Tailoring tweeter output

Recently listening nearfield and find the ribbon tweeter too hot. trying to decrease out put from 8khz and up.

Thanks

I used to listen with grills off. Now I prefer the sound with the grills on. With the grills on I hear the music. The speaker becomes more seamless as if the speaker grill is the first stage of room treatment.

Sure, you might hear more detail in some area of the sound without the grills, but it be at a price.

I see you've spent alot of time optimizing your set-up positioning. Covering the tweeter with some material in addition to the grill might work, but there will probably always be a trade-off. You might try less toe-in and move the speakers closer together to compensate. Another option is to try some different cables.

The Ribbon tweeter has very wide dispersion so toe change will not work. The 3-5Khz region will drop before attenuation of the tweeter.

I am adverse to cable tuning to decreased 8-12khz output. Any cable that accomplish this would limits bandwidth.

After looking at pictures of your system I see the problem.
You are set up on the short wall. Your speakers are too close to the side walls.
Can you arrange your room so your system is on the long wall. The sound will be much more pleasing.
The room is a complex part of the system.