Cold room, Bad for equipment?


I'm a very fortunate guy in as much as I've recently finished transforming a gutted detached garage into my dedicated listening room.After 1.5 years and hundreds of personal man- hours I am putting the finishing acoustic panel touches and tweaks and finally enjoying the music. It is extremely well insulated with R-13 insulation between the studs and a layer of both 5/8" drywall over 1/2" quiet rock all around, except for the ceiling which is only 1 layer of 5/8" and the R-13. Floor is carpet over laminate over Dri-core, so that's not a problem either but I live in NY and due to the added complexity of an HVAC system, I have not added any heat to the room.With winter temps dropping to less than freezing I'm wondering what is considered a minimum temp I should try to be maintaining through the use of portable space heaters in order not to be harmful to my equipment. This includes a mix of some units in stand-by mode (my tubed pre-amp with low voltages keeping them warm) as well as CD transport, Dac, and self-powered sub woofer which are always left on. Amps are left off of course, both a big solid state Classe monster as well as a tube amp.My in-room thermometer has read as low as 50 F tonight and the space heater brought it up to 60... Obviously the amps will warm things up a bit while playing but the big question is how low can I let that temp go without doing any possible harm to anything???Note there is 1 30"x60" window with blinds and a 3/8" piece of sheetrock pressed up against it (from the inside), effectively sealing it closed. The one door is a standard"outside" door with a separate glass storm door outside of it. The original 'car' garage door has been sealed and a new internal framed wall (sheetrocked as the others) is in its place. Thanks in advance.
lissnr
Hello Jea48: Yes,you understand correctly...the vaulted ceiling is the bottom of the 2"x4" roof rafters and there were 2"x4"x approx 13' or so ties (I call them cross beams) tieing the outside long walls along the eves to each other... just before I began the project I had a good friend of mine who is a GC come in and assess the structure. He declared it quite sound except that he noticed a slight bowing along the centerline of the roof ( you really had to look hard to notice it)... so what we did was take a heavy duty floor jack and a big 4"x4" x 8'ish and at the midpoint we gently raised it back up to level while a few of his workers took 3 big 2"x6"s and installed them in place of the old ones. They were nailed and then through-bolted (w/ 5/8" bolts) to really keep it all well locked in nice and tight again. I removed 4 of the original 5 which were redundant/not doing much/if anything and the roof is good and secure again. With roofers all over it after that it was completely fine and I'm sure any snow accumulation shouldn't be a problem. Obviously to maintain ceiling height I simply painted these exposed beams the same ceiling color ("Chalk white" from Ben Moore) and they look pretty great.
I'll be updating my system pics soon, and show the new room... the one there on my "system link" now is my last room(in an apt.). I appreciate your obvious insights into the "big picture" of all the fine details . Thanks again.
Just another follow-up. It was 25F last night/this morning and only 35 all day. I've been putting the heater on for a few hours each afternoon and it's never been lower than 50 when I walk in (before I turn it on). After heating it rises to low-mid 60's, then repeats this cycle pretty much every day/night. So, a 10-15 degree swing in that range and I think I should be OK for the winter season.[I'll keep track if it really drops to the teens or single digits, but so far, so good]. Thanks for all the input, everyone... and happy Lissn'n. I'll be posting new pics asap, and I'll mention it. Best regards.
Please continue to watch out for condensation.
This is the #1 enemy of fine electronics under your conditions. People exhale lots of moisture and it will 'migrate' to cold places.

If you are where the weather is bad/major snow, you guys are getting creamed.
It's funny but I have indeed seen the effects of condensation on the window of my exterior storm door windows... as they tend to "cloud up" when I open/close the main outside door... otherwise I am pretty pleased with the hygrometer's reading of low humidity...Temps are remaining above 50F and therefore I'm hoping are OK for overall equipment usage. Please correct me if I'm wrong. Thanks
Sorry, I don't know the limits, but feel strongly that humidity and low, condensing temps are a bad mix with fine electronics.

I grew up in the midwest and winter was static electricity season. I think we also had a humidifier since there was little natural humidity in cold weather. It was also a pretty large, 3000ft/sq house of 2 floors. My ma used to keep a kettle on the stove and would turn it on periodically.

Did you wrap your new construction with Tyvek?