[JMOParticipant]

This issue was created by the pink noise generator on the console. Not sure how your phantom delays happened!

Sorry,
Jeremy Moffitt

[JMOParticipant]

The Mic did not move for any of the screen shots using the RTA, all 3 of the pics would be identical if it were a reflection or a sub-optimal room (mixes 5-6. 7-8. 9-10). The pictures of the RTA are not very useful, expect to illustrate what was missing from what I originally heard in 2 of the mixes. For the rest of the photo’s, thereon I actually just went directly into my Smaart interface to get the best reading possible, so no mic involved. This was the most sure way to avoid any skewed results, I was just being a dumb dumb in the morning.

Cheers,
Jeremy Moffitt

[JMOParticipant]

The Left side of the screen is using a reference from a MR1 Audio Generator. Its comparing a direct signal from that unit to a signal which has split from that unit, to the console, and routed to every output on the desk. I can find the delay time between the direct source and the measurement source (which is the console output) and then compare every output to that. I repeat the same steps using the on board pink noise generator and see what results I get (right side of the screen). The bottom right hand corner is showing that the phase of output 6 is unaligned with output 5. 5-6 is a stereo pair and that waveform should be the same. The other picture is just like an RTA, I can see the level of every frequency I need there, you can see the Turquoise one (5-6) has a massive drop around 8kHz which is the odd alignment I heard, the LF is still present which is what made me suspect a latency issue originally rather than a full phase flip. 9-10 also did this, colored in blue. The “Stereo Outputs” pictures really just show what I heard when I was testing some cable at the shop, it made me check if the pin out was correct on the cable and then gave me quite the run around trying to figure out what was going on.

I’m no wordsmith, but it appears there’s a filter that has its phase unaligned from the rest of the source, some weird stuff is going on that I wish I could explain but I myself am not there yet with smaart to really dig into that, I’ve got the basics.

What I take from this; if I was using this handy tool to time align a rig and a room, I may be getting skewed results and if I was in show and this happened that would make my day really bad. I found this in the shop, I’m super happy about that!

Cheers,
Jeremy Moffitt

[JMOParticipant]

Hello all,

Today I set up Smaart and have taken some screen shots. I’ve attached the screen shots so you can see for yourselves.

It appears the on-board pink noise generator is suspect to creating phase issues within outputs on the console. The mix outputs themselves are actually not coherent in relation to one another. For example on the QU16 and the QU24 (tested one just to be sure), Mix 1 and Mix 5-6 are not aligned but Mixes 1, 2, 3 and 4 are the “same” alignment. I don’t use the QU series frequently enough to say if it really matters or not that separate mix outputs have different phase alignments, its not a large format desk, but I can say it is very good news that the stereo outputs do share the same phase.

At the end of the day, if you’re carrying a QU16 or something for a traffic desk at a festival or arena, don’t use the generator to Smaart your rig. Makes me want to go run and buy my own tone generator right now!

Learn something new everyday.

Cheers,
Jeremy Moffitt

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[JMOParticipant]

I reset the console and updated the firmware. No eq, no delay on the outputs, the two problems are on stereo outputs as well. As far as I know any EQ/delay on an output on these boards are linked. Either way, there is none in use today!

[JMOParticipant]

I don’t know that a visual representation of the latency is going to help me in this instance, unless the amount of latency pointed me in a certain direction. However, because winter months have fallen upon us, I may just bust out Smaart tomorrow and take some measurements for the heck of it.

Thanks for the responses so far!

Cheers,
Jeremy Moffitt

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