can anyone link here a clear detailed scheme to build a TRS cable with 25 - 30 DB pad to wire a recorder line output to any mic in on reflex?

we are working on a corporate project, with basic interviews requiring a canon 5d and a lavalier and a boom, the bag with sound devices 664 is going to be so heavy and cumbersome so I thought to use a Tascam dr100 and wiring it directly into the canon 5d



the line output impedance on the tascam dr100 is 200 ohm, how much is the canon 5d mic input impedance?

You could just buy an off-the-shelf commercial attenuator like this....

https://smile.amazon.com/dp/B000ZLX2TU

Or, if you want to make one (with a few pennies worth of resistors) built into a connector, one of the better references for building a pad is Rick Chhinn's website:

Uneeda Audio - Build your own attenuator pads (http://www.uneeda-audio.com/pads/)

I need to know the precise impedance of the canon 5d mk3, what scheme is the right one considering we are relating to a TRS unbalanced stereo connection?

I use cables like this one for connecting the mini-trs line out of audio devices to the mic input of dSLR's and other recorders.

https://www.bhphotovideo.com/c/product/906960-REG/kopul_ach4_25mon_line_to_mic_attenuator_cable_with.html/BI/2855/KBID/3801 (https://www.bhphotovideo.com/c/product/906960-REG/kopul_ach4_25mon_line_to_mic_attenuator_cable_with.html/BI/2855/KBID/3801/BI/2855/KBID/3801)

That one above has a headphone output Y, but you can also get them with just a straight connection without the headphone jack.

I have just purchased this one

https://www.ebay.it/itm/SAA40-Stereo-Audio-Attenuator-40dB-convert-line-to-mic-level-filmmakers/182838875603?hash=item2a920bd5d3:g:EKQAAOSwajRZbGAI

Let us know how it works out. I had not seen that brand and variety of boxes.