Audio Processor in the IMB Server

[Mark Gulbrandsen]

Just looking over the new version of the GDC SR-1000 which has combined audio processing as well as image. They seem to have done this the right way as it can be integrated into brand new all digital systems, or retrofitted into systems with analog amplifiers. Of course the sound aspects are not nearly as sophisticated as are they in the Trinnov, but who knows. That stuff may come next.
This is undoubtedly going to be the path of the future and it has already led to the extinction of USL processors. Will Dolby be next?

[Marcel Birgelen]

Dolby's IMS3000 has a built-in audio-processor that can be activated via license and it can do Atmos as well.

Since audio-processing is an almost entirely digital affair those days, the only thing you need is a proper CPU and some software, there is almost no more need for custom-built DSPs. Eventually, you need to turn your digital signal into an analog one of course. For that, Dolby also has a solution: the DMA series amplifiers, which come in 16, 24 and 32 channel versions.

[Steve Guttag]

Yeah...Dolby's IMS3000 was first in integrated cinema processor by years (even without the C19 year). The IMS3000 can run 5.1, 7.1 or full ATMOS, has up to 1/12 octave EQ...etc.

As for USL processors extinction, you can blame COVID19 (no new sales) and a primary chip plant for Digital to Analog converters for that. To use alternate parts would likely have required redesign of the fiberglass all with an uncertain future. Furthermore, QSC, which owns the USL product line does have their DPM processors, which handles most 5.1 and 7.1 systems.

My personal opinion is that the appeal of the sound processor in the IMB/IMS will be limited. Since Dolby has been at it for years now, I wonder what percentage, particularly once they offered the IMS3000 sans audio processor (it used to be on all of them, now, as Marcel notes above, it is a licensed feature) that go for just a server versus server with audio. I can say that of the IMS3000s we've put in, ONLY the ATMOS rooms had the audio processor function activated. We have proper audio processors (mostly QSYS now) to handle the various audio functions for both DCP and other sources.

The life-cycle of a cinema server is proving to be notably shorter than that of a typical audio processor, regardless of your preference so why put the money in the most disposable piece in the booth? Dolby, with their DMA amplifier and the IMS3000 with audio CAN provide a rather low-cost and small footprint sound system. Since the audio travels via AES67, you can remote-mount the projector/server and put the amplifier(s) where convenient and there is but a singular CAT6 cable to connect all of the audio to the amplifier(s) (which come in 16, 24 and 32 channel varieties).

Yet, Dolby has their CP950, which I think will still dominate Dolby's sound processor sales over the IMS3000.

I guess time will tell on how people decide to spend their money and what risks they are willing to take putting so much in a single box.

[Mark Gulbrandsen]

Personal opinions aside, I think this is going to be dictated in the end by the chains. If they can save a buck....

[Marcel Birgelen]

Eventually, I think it will become the new standard, if we like it or not. Full digital eq and sound processing has been a thing for a while now and it has become increasingly cheap to do so. You can already centralize all processing of multiple rooms on a single Q-Sys stack and eventually, "digital amplifiers", as in amplifiers with network connectivity and built-in DA converters will become the new standard... we might even see active, network connected speakers popping up...

[Carsten Kurz]

I wouldn't want to be urged to power-up the projector 'just' to be able to have audio. Of course that doesn't count for the huge amount of plain-vanilla multiplex screens. The chains will probably love fully integrated systems - you can swap the whole server including the audio processor, and image, server and audio config can be backed up and restored in one go.

[Steve Guttag]

I don't think it will be as popular as you think. As for cost, if it is the chains, QSYS will win on that front. You can do10 screens, with ease on a CORE510. Even with two of them for full redundancy, you are still cheaper than separate audio processors in individual servers.

I'd like to see amplified speakers so one just needs to plug in the Ethernet cable (and power). As it is, with QSYS, you are only analog from the amplifier to the speaker and we've already done sites where the amps are behind the screen so those runs are short.

[Marcel Birgelen]

I think that for the costs of a QSYS system over a complex with 8 rooms or more, are mostly marginal on the entire bill, plus you can potentially save on the licensing cost on your IMS (don't know if GDC charges additional for licensing of their audio processor option). The advantage of a system is that you can easily throw in other audio sources, including PA systems and central music playout.

