BbAltered
I would like to have a transparent limiting plug-in on my main mix bus to prevent clipping.  I'm not interested in maximizing volume, only in preventing digital "overs".  And free if possible.

Any limiter will be adequately transparent when used in this manner. "Transparency" only becomes a relevant term when you're asking the plugin to fundamentally alter the dynamics of the music through aggressive gain reduction and "smart" release calculations that hopefully disguise what's happening.
 
Catching the occasional peak will almost never cause a noticeable audible change or distortion. If it does, then you need to go back into the mix and lower that peak.
 
What you're after is a limiter that performs the one essential, basic function of any limiter, which is to guarantee that no peaks ever exceed a specified value. Any of the above-mentioned plugins will do that reasonably well,  as long as your maximum amplitude is reasonable.
 
However, very few of them can guarantee no overs in every scenario. For example, if your material is hitting 0dB (or higher) on a regular basis and average peaks are only slightly below that, then it's unrealistic to expect any limiter to be "transparent". That'd be expecting a plugin to do your work for you.
 
Bottom line is don't sweat it. Use whatever strikes your fancy, and just don't push it. Don't set your brickwall to 0 dB and don't set your volume so high that the limiter is constantly engaged. Sounds like that's your plan already.
 

bitflipper

BbAltered
I would like to have a transparent limiting plug-in on my main mix bus to prevent clipping.  I'm not interested in maximizing volume, only in preventing digital "overs".  And free if possible.

Any limiter will be adequately transparent when used in this manner. "Transparency" only becomes a relevant term when you're asking the plugin to fundamentally alter the dynamics of the music through aggressive gain reduction and "smart" release calculations that hopefully disguise what's happening.
 
Catching the occasional peak will almost never cause a noticeable audible change or distortion. If it does, then you need to go back into the mix and lower that peak.
 
What you're after is a limiter that performs the one essential, basic function of any limiter, which is to guarantee that no peaks ever exceed a specified value. Any of the above-mentioned plugins will do that reasonably well,  as long as your maximum amplitude is reasonable.
 
However, very few of them can guarantee no overs in every scenario. For example, if your material is hitting 0dB (or higher) on a regular basis and average peaks are only slightly below that, then it's unrealistic to expect any limiter to be "transparent". That'd be expecting a plugin to do your work for you.
 
Bottom line is don't sweat it. Use whatever strikes your fancy, and just don't push it. Don't set your brickwall to 0 dB and don't set your volume so high that the limiter is constantly engaged. Sounds like that's your plan already.
 

Boom! +1

Bit has a way of making the best point the clearest. I thought he was talking about inter sample peaks for some reason. LimiterN0.6 has that in the last module. I'm not sure how Loudmax or Concrete Limiter deals with that exactly.

 
It seems to me that it should be a fairly straightforward thing to detect just the peaks above a certain level and bring them down, much like if you did it by hand on a waveform (I often do).  This wouldn't affect the rest of the signal at all and all peaks would be guaranteed to be addressed.
 
I get the impression that compressors, and limiters, have a more blanket like operation in which everything is affected by the ratio, the louder stuff just more so.  Not what BbAltered is looking for.  I suppose if the signal is all peaks then yes, the overall sound would be affected.