Important ! Do NOT phase test with the 'dynamic mixer' !!!

Tips and advice for getting the most from Scope. No questions here please.

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Shroomz~>
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Important ! Do NOT phase test with the 'dynamic mixer' !!!

Post by Shroomz~> »

While testing a new mixer that sharc & myself have been working on, it has become very clear to me that the 'Dynamic mixer' is completely unreliable for phase testing & possibly even unreliable for certain mixing tasks.

For phase testing devices if you're beta testing or whatever, use 'Phase Fix' for phase inversion as it seems to work very well indeed.
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astroman
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Post by astroman »

yes, it seems - as everything in this context 'seems' ...
one day this way - next day a different play
at least I wasn't able to detect any specific pattern behind this (imho all mixers suffer from it in one or the other form, if an inaccuracy shows up).
the funny thing is... it doesn't always (see above) ;)

cheers, Tom
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Shroomz~>
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Post by Shroomz~> »

You're right that things seem to occur or happen randomly on Scope, but from the tests i've done, that only 'seems' to be the case (repeatedly) with modules which are NOT assigned to load 'on same dsp' (like the dynamic mixer for example)

Basically, the dynamic mixer is most likely not set to load on 1 dsp. Why would it be?

All I'm saying without airing too much dirty laundry is ... don't use the 'dynamic mixer' for phase inversion & testing purposes as it is NOT reliable from what I can tell. One minute it might be phase coherent, the next it's not.... :wink:
Liquid Len
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I don't know but I've been told

Post by Liquid Len »

Interesting. The Dynamic Mixer is the only mixer I never use, because it was the only one I had a lot of problems with. It would just 'die' on me, it would be properly cabled, signal going into it, and suddenly the meters wouldn't report anything, and I wouldn't be getting any signal in or out. I'd allocate another mixer, and run some cables into it, it would show that signal was indeed coming from this or that source - but the Dynamic mixer wouldn't show anything.
voidar
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Post by voidar »

Yes, all devices that dynamically allocates DSP resources will have a life of their own when it comes to sample-accuracy. This even counts for the STM 24 and 48 mixer too. Those mixers save DSP resources when some channels are disconnected.
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Shroomz~>
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Post by Shroomz~> »

Yes, basically it's a smart algo that distributes those dynamic devices. Just not smart enough it seems.
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