I'd say, the target market best served by this is are small-scale, booth-less installs that require DCI compatibility. Stuff like private screening rooms, schools, museums, etc. could save a bit on extra equipment. In the end you still need some rack space for your amplifiers somewhere though, but this may be where active speakers may make some sense eventually.

[Steve Guttag]

Marcel, don't forget, it is an incomplete solution. They (GDC) have their Audio D-A box (since, like Dolby, you can't put analog into a projector without noise) that adds into it and it, seemingly, only does 8-channels so a 7.1 system requires yet another D-A converter. If we're comparing same-same, I can likely get the break-even on a QSYS system in at under 8-screens. For instance, a CORE-NANO can handle 2-3 screens (64-channel capability) and the DCIO really becomes THE processor part per screen and that is less than an IMS3000's audio upgrade. Enough less that a pair of CORE Nanos and three DCIOs is on par with the added costs of audio into the IMS3000.

Now, if these server companies were to have an AES67 output (the IMS3000 does but it is only activated for their internal audio processor and ATMOS), then even the DCIO becomes non-required.

I'm not saying there won't be "some" appeal to the sound processor on-board but then you have speaker crossovers to contend with too. Dolby's solution, since they use the AES67 spigot can do the crossovers internally or on their DMA. How about on GDC's? It's not a complete solution and you are putting some processing on the outside.

Screen Shot 2021-04-30 at 6.44.03 AM.png
If you believe that diagram, their AIB-2000 box...external sources don't go into the server for B-chain processing...so, I guess not.

I suspect that the whole concept was due to a specific market they are in that is using the IMS3000's audio capability against them or there is a client that asked for this specific capability.

However, if you are having to do the speaker crossovers externally, some cost savings are blown there as you are either getting amplifiers with DSP in them or you are getting a monitor/crossover like the DCM series or you really anticipate low-rent theatres that use nothing but passive crossover speakers on their stage channels.

In essence, what GDC has done for their "Audio Processor" is to move the fader and EQ to BEFORE the AES3 outputs instead of after, and that is about it (from a user standpoint...sure, there is the signal generation and such). And, with this, they only have to have a check box to apply the processing or not to go between an "Audio Processor" and the standard fixed-level/no-eq AES3 outputs.

A place it might make some happy is they likely are able to add a "volume" cue that doesn't require pre-configuring all of the possibilities from 0.0-10 but merely add the volume cue and then assign the level. I don't know this for sure but that is how Dolby has traditionally done it and we have one customer where 100-steps of volume is not enough precision! (or so it seems)

I'll give GDC props for having the level adjustments in dB but kept the fader at the proper, user-friendly, 0.0-10 scale. The Audio processor portion of the SR-1000 is in the current manual posted on the GDC web site. So those that are interested should download to check out if it is a good fit for them.

[Mark Gulbrandsen]

Marcel, don't forget, it is an incomplete solution. They (GDC) have their Audio D-A box (since, like Dolby, you can't put analog into a projector without noise) that adds into it and it, seemingly, only does 8-channels so a 7.1 system requires yet another D-A converter. If we're comparing same-same, I can likely get the break-even on a QSYS system in at under 8-screens. For instance, a CORE-NANO can handle 2-3 screens (64-channel capability) and the DCIO really becomes THE processor part per screen and that is less than an IMS3000's audio upgrade. Enough less that a pair of CORE Nanos and three DCIOs is on par with the added costs of audio into the IMS3000.

Now, if these server companies were to have an AES67 output (the IMS3000 does but it is only activated for their internal audio processor and ATMOS), then even the DCIO becomes non-required.

I'm not saying there won't be "some" appeal to the sound processor on-board but then you have speaker crossovers to contend with too. Dolby's solution, since they use the AES67 spigot can do the crossovers internally or on their DMA. How about on GDC's? It's not a complete solution and you are putting some processing on the outside.

Screen Shot 2021-04-30 at 6.44.03 AM.png
If you believe that diagram, their AIB-2000 box...external sources don't go into the server for B-chain processing...so, I guess not.

I suspect that the whole concept was due to a specific market they are in that is using the IMS3000's audio capability against them or there is a client that asked for this specific capability.

