[blub]

What filter do you mean? I'm aware of hardware which simulates it, but it costs around 2000 EUR.

[SNACKeR99]

See the plugins here, for example: https://www.pro-tools-expert.com/production-expert-1/2016/5/...

[jasonwatkinspdx]

Here's a classic reference on it: https://www.linkwitzlab.com/headphone-xfeed.htm