Motor speed on spool and notch filter question

I recently made large changes to the X8 build, due to off the chart vibration on the 3rd accelerometer regardless of the change the vibe continued so suspecting the issue was with the cube I swapped it with an older cube and set to work using the help previously provided by @xfacta and @dkemxr for notch and rate … Two main questions are

  1. when spooling up the copter the props immediately start spinning (at a higher rate than I would like) on arming… how can I slow this down?
  2. I added the first notch (logs attached - pre notch and post notch) looking at post notch fft should I add a second notch (lower props?)
    also if anyone would care to look at the attitude and give comments as on prior post it is suggested I tune manually Thanks again
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Hello @mbuilds

About Question 1, you can fine tune your MOT_SPIN_ARM, you can lower it in 0.01 steps to find a suitable value for you.

I can’t help with Question 2, @xfacta and @dkemxr are the guys regarding this.

Thanks! will adjust next time out.

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From here:

I would choose 112Hz as the center frequency, 1/2 as BW, all else you set looks OK. I’m not sure it will make much difference from the 122Hz you set but that’s what it looks like to me. You don’t need a 2nd notch.
Tune looks pretty decent. I guess you have a reason to set the Rate(s) I lower than P?

Thanks Dave… Attention to detail is a must, I was thinking the minor intervals were 20Hz , will definitely make that change.

Concerning the “I” being lower, I was not done tuning but its a slow process so I will try increasing I and see how it reacts. I know I asked this question before as I am still a novice, though getting better at manually tuning. If someone can give a better or more accurate than my reasoning below , Please do, I am all ears! I

In (most?) PID loops the “I” will be less than “P”… I have great success in tuning the alexMoss gimbal boards using a method where you first determine to power, then set P increase but avoid oscillation, next set “D”. with a gimbal you want to avoid wobble, im guessing with drone I want one snap back when I twitch its axis, once set then add the “I” to help correct overshoot if value is too high it creates overshoot…
BTW if tuning a alexmos gimbal I strongly suggest this video PERFECT PID tuning for Alex Mos Basecam Gimbals - Yuri Method (long Alexmos tutorial simplebgc) - YouTube

Actually in most Arducopter control loops they will be equal. At least in my experience that’s been true. I’m sure a Dev can give a reasoned answer why this doesn’t necessarily have to be the case but it’s worked out well for me. Manually tune P, typically using Transmitter based or Live tuning, and then set I equal is what I do.

Thanks Dave… It will likely end up the same here also, I know every autotune I have done sets these the same. I would appreciate knowing the explanation from Dev