However, if you are having to do the speaker crossovers externally, some cost savings are blown there as you are either getting amplifiers with DSP in them or you are getting a monitor/crossover like the DCM series or you really anticipate low-rent theatres that use nothing but passive crossover speakers on their stage channels.

In essence, what GDC has done for their "Audio Processor" is to move the fader and EQ to BEFORE the AES3 outputs instead of after, and that is about it (from a user standpoint...sure, there is the signal generation and such). And, with this, they only have to have a check box to apply the processing or not to go between an "Audio Processor" and the standard fixed-level/no-eq AES3 outputs.

A place it might make some happy is they likely are able to add a "volume" cue that doesn't require pre-configuring all of the possibilities from 0.0-10 but merely add the volume cue and then assign the level. I don't know this for sure but that is how Dolby has traditionally done it and we have one customer where 100-steps of volume is not enough precision! (or so it seems)

I'll give GDC props for having the level adjustments in dB but kept the fader at the proper, user-friendly, 0.0-10 scale. The Audio processor portion of the SR-1000 is in the current manual posted on the GDC web site. So those that are interested should download to check out if it is a good fit for them.

I don't see why the external devices wouldn't also be processed by the processor in the server. From that diagram, it appears anything going in to the server gets processed. Weather it has input specific settings for that processing is pretty simple to find out.

[Steve Guttag]

Analog 7.1 channels don't go into the SR-1000 (or Mic)...nothing analog goes into the SR-1000. Do you see a line for it? Only HDMI does (as it always has, with or without the audio processor).

[Mark Gulbrandsen]

Tje AIB-2000 is just an analog to AES Digital converter. There is nothing stopping the SR-1000 from.also processing the AUX inputs. But I will check with GDC to see if the firmware also allows each input to.have its own.processing.

[Steve Guttag]

The manuals are on line...

Nothing stopping? What inputs do you propose to use? The server has no inputs aside from SDI and HDMI. If the AIB could do B-chain facilities then it would it for ALL of the sources...in which case, what's the point of the audio processor within the server...which brings me back to why audio processing in the server isn't ideal.

Again, if they had an AES67 spigot on the SR-1000, then you have something because you can move audio in both directions and in large channel counts. But, even then I'd prefer a separate sound system. Again, the life cycles of a server are drastically shorter than the life cycles of a sound processor. There are people still using film sound processors with D-A converters feeding the "Digital" inputs. Do many of your theatres plan to pull their JSD-whatevers when their servers go (or have gone)? Doubtful.

[Gordon McLeod]

The lack of external device processing sort of defeats the usefullness of this product. And if you went with digital amps you have no facility for nonsync

[Tony Bandiera Jr]

No one has brought it up yet, but another big drawback to this processor in IMB idear is if the audio part of the IMB fails. you are now totally down on that screen. I like Steve's use of QSYS, that makes the most sense in ALL installations. I would be more comfortable going with Steve's recommendation of a CORE-NANO even on a single screen.

How about on GDC's? It's not a complete solution and you are putting some processing on the outside.

Correct, and they show the need for an external processor for such things an non-sync, alternate content audio, and a booth monitor output. How much does that AIB-2000 add to the cost, and remember that EACH screen will require one.

It is hard for me to trust a company where, in the YouTube video the projector was referred to in the first person. Was that narration a translation from bad Chinese? EDIT: Link to Carsten's thread on that evidently sentient projector: http://www.film-tech.com/vbb/forum/m...ant-projectors

As for locating the amps in the speakers, while it does have some advantages, the drawbacks outweigh them. With separate amps, a failure of a critical channel is easy to patch around without further disrupting the show. If say your center channel goes out, you have to either cancel the show, or send someone behind the screen to climb the rigging and do a repair, which takes a lot more time and is a lot more disruptive that doing a quick hot repatch in the booth (or at a behind the screen rack.) Of course, since most theatres these days do not have anyone on staff with any sort of technical skills, maybe this is a moot point. Back in my service days I was lucky to have several locations where even one of the kids on staff was sharp enough to follow my phone instructions to bandaid a show until I could get there.

The best way to sum this up is why stuff 10 pounds of in a 5 pound container when you have the ability to use two 5 pound containers?