starting equiment that ic cold from being shipped

Hello,

I would open them up and put the components upside down if you are worried about condensation. If it does form and drip it will be at the top of the components where there are no electronics. I would leave them that way for 24 hours to be safe. Once they get acclimated to the room you can set them up and put in standby. This will slowly warm things up. After a few hours turn it on and leave it on for 24 hours to finish charging up the caps. After all that you should be good. Some of these components can take 200-500 hours. So you will definitely be drying it out. I hope this helps. 

Some funny responses. I once blew up an older TV with a picture tube turning it on when I had just taken it out of my garage in winter. It arced, smoked & made some horrible noises in its dying moment. Picture didn’t actually implode which might have been worth the whole thing - it was a old piece of junk. 
 

Now I know better & if I something is cold, I remove from it’s box or boxes & let it sit at room temp for at least 3-4 hours which should do it. Like others mentioned,  Condensation is the cause. 

There is no such thing as a “sealed” amp. At best, a top panel might have a bit of foam to damp it a tad from vibration. Otherwise, any moisture will be present. It certainly isn’t necessary to open anything up, and I highly doubt the conversion of moisture would result in a dripping amp. But as mentioned, it’s just a smart thing to do to wait. This is assuming the amp was below say 40° or so. Much warmer and it is doubtful it would be an issue. Sub freezing? Without doubt let it warm up for a couple of hours. No worries.

@feldmen4 Thanks for the gentlemanly apology Matt, but I took no (zero) offence.
And your expertise in the field is seeming more helpful than not..

@bossa

"My frost knee jerk..." I guess auto correct is warning me to wait
…

I was thinking condensation, so it is either auto-correct…
or
Maybe I pictured it being so cold that the condensation frosted up like a very cold drink?

If it was an auto-correct, then it must be the latest release of the auto-correct s/w, as it got it exactly right.

@bossa Early in my career I did thermal analysis - modeling problems just like this. I can tell you that it depends on the thermal properties of the materials the amp is made of. More or less the denser the longer it will take to come to equilibrium (room temperature). My 24 hour comment was flippant and was just reflecting your initial post. OMG that’s an awesome pair of components- just looked them up. The FPB is massive - and as you say “ long awaited”.  I would suggest 3-4 days but that is purely a conservative SWAG (scientific wild ass guess). I think this situation calls for being conservative - what is 4 more days after all the time you’ve waited just to get it right?

Regarding open box or not. All air contains water vapor. How much water vapor is in interior air depends on ambient conditions (outdoor temperature and humidity) unless the air is conditioned or humidified. For where @bossa lives humidifying air is common in the winter which would provide more available water vapor in the interior air. Even if they don’t humidify there will be much more water vapor in the air in the room than in the box. That means much more H2O that could wind up as condensation on the various cold surfaces of your components than is in the box. I have never received even a cheap electronic component that isn’t factory packed in a plastic bag with some sort of desiccant packed inside the plastic bag. That plastic bag + desiccant will keep your component nice and dry as long as the bag is sealed. Once you open it the desiccant cannot work quickly enough to protect your components and condensation will likely form.  As I mentioned in my first post if water vapor inside the box was an issue the condensation would have already formed during shipping as your components cooled. I guarantee you do not want to open the box during the warm up period. 
 

@agentwja - what you experience with double pain windows does not mean the water vapor in the house has been reduced. Rather that water vapor can no longer reach the cold inside surface of the glass windows here it would condense (just like on the cold surfaces of @bossa components). The cold inside surface is only exposed to a sealed area that is filled typically with argon gas to reduce re-radiation but it is also dry so there is no moisture ( water vapor) to condense on that surface (the inside surface of the outer pane of glass). The inside surface of the second pain which is exposed to the water vapor in the room is not cold enough for condensation to form - rather it is close to room temperature because of the excellent engineering of these windows.