HDX4, is it possible?

[Delta Music Belgium]

I was reading the manual of the AVID HD I/O today and I noticed this info:

Maximum I/O Configurations

Pro Tools HD with HDX cards supports up to a maximum combination of 16 total of the following audio interfaces:

• HD OMNI (only one HD OMNI is supported in a single system)
• HD I/O (up to 16 HD I/O can be used simultaneously—requires 4 HDX cards)
• HD MADI (up to 4 HD MADI can be used simultaneously—requires 4 HDX cards)

And in the AVID HDX Card Installation Guide I noticed the same info:

In an expanded system, you should connect audio interfaces only to the first 4 HDX cards in your system.

Pro Tools HD with HDX cards supports up to a maximum combination of 16 total of the following audio interfaces:

• HD OMNI (only one HD OMNI is supported in a single system)
• HD I/O (up to 16 HD I/O can be used simultaneously—requires 4 HDX cards)
• HD MADI (up to 4 HD MADI can be used simultaneously—requires 4 HDX cards)

But on the AVID website is stated:

Work with up to 256 audio tracks with a single card system or up to 768 audio tracks with three cards. Mix up to 192 ins and outs.

192 ins and outs = 12 interfaces (12 interfaces with 4 interfaces per HDX card = HDX3)

Is anyone runnig 4 HDX cards?

Is it possible?

Did anyone try this?

I have an expansion chassis with HDX3 and some free PCIe slots left so I’m wondering if it would be possible to make it a HDX4 system...

[pm mastering studio]

Hi there,

If I'm not mistaken the max amount of cards is HDX3.

with kind regards

[Delta Music Belgium]

Originally Posted by pm mastering studio

If I'm not mistaken the max amount of cards is HDX3.

That is what I (and everybody else) always thought and that is what is stated on the AVID website.

But the point is that according to the quotes from the 2 manuals in my first post it appears to be that 4 cards are possible. It would be very strange that AVID would make a wrong statement like that. They must have tested configurations with 4 cards with 16 interaces and they must have came to the conclusion that it works. Only then AVID would write this info in the HD I/O manual and in the HDX Card Installation Guide.

So I keep wondering if a 4 card system would work…

I would like to try it out myself, but I don’t have a spare card.

[JFreak]

Maybe it's a support thing? If you have a motherboard that can take more than 3 cards and provide enough power for every one of them, I cannot see why not.

But limiting systems to 3 cards makes it more straight-forward for support -- limits tend to come from the then-current equivalent of Mac Pro, which at the time of HDX release meant 3 cards max.

[BScout]

In the early days of HDX, on Windows, it was tested to HDX4.
Can't vouch for it now or on Mac.

Windows because back then we needed an approved chipset with PCIe lanes built in and thunderbolt chassis weren't a thing yet. But haven't tried it since 2011.