[not sure why but my post seems to have disappeared, trying again – ]
Thanks for the reply, Richard, I appreciate it. Very familiar with Sarah Jeffery, btw, I love her channel.
I have many years (alas) experience with wooden acoustic instruments (full grand piano in living room, custom acoustic guitars, mandolins, etc.), so I do have some familiarity with humidification and heat issues. Not that I’m an expert, certainly not. So yeah, as temperature rises, the air is capable of holding more water, so the RH goes down. Which means, heat up the area where a wooden instrument is kept, and it can start to dry out. Definitely.
The room where I keep my “stuff” is humidified (I use a Levoit humidifier with digital settings). I try to keep it around 40-45rh, although it can be a challenge in mid-winter (now) (New York). The temp in the room is usually around 70F during the day, down to maybe 60 overnight. Humidifier comes on and off “as needed”, but none of this is perfect.
As fars as I can figure, using a hot water bottle (and maybe a towel) does not apply any different kind of heat than heating the ambient air? It is still “dry heat”; the water in the bottle doesn’t leach out. 🙂 So if it’s hot enough to cause drying, it’s the same. Am I wrong? Maybe the real difference is, it’s localized and very short-term?
Anyway, I went ahead and tried this – I attached a 12″x8″ adjustable terrarium heater to the underside of the drawer. I put in three digital thermometer/hygrometers, and three digital Govee sensor units, all calibrated (salt method), spread around inside. Two of the sensors I put in (empty) recorder rolls. The Govees are great (I have a bunch of them), they read temp and RH on a standard phone via the Govee app. I’ve now monitored it for a couple of days.
Initially the temps ran way up, too high in my view (upper 70’s). I had to dial the heater all the way down to its lowest point to get the temps into the low- to mid-70’s. At this point, the drawer stays around 72F, even overnight (the Govee setup shows historical data, so I can see the highs and lows, both temp and RH). The RH stays about the same as in the room generally. I may add a couple of Boveda packs to the drawer, although I’m not sure it’s necessary.
So far, I think this is a pretty good setup. The recorders are not “cold” when I take them out. They still need some warming (under arm), but not as much. The whole recorder is kept at the same temp (and RH), slightly above room temp. Not “hot”, and not (imho) warm enough to cause problematic drying.
I was gonna post a pic, but I don’t see how I can get it down to the size limit. Anyway, any further thoughts on all this would sure be welcome!