Can't set an odd number of mono busses in the base architecture

[BrianParticipant]

I recently offloaded my IEM sends to a second console. This freed up 16 busses on my Avantis and so today I went into the system to change the base buss architecture. What I found is that the system requires you to use an even number of mono busses in each category. For example, if I want 5 mono FX and 5 mono groups, the system will not allow me to set this up. You can only have an even number of mono busses – ie 2, 4, 6 etc mono busses in each group. I ended up having to set up 6 mono FX and 6 mono groups in my case even though I only needed 5 of each. This obviously can quickly cause an issue because you are potentially having to burn mono busses in each category when you really want an odd number. I was forced to use 2 more mono busses than I was expecting to and this prevented to from being able to have a second stereo PAFL buss because I had to waste 2 mono busses that I really didn’t need.

I see no reason to have a limitation like this set in the architecture. It is arbitrary and it definitely needs to be addressed.

[SteffenRParticipant]

busses are always handled as pairs

[BrianParticipant]

busses are always handled as pairs

Which is an arbitrary holdover from analog days.

The Avantis has 12 FX “racks” and 42 total busses. I can set up the system to use 12 mono FX and still have 30 busses left over. I can set up the system to use 10 mono FX and 2 stereo FX and still have 28 busses left. But the system can’t let me set up 11 mono FX and 1 stereo FX? This is not a “system” limitation but rather a coding limitation that can be corrected.

I can understand if the total number of mono busses needs to be an even number. But there is no reason to demand this hold true on a FX, group, aux level.

[SteffenRParticipant]

this is a given fact by the architecture
and you will not be able to change it

[BrianParticipant]

this is a given fact by the architecture
and you will not be able to change it

Which is why I am posting this in the “feature suggestion” section of this forum. Allen and Heath has the ability to change this. I realize they probably won’t, but I can still ask for it.

[volounteerParticipant]

@brian

AH has no ability to change this in the current device.

They will consider it for the next generation depending on the value to the overall line and how it helps sales,
but architecture means you can NOT change what you currently have until you re do it all.

[BrianParticipant]

I’m sorry, but I don’t believe that it is a processing chip limitation. Here is my argument……..

It’s easiest to see it when talking about FX racks. The Avantis has 12 FX racks. I can have 12 mono FX and still only use 12 busses. This proves that audio is in fact being routed through the FX racks one of two ways. Either it is true mono (not some form of stereo mixed down to mono) or it is stereo, but the “extra” channel does not need any processing power and therefore doesn’t count towards your buss count.

I can also have 10 mono and 2 stereo FX which shows that stereo FX busses are not using two FX slots.

But for some reason I cannot have 11 mono and 1 stereo? That makes no sense other than the fact that Allen and Heath programmed it that way. That doesn’t mean it cannot be changed however.

I realize it is a real limitation of the current system. But it is a limitation of how Allen and Heath wrote the code to interact with the processor, not the processor itself.

[volounteerParticipant]

@brian

Guess we will need to have an AH engineer give us the definitive answer.
We can only infer what we think they can do and how they do it.

I still suspect that when you look at the overall big systems view, that even if it could technically be done, the meta considerations will say that it can not be done and that other ways to use AH resources would take priority. I am not convinced that technically it could be done so do hope AH would give a definitive answer about their architectures and designs.

[Nicola A&HKeymaster]

The ‘architecture’ in an FPGA based mixer is not exactly set in stone. Indeed, it could be changed with firmware. However, changes to the FPGA code of the core would take significant time, test resources, and have many implications on the structure of Scene memories and Show files. So while there is nothing wrong in suggesting this feature, it is unlikely to ever be top of the list for Avantis development I’m afraid.

[volounteerParticipant]

@nicola

As a systems architect I would say that depends what you call THE architecture for a SYSTEM.

Overall THE architecture includes many many items beyond hardware, software, & firmware.

[CameronProAudioParticipant]

As someone who just took delivery on the Avantis yesterday, I found this limitation very disappointing as well. In my humble opinion, it should be bumped up on the priority list. The cut sheet says “FULLY CONFIGURABLE MIX ARCHITECTURE,” and that’s actually not the case. 42 sounds like a lot of busses, but it’s really not that many when you start adding on stereo matrices and groups. Losing an extra bus here and there adds up fast when you are wanting to only consume a mono bus but wind up consuming 2 instead. It’s not ideal.

At my day job, I work for a broadcast video tech company where most of our products are Xilinx FPGA based, so I can appreciate the complexity of making alterations to the core architecture of them. It’s not easy. But we do it a lot to accommodate relevant and important customer requests. These seems like a pretty important issue, at least to me, because you’re not truly able to fully configure the busses as desired – one of the main reasons I purchased the desk.

Thanks.

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