose an audio interface could also do it if we switched to SPDIF away from HDMI, but our AP20 SPDIF is currently set as a alternative/backup for the Blu-Ray source.

An alternate (and very inexpensive, around $160.00) mixer for your non sync and stage mic application is the Behringer ZMX8210 https://www.behringer.com/product.ht...lCode=0602-AAH

The mic 1 input has "ducking" which mutes the music from inputs 7 or 8 (Both stereo RCA) while someone is talking, then fades it back up when they stop. I use this one extensively for my announcing PA systems as it avoids "dead air" during my shows. All inputs and the three outputs (L, R, and AUX mono which is handy for booth monitoring) are balanced/unbalanced mini euroblock connections. Inputs 7 and 8 (toggling pushbutton selectable) are RCA unbalanced. It is very quiet and performs great.

Even if you are (as I'm pretty sure you would be) using a larger mixer, you could use the Behringer in front of two channels of your existing board (set to accept line level balanced signals) and now you have a separate, more flexible control of your stage audio and non sync that can be pretty much "set it and forget it." (A big plus for my mx tracks as they often use the system when I am not there.)