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
Thank you all for the excellent responses. I first need to clarify a bit more which will address much of your input. What I didn't expect was quite this degree of info. so let me add to my original post.
*The entire project was built with one ever-present mindset during the entire process: In order to keep the sound from getting out (I did not want anyone knowing music was playing inside) I was going to build the entire room like a fishtank....one with absolutely no leaks whatsoever, and this is exactly what I did.
* The detached garage was built in approximately 1946 using what appears to be a very solid 3/4" hardwood (don't know the type but it IS a HARD wood...) mounted onto 2"x4"@ 24" on center studs with diagonal cross-bracing between each stud. The roof is also this 3/4" wood. It all sits on some type of poured cement foundation. 10 years ago it was vinyl sided (as was the house) and I had a new roof put on when I began the re-modeling which included the removal of the previous roof tiles, repair/replacement of any questionable original wood, then the addition of fresh tar-paper and new roof shingles.
*Original interior LxWxH was 19'x13'5"x9'with the 9' @ center of a peaked roof, (sidewalls @7').
*The 4" studs are what forced me to use the R-13 @3.5" thick as compared to an R-19 or R-30 which were 6" thick,(it was actually R-16 I believe, as I'll explain in a minute).
* Wall insulation was a type of recycled cotton denim, it was either "Ultratouch" or a similar competing brand (can't remember at the moment) touted for its ease of use, all natural fibers, and superior noise suppression characteristics.I believe it was actually rated an R-16..,
* Acoustic Sciences Corp. "Wall Damp" strips were applied to each stud before 1/2" QuietRock 510 was screwed to them.
*The same ASC "Wall Damp" material was then applied onto the Quietrock ( called "Wall Damp Squares")before the standard 5/8" sheetrock was attached next, thus providing a thin "air barrier" between drywall sheets. This was done to both opposing 'long walls' (the 19's).A type of special "Quiet Seal" caulking was used around the entire perimeter of both walls, plus additional extra tubes of silicone caulking "For good measure" to ensure no sound leaks...
* The short walls (13') were done more extensively because I felt I could spare a little room length.. The aft wall had R-13 between studs, followed by 2 layers of 1/4" particle-board(I had a whole bunch of it laying around so I pressed it into the insulation and bent nails on both sides to hold it in place). Followed by 5/8" sheetrock. I then found a few rolls of tar paper and completely covered it with that. THEN I framed out a new 2"x4"@24" on center based interior wall which I screwed another layer of 5/8" sheetrock to on the OUTSIDE of it (What a job that was getting it all screwed together and raised up). Once that was up it was another application of regular Owens Corning R-13 insulation. Final interior sheetrock was another layer of 5/8" sheetrock. This makes for a total # of layers from the outside inward as: Vinyl Siding, 3/4" [original]outside wood, R-13, 1/2" of particle boards, 5/8" drywall, tarpaper, a 1/2" air-gap, 5/8" drywall, R-13, 5/8" drywall.
* The front garage door wall was replaced with a new garage door (insulated) and bolted into place. A 5/8" sheetrock was screwed to its inside face. 1/2" air-gap and a new interior 2"x4' @24" on center framed-out wall with[again] a layer of 5/8" sheetrock screwed to its OUTSIDE facing side. O.C. R-13 between studs. 2 layers of 1/4" each particle board (same as the other end), another 5/8" sheetrock, a layer of "Quiet Glue" (a competing product to the famous "Green Glue"), and then an interior layer of 1/2" "Quiet Rock 510" as the interior wall.
I guess the "weak link" in all this is the roof @ only R-13, covered by regular 5/8" drywall on 3/4" firring strips,but when I go outside with the music on LOUD... it certainly can't be heard if some of it is actually going up...
Wpines: if the winter really gets brutal and my 2 oil filled space heaters really can't keep up, those heating units might be a great choice as a retrofit. Thanks for the tip.
Hifitime: I'm not ready to run a gas line out just yet, but in the big picture if winters become consistently raw, it's also worth a look. I'm on Long Island and the proximity to the ocean keeps temps here a bit more moderated than inland so it's usually not as bad as other areas of the state.
Blindjim, thanks for all the thought... you're right that extremes should obviously be avoided and fortunately I don't think it will ever get too extreme... if the interior ever gets much less than 50 or so I'll be out there with both heaters getting it back to at least 60 (one unit can pretty much do that alone). Besides, it is nice not to wear a jacket while listening of course (I haven't had to yet). I have no concerns about power outages or restarts either...as I have paid A LOT of attention to the dedicated power I'm running out to it (but that would be another post).
Jea48: I'm sure you're right... oh well. Do you think the textured finish I added to the ceiling paint thickened things up a tiny bit to help??!?
Elwood: thanks for the thorough evaluation. I do have a hygrometer in my room [in addition to the thermometer] for monitoring humidity. It has been at the dry end of the normal zone (about 40%) ever since I first powered everything up (late October) and it is something I will absolutely be monitoring at all times, especially summer. I will resort to a window based A/C unit which I'll "pre-cool" the room with while equipment initially warms up (I usually give it all a solid 1/2 hr before listening), then take occasional listening breaks as needed to turn it back on for re-cooling... I don't need the noise of it during listening and I have 2 ceiling fans which are quiet enough for actual listening.
Peter_s: I don't think it really takes too much juice to heat it up from the low 50's to the low 60's with the portables... Maybe it really does?? I'll find out when my winter electric bills start coming in... uh-oh?? And you're right: if I do get another 'real' heating system, quiet IS a MUST.
Tpreaves: HVAC system was certainly in my mind during construction. I figured one of those wall mounted ductless systems could always be added later if absolutely necessary once I've been through a full year of hot and cold weather. I hate to admit that $$$ was a deciding factor in this department... a decent ductless unit with both heating and A/C would run between $1500-2500 and I thought the window A/C unit and a couple of space heaters was worth a shot for something like $300 total... Also, a dehumidifier if needed (though the A/C unit helps)I'll know by this time next year if I played it right or not.Thanks.
Magfan: Window is double pane, plus I bought some lexan from my local H.D. and cut it to fit the window. I added silicone around the edges and pre-drilled then screwed it to the perimeter of the window as an extra layer. Inside, just below the glass, I built a full width "Ledge", 5/8" deep, with matching window trim which I use to support 2 sheets of 3/8" drywall that are 'Quiet glued' and screwed together, then trimmed with a thin layer of O.C. insulation (against the actual window trim) then secured on top with a latch to keep it snug against the window area. This provides more soundproofing and a certain degree of insulation as well. (There are vertical blinds in between too). Only problem is I'll have to build another one for the summer with the window A/C unit cut out for it.Temps can see high 80's to low 90'sF in the summers here at times.
This was all very helpful and a big thanks to everyone. Any other input is always welcome and I promise never to make another post this long. Happy Lissn'n
When not in use, laying some thick bath towles over the tube gear should help avoid condensation issues. 20-30 min after listening just lay them over the gear. I do it to prevent or try to prevent dust accumulation inside the equipment.

