How to set the delay locator to measure a subwoofer in Smaart [GSwSST29]

After you have practiced measuring a full-range speaker, the next step is to measure a subwoofer in Smaart. It turns out to be a little more tricky, but I've got some ideas to help you.
___
___
___
___
___
Be friendly
___

I love to geek out about the physics of sound. This channel focuses on the growing opportunity for live sound engineers to improve their confidence and consistency through the understanding of the principles of sound system design and optimization. My goal is to make this channel upfront and honest about my success and failure, so you can learn from both.

I am always open to suggestions and feedback so please comment on this video or contact me through my site.

[fronbasal]

This was by far the most intuitive video about delays I could find on YouTube. Thanks for sharing this publicly, a great resource! ❤

[stefanmplayer]

Hi Nathan, thank you so much for making all these video’s publicly available! They are a great help for someone like me who’s relatively new to using Smaart for actual system tuning both to acquire new concepts and as a reference since I tend to forget some things every now and than due to not doing this on a daily basis🙏🏼

[ClubmanKarvin]

For those who did not know where the wrap around 10 milliseconds came from just like me. Frequency itself vibrates 100 cycles per second (100Hz). Therefore 1 Cycle should take 1/100 seconds to complete. While 1 second = 1000 milliseconds. 10ms is the time for frequency 100Hz to complete one cycle.

[Whats_Your_Purpose]

Nathan, would it be possible to just extend you xover temporarily to 1000hz or so to get a better lock from hi frequencies thru sub?

[anggarrahudhi]

after knowing the delay of 20ms. isn't that 20ms entered into the digital sound processor delay?

[cscrignaro]

Ahhhh, I just finished calibrating my surround room and just seen this video. Ended up setting the LFE to 0 delay so that my graphs weren't all crazy. I'm mostly concerned with the magnitude trace, so I think it is okay if the coherence is slightly off. Do you think I should recalibrate the LFE with the correct delay setting? But I'm also not looking for a specific cross-over frequency since the LFE channel is it's own channel. What do you think?

[dominikkriss]

Hi Nathan, is there any reason why you are pointing measurement mic to the ground in around 45 degree? I was wondering about mea. mic placement when alligning sub to mains, so far i used to just lay it on some foam on the ground.
my consideration:
- on stand, pointing to ground at 45deg, tip nearly touching ground - getting mainly reflections of ground, no direct sounds
-on foam, on ground- 50/50 reflections and direct sound (for me it feels like the most natural usage)

- on stand, pointing up at 45deg, tip few cm above the ground - getting mainly direct sounds, reducing reflections of ground

I think it does not matter when measuring just subs, but it may have significant coherence impact when measuring also mains.
what do you think about mic placement?

[lowbass]

Hello Nathan, every X32 has the .85 ms delay? I wonder because I have a weird situation, my subs physically are behind the mains, physically .35cm, after smart alignment I have .90cm (overlap at crossover point) instead of the physical .35cm ..., does smaart take in consideration the board and the processor delay ? I am not using smaart delay, just reference and that’s it.