DSP Optimization

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DSP Optimization

Post by mausmuso » Fri Jul 06, 2018 9:15 pm

Hi There,
I have been working for sometime now on a midi switchable mixer.
I was aiming for a 24 channel mixer but have run into dsp connection problems.
I then decided to make a 16Channel version before going back to the 24 Ch one.The 16Ch version works in SDK but has problems in SCOPE XITE.
I was wondering if anyone could provide some advice on DSP optimization for bigger devices?
Loading the device without setting DSP ID's it loads on DSP 18.
I have tried placing the device on DSP 7, but it makes no difference.
Any help would be appreciated
1vu16ChMixer2.png (185.34 KiB) Viewed 1783 times
1vu16ChMixer.png (187.25 KiB) Viewed 1786 times

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Re: DSP Optimization

Post by mausmuso » Sat Jul 07, 2018 6:06 pm

Ok no takers?
A bit more detail might help.
When loading the mixer to Scope XITE, I get an error 'Cannot load Mix1 module',
There are a number of Mix 1 modules in the design, but I think I just reached a DSP limit.
I set the voices attribute of Ch16 to '0' and it loads, which sort of confirms it is DSP limitations.
I tried setting the DSP ID of the mixer to DSP7, but that did not fix it.
My questions are:
- When optimizing, do you start by allocating a specific DSP to the top level module (i.e. the mixer itself)? or
- Do you start with lower level modules (e.g. individual channels)? or
- Should I ferret out the 'Mix 1' module and set those?

- If I set the top level module to (say) DSP 7, would I then look to set lower level modules to DSP 8, 9, etc, or does it make more sense to follow the 'slots' and set them to DSP 11 and 15.

This optimization is doing my head in, any assistance or advice would be gratefully received

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Re: DSP Optimization

Post by jksuperstar » Sat Jul 07, 2018 7:13 pm

From way back I remember (not from experience) that DSPs could be assigned relative to one another, and the STM mixer channels are scattered across DSPs 7-10 to pull off the 32 and 48 channel mixers.

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Re: DSP Optimization

Post by valis » Sat Jul 07, 2018 11:52 pm

This is correct from my memory, as you can keep things on groups of 8 (in addition to stereo pairs) to insure that your mixes are phase coherent when something is multitracked. I started just using micromixers across most of my projects for this reason, but this mixer looks interesting in regards to our recent discussion on Bigmixer etc in another thread. WHen you have more progress I suggest finding that post and posting screenshots for feedback and discussion...

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Re: DSP Optimization

Post by mausmuso » Sun Jul 08, 2018 2:13 pm

Thanks guys,
I think I am beginning to see a way forward to ensure phase coherency across channels is managed and correct loading, at least in XITE.

I think the thread you mentioned was the one the inspired me to start building this particular mixer in the first place.
I will post something there for comments.
The mixer is designed such that the relevant channel page opens when you move one of the fader at the bottom of the mixer, or when it is controlled from a external controller or sequencer.
I am trying to get the majority of the functionality of a 2448 mixer into a single panel with dynamic midi controlled views.
All of that works., just need to optimize it and figure out the best way to setup parameters and presets for this configuration.
I want to finish the 16 Ch version and then go back and complete a 24Ch version.
Optimizing looks like a fun and frustrating challenge

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