What are the most suitable hygrometers that you fellow flute players use and recommend?
Hygrometers are basically a choice between cheap and un-calibrated vs. the more expensive calibrated ones. The one I’ve been using lately in the cheap category is a ThermoPro TP55:
It sits on the shelf of a bookcase in my practice room. What I like about it is the very large display. I can see the numbers from halfway across the room. I should also own a calibrated hygrometer but they’re expensive. I could find out exactly how accurate this cheap one is with a sling hygrometer, and I’ve just never gotten around to it.
I live in the Pacific Northwest USA where the climate is fairly mild. We don’t run the house heat enough to drive the indoor humidity below 30-35% except during brief Winter cold snaps, where I run room humidifiers just to be safe. Right now in mid December it’s running between 42-47% rh in the practice room. It’s a big drafty house that tends to “self regulate” unless the heat is on full-time. If I lived in a very dry climate, or one with deeper winters, I’d be a little more strict about hygrometer accuracy. In my current situation, a cheap hygrometer that might be a few percentage points off is probably good enough.
I believe it was Dave Copley who sent me, long ago, a simple circular hygrometer that I’ve
used ever since. I far as I can tell, it’s very accurate. I’ve dropped it and cracked the glass face several years ago, and the device is still very accurate.
Jim, I believe you, but how do you know it’s accurate if you have nothing to compare it to? Years ago a friend of mine bought five Radio Shack hygrometers (they were cheap) and as an experiment he set them all up in the same location and they all gave different readings. Not wildly different, but different by a few percentage points. When we’re talking moisture levels for flutes I don’t think precision is important and even a hygrometer that’s off by 5-10% is still useful. But if it’s off by more than 10-15 percent you may be over- or under-humidifying. The only way to know would be to check the meter’s reading against an independently calibrated hygrometer, and most of us don’t have access to those!
I figure “in the ballpark” is good enough and I actually use one of those Radio Shack hygrometers, running on two AAA batteries that run the thing for several years.
I don’t positively know the cheapie is accurate, but I believe it is and, I think, for good reason.
I’ve used it for 17 years without cracks, etc, and in places where humidity got very low. I run
a humidifier through the winter and check it against the hygrometer. There was one exception.
Casey pointed out once that wood really starts moving around at 35 percent humidity,
and the one time I had a flute crack (a lined headjoint) was when I foolishly let the humidity
(according to the hygrometer) descend to 35. Sure there is room for skeptical scenarios and doubts,
but practically speaking my belief is sensible.
I used to buy those hygrometers in bulk from a cigar supplies place and include one with every wooden flute. I would calibrate them against the Oregon Scientific hygrometer that I use in the workshop. The cheap dial hygrometers are easy to disassemble and then you can rotate the cardboard dial relative to the mechanism. Of course they would only be “calibrated” at the particular relative humidity that you chose to perform this operation. I would try to do it at around 50% RH. A spot of superglue would then fix the dial in place so hopefully the calibration would not shift if someone dropped the hygrometer. Lately I’ve been buying small digital ones. They can’t be calibrated but they mostly read within 5% of my shop unit and I throw out the ones that don’t.
This is interesting. My estimate of the accuracy of my particular hygrometer is probably correct, but it’s due to a guardian angel correcting defects in the original lot. So my positive opinion of the accuracy of cheapie hygrometers in general is doubtful, as Dave is a local phenomenon. One for the journals, I reckon.
From what is posted above it seems the hygrometer sits in the room. Is that preferable to being in the flute case?
I notice that my fiddle playing friends who use hygrometers have theirs in their fiddle cases.
Depends on how you are humidifying at home. I use a humidfier that humidifies the whole room, myself included. These are reliable, reasonably priced, durable and they work, and you can see when they are empty. One filling lasts maybe eight hours or more. If that’s how you go, the hygrometer stays on the desk or wherever it is in easy reach or is plainly visible.
That depends on whether you are humidifying the room, the case or a box that the case sits in.
I keep flutes (in their cases) in a Tupperware-type container that contains a damp sponge in a plastic soap dish with holes drilled in the top. In the driest part of winter, I also put a pill box with holes and containing a small piece of sponge in the flute case. In the latter situation, I have a hygrometer in the Tupperware container and another in the flute case.
I don’t really care whether the hygrometer is accurate to 2% or 5% but I do count on it to give me a general sense of the humidity and, perhaps more importantly, an indication of major changes.
Them’s my thoughts.
Best wishes.
Steve
The way I see it, a hygrometer small enough to fit in a case might be good for extended travel, like staying in hotel rooms. Although I wouldn’t trust the cheap little analog dial hygrometers that are sometimes built into guitar or fiddle cases. Get a decent small digital one if you’re going that way.
Larger hygrometers designed to sit on a table or attach to the wall are likely to be more accurate, or at least easier to read, like the big one I linked above. My S.O. and I have other instruments in the practice room like mandolin, guitar, and her fiddles. So for us, it makes sense to use a hygrometer that reads the room conditions, and a room humidifier when needed during cold snaps.
