Top positive review
100 people found this helpful
They work and they're inexpensive
on January 26, 2011
I bought one of these to put in my classical guitar case. My nephew just bought an $1800 Martin guitar and he also bought one. We each have different brands of hygrometers but they both read RH of 39% to 41% inside the cases. My house has 2 small room humidifiers going all the time in the winter which keeps the air somewhere around 30%. His apartment is dry as a bone with no humidification at all.He probably gets down to 20% when it's really cold out and he has the heat cranked up. Yet the humidity in our guitar cases is the same.
The reviewer who said they don't absorb water at all is wrong. I weighed the Herco on an electronic gram scale when I bought it. Dry, it weighed around 75 grams. After soaking it for 5 minutes in a bowl of water, it weighed 80-85 grams. Then I zeroed out an empty bowl and started adding drops of water. It turns out the Herco absorbs about a teaspoon or two of water. Not much, but all you need to keep the guitar in a safe range. After all, all those people that advocate putting a sponge in a plastic container with holes drilled into it always tell you to wring it out. After you wring it out, how much water do you think is left. I'd guess around a teaspoon. It just doesn't take that much to humidify such a small space. The humidifier that came with my humidor for tobacco measures about 3x8x6 inches. The humidity goes to 68%.That humidifier also only holds a teaspoon or so.
Bottom line, it's dangerous to put a humidifier inside the guitar. Much better to use a Herco. I resoak mine about every 2 weeks. When I first got it I'd check the weight of it, knowing that if it went back to 75 grams, it was dry. After checking that a few times I came up with the 2 week time span.
The absolute perfect humidity for a wooden musical instrument is somewhere between 40 to 50%. The Herco keeps it in the lower range of that here in wintry New England.