If you export a mono file from Sonar a a mono file, it will be boosted by 6 dB. If it was close to 0, there will be destructive clipping as a result. I destroyed an entire sample library I'd created when I "backed up" the files to three different media and then deleted the originals. When I brought the exported files back in to Sonar, they were all clipped because of the 6 dB boost. 
 
If this is what happened to you, the solution when exporting is always to export as stereo. If you must export as mono, reduce the gain by 6 dB before exporting.

6 dB really? I always thought it is only 3 dB!
It seems that I have understood something wrong! I have to check this!
 
Regards
Marc

Fireberd,
 
I noticed the same thing, Studio One 3 just sounds better. I am not sure about cakewalk by BL I heard the Audio Engine sounds better now in cakewalk. Alas I have not downloaded it so I wouldn't know but going from SPLAT it has it's own sound. Which is noticeable. 

dappa1
Fireberd,
 
I noticed the same thing, Studio One 3 just sounds better. I am not sure about cakewalk by BL I heard the Audio Engine sounds better now in cakewalk. Alas I have not downloaded it so I wouldn't know but going from SPLAT it has it's own sound. Which is noticeable. 

Does Studio ONe 3 sound better than SPLAT?

Under summing conditions only I would say no.  In fact  olakunleodebode  started a thread saying the opposite. SPLAT sounded better!  You are both wrong in my opinion.  But once you start using internal stock plug-ins and things then all bets are off.  Anything goes.
 
When Studio One exports a mono file there is no change in level from what I can see.  Same with stereo file too.  Also fireberd would not have engaged the console shaper either.  You have to consciously make that decision.  It is not something that you can stumble on accidentally that easily.  The stock console shaper is only basic too in its operation. (CTC-1 is much nicer but a separate purchase)
 
One thing I found out too is that Studio One actually records 3 db lower than what the meters say as well.  I think they do it to introduce some headroom. e.g. if you see a clip light during recording chances you did not clip at all.

I've exported single (mono) tracks before - many times - and never noticed a signal gain.  Sometimes I'll export a track so I can do some editing in Goldwave and then reimport it to Sonar.  I don't see any signal gain, it remains the same. 
 
In this Studio One example, all the tracks (8 tracks) were exported from Sonar as mono tracks and imported into Studio One.  All the tracks except the one Bass Drum track were at 0db and didn't really sound any different.  But because of the gain increase I noticed a (positive) difference in the sound of the Bass Drum track.  How that happened is the "64 dollar question".   I later also exported a Bass Drum track from an older session and it too was OK (0db).  
 
Sonar/CbB is still my production DAW.  Studio One 3 Pro is still a "learning experience".  I've got several upcoming (paid client) recording sessions booked and they will all be done with Sonar.
 

If you export a stereo clip as mono, then I can understand. From my experience I've always had to reduce gain on stereo clips when converting to mono within Sonar, so exporting may be similar. I can only guess this is because the conversion is combining the volume of the two channels into one channel.
 
Kind of like taking two glasses, each half full of water, and combining them to make one glass. Now one glass is at full volume while the other is empty.

soens
If you export a stereo clip as mono, then I can understand. From my experience I've always had to reduce gain on stereo clips when converting to mono within Sonar, so exporting may be similar. I can only guess this is because the conversion is combining the volume of the two channels into one channel.
 
Kind of like taking two glasses, each half full of water, and combining them to make one glass. Now one glass is at full volume while the other is empty.

iirc, the amount of gain change during conversion is affected by your pan law settings?

In my case the tracks were mono and I exported as mono.  No stereo involved.