Humidity is key... if you are very comfortable in there, can't see your own breath when exhaling, not needing heaters, sweaters, drinks, AC or fans, the gear should be comfortable enough too.

Do look at those tubes surfaces though, from time to time before start up... just to get an idea.

Good luck.
When not in use, laying some thick bath towles over the tube gear should help avoid condensation issues. 20-30 min after listening just lay them over the gear.
12-14-09: Blindjim
Not sure that would be a good idea. It may actually do more harm than good. I would think it would be best to let the hot then warming air, as the equipment cools down, to rise and dissipate in the cooler air of the room.

Food for thought.... late 1950s and earlier car radios used tubes.
Jim
Lissnr
It sounds like you did put a lot of effort and hard labor in your garage.I understand what hard work is because I finished all the interior of my three floor home by myself.
Judging by your description and if my understanding is correct,I would of done things a litle different ,for example I could add a 2x6 on the side of every existing stud (sister studs)to allow R21 insulation installation,then 6mil poly for vapor barrier,plus 5/8 fire rated gypsum board or double it up.A more expensive alternative would be spray foam on all cavities by a company that specializes in that.
Regards
George
Thanks again guys, The towel idea is interesting...I'll think about it but honestly...unless I'm away for more than a day (not likely upcoming) I'll be out there every day/night cranking the heater back up from never less (hopefully) than 50, up to 60+, all the time. Even with a fairly cold spell a few days ago, I have yet to see it go below 50. Trust me, I WILL be monitoring it always. My main question was really just a better ballpark of how cold could it get before I should really be concerned (assuming I WASN't watching it).
Yioryos: Thanks for the kind words... the 2"x6" were the first thing that crossed my mind and an excellent idea but I immediately decided against it due to the reduced width the room would have... I was convinced that my speakers (and most speakers in general) prefer a reasonably wide room, as much as, if not more than length and I just felt that extra 4+" was something I didn't want to sacrifice. Right choice or wrong...who can say... but I'm pretty pleased so far with the results.
Thanks again everyone.