Thiel Owners

Regarding concrete repair - look for expansive grout at Lowes, etc.

I am confused about expansive grout. everything that I've read says its purpose is to open cracks. can you elaborate in a little further?

Hello
I have been a long time reader and fan of this forum. I have Thiel cs7 that have been upgraded to the 7.2 to say that I cheated on the audiophile path would be an under statement. i bought my speakers from a fellow audiogoner appx. 5 years ago, at that time I thought my Krell ksa 100 amp would suffice, but everything I read said 7.2s NEED power and plenty of it. So I started researching and listening to bigger amps. i was just about to pull the trigger on some Mac 501s when I read about the Thiel liquidation auction in Tn. I now have the Krell fpb 600c that Jim used to power his/my speakers.
When I bought the speakers the concrete baffles were cracked but everything sounded great. Now with the bigger krell on the speakers I am getting air through the cracks which causes distortion in the woofer of my left speaker.
I talked to Rob a few years ago about the cracks and he said there was a small shop near Thiel in Ky. that use to do those repairs but they closed about the same time Thiel closed. 
My big question is "has anyone repaired a cracked concrete baffle or know someone that can repair a concrete baffle"?

Tom I am a precision millwright with over 30 yrs of experience we normally use epoxy grout for our motor and pump bases. The millwright trade has changed a lot over the last 10-15 yrs we no longer pour our own grout. We usually set a piece of equipment on elevation and maybe do an alignment, but the "civil crew" will do the grouting.
I like the concrete caulk idea. I've tried 2 types of concrete sealers on the cracks. I used duct tape on the bottom to contain flow but the sealer would always leak. I am going to try a new sealer from the job with the concrete caulk.
 I will take pics and keep you posted.