ive tryed a few stereo/delay/reverbs that cause Correlation problems.
I use a meter to monitor, but still getting problems or is it to Mono everythin?

 

The answer below depends a lot on source material of course, but here's been my findings so far;
There are a few things that can help adjust this, not necessarily solve quickly, you will have to mix back and forth to get something good for both the stereo and mono medium. Each of these solutions have their own caveats:

https://polyversemusic.com/products/wider/
Free plug that basically applies a special comb filter pushing out certain parts of the spectrum on both sides, benefit is that it will fold back to its original source near perfectly in mono, but you cant be creative in how it spreads into the stereo field. For the most part this stops phase cancellation issues, but as mentioned before still has limitations in how organic the spread of sound is.

Second would be using mid side EQ from one of the many plugins on the market, Pro Q2 springs to mind, using the mid/side setting (basically compensating your mids for sides so when it folds to mono, more of the material is audible). I find the caveat is that you cant go extreme with this setting without making stereo sound loud at inappropiate times. You could also use eq notches in the left/right mode to perform a similiar effect as the wider plugin with more manual control, but ive already listed the caveats of that.

There are also mono making plugins that can make a specific part of the spectral field mono, such as bass (as these sets of frequencies usually have the most damaging effect when phase cancellation occurs). Plugins such as NUGEN's monoizer come to mind. It has a linear setting which tames some of the cone effect it produces in non linear mode. This can sometimes leave your stereo field rich with not so bad of a dimishing shimmer when turned to mono.

Another method is using a mono/ or 50 mono/50 stereo send for your reverb, then using wider or the left right eqing method for a clean sum when coming to mono.

Avoid using pseudo/micro delay plugins sparingly if at all. Causes so many unsolvable issues in mono.

You can also spend some time crafting a preset in your reverb plugin of choice that has a better chance of folding to mono, but you will need to look at and be able to breakdown what the parameters of your reverb are doing to alter the stereo field (requires a decent bit of experimenting.)

 

see https://docs.google.com/spreadsheet...rXsk7rfD-94yuL6LiwQ0QCzOYn2wlDLZhNhz6/pubhtml

 

You can prevent delay corr issues by raising the delay time. and reverb issues by raising the pre-delay time. Also narrowing the low feqs, if any, helps. But with high reverb amount this will always be an issue to some extend.