Personally, I’m not a fan of trying to maintain humidity inside closed cases at home, unless you just can’t control the room well enough. It’s easy to over-humidify, for one thing. I leave my flute cases cracked open so they can adjust to the room, and all the other wooden instruments are out on stands. YMMV, sometimes humidifying in a case is the only option for more extreme conditions.
To put my situation in context - the climate here in the south-west is typically more damp than in eastern England. What concerns me is the dry air caused by winter heating and I’d like to have some measurement of that effect to avoid any potential problem. We heat our home with a combination of gas central heating and wood fires.
Personally, I’m not a fan of trying to maintain humidity inside closed cases at home, unless you just can’t control the room well enough.
I can agree that in a tupperware box, it might be possible to over-hydrate, or at least maintain the humidity so high that the flute inside doesn’t quite dry out, or heaven forbid, you get mold.
In my climate, it would be difficult to humidify the whole house or even a room during the Winter, but it is easy to keep a higher-humidity box.
I’ve monitored my home humidity over the past couple of years here in Colorado, definitely a dry part of the US. The interesting thing is that the humidity sits between 40 & 60% for most of the year, aside from the the Winter months when I can see humidity around as low as 15-20%. I have no air-conditioning, but I do have central heating.
The surprising thing to me was that my house humidity stays in a moderate range during our very dry Summers. I believe this is because I use a whole-house fan, which brings in cool night air. Cool air is much more humid that hot air - natural cool air, not air-conditioning, which extracts a lot of moisture.
I went with this one: https://www.amazon.co.uk/d/Weather-Thermometers/ThermoPro-Digital-Thermo-Hygrometer-Thermometer-Temperature/B01H1R0K68/ref=sr_1_5?ie=UTF8&qid=1545159924&sr=8-5&keywords=hygrometer
The current humidity reading in the room where I keep my flutes is 52%. Actually higher than I expected.
When it comes to humidifying a flute, these are the bees knees (Model #1): https://humistat.com/
They also offer basic analog hygrometers.
I just ordered my first non delrin flute…and I am getting a bit frightened, reading this thread and realising, how important and difficult it can be to control humidity for your instrument…uhh
Important? Yes. Difficult? No. Hard to choose? I get it.
It only seems esoteric because of people having so many pet ways to go about it. Some humidify special rooms, autoclave-style. Some just humidify the case. Some pay close attention to hygrometer readings. Some just do whatever works and simply keep the moisture delivery system from drying out. Some use costly, professional-grade systems. Some just make their own; for example, many a guitarist has taken a plastic travel soap case, perforated it all over and tossed a sponge inside it. The important thing is that you do it however you do it, and above all take flutes in humidified cases out for a run every day: they’ll need the airing, otherwise mildew can set in.
That’s about it.
If your flute case comes with something like one of these (a humidor humidifier):
…it won’t be enough on its own in a very dry climate. For flutes I’ve used guitar and violin humidifier worms:

…one for each section, and cut to size; one end has a clip and I just toss that but keep its cap for later. The violin worm is for the foot section due to its smaller diameter, but I’d use the larger guitar worms for the rest. One end cap has a flange that should be trimmed away, but along with trimming the inner sponge to accommodate re-capping, that’s about as much fiddling as it takes. You just soak them, squeeze out the excess, and make sure the exterior’s dried off before you insert them into the flute parts. Generally they should be replaced every year. Others will prefer different approaches, but it was quite satisfactory for me. Some foot joints have too narrow an inner diameter to accommodate even a violin worm’s smaller size, though, so it’s not a universal option.
I humidify my apartment, too. I’m able to keep it at around 40% - 50% rh, so that’s good, but with rings still falling off anyway, it was evident that the instruments needed a little extra all the same.
It’s not really that difficult to control humidity. It might cost 'ya, depending on how far you want to go, but the methods aren’t that difficult.
At the top end, you can get a whole-house humidifier for your HVAC unit if you need it. A major step down in expense is a room-size humidifiers, which aren’t very expensive ($50-$150 USD) and just a PITA to keep refilling with water. Get a “cold mist” unit if you go that way. Or you can use a plastic tub with a tight lid, with a damp sponge or cloth inside to store your flute case. Or you may live somewhere like South Florida where it’s not something you even have to think about if you’re running the AC almost all year and it’s holding 60% humidity.
I’m a fan of the room humidifier because I can just leave my flute out in the practice room, or in the case with the lid cracked. And in my climate, there are only a few months of the year when I even have to do that.
The first step is to invest in one of the more inexpensive (but still reasonably reliable) digital hygrometers like the ones mentioned earlier in the thread. You need to know what your current and worst conditions are, before tackling methods to humidify. It’s possible to go too far and over-humidify, even to the point of encouraging the growth of nasty mold, if you aren’t able to assess what needs to be done. Or if anything needs to be done at all!