Humidifiers
 

I have a 5TN and a 6EG, love them both...My wife has been complaining about the space the cases and gig bags have taken up. We have come up with an idea to install hooks on the wall and have my basses hanging from the wall, sorta like in a music store. My question is, if I go that route, will I need to get an air humidifier to keep moisture in the air, or are those bad for the wood. Also, living in NYC we have days of the year where the weather is below 10 degrees, and high as 90s. Will my bass exposed be damaging in the long run?

Hygrometer
 

First step would be to go to homedepot & pick you up a digital indoor hygrometer that will let you know what the humidity is in your place. If you have all your basses stored near eachother then thats where you should keep the hygrometer. 50% with 70 degree room temp is perfect for everything. Anything over 60% is to damp & anything under 40% is to dry. If you find the place is dry get you a cool mist humidifier to use but don't run it near your basses as the surround area tends to be to moist you just want to make sure the moist air is few bing the opposite side of the room where your basses are.

Typo
 

Reaching not "few bing"

Moist air
 

Oh also the right humidity is key for everything (even electronics, alot of computer manufactures assembling factories in dry locations even use them). 50% keeps everything nice & happy but there is a thin line between proper humidity & the air being so moist the it leaves condensation on things which turns to rust on things such as pickup magnets.

You're right, I forgot about rusting of the pickups. Then I would also have to make sure that room stays around 70 degrees at all time.

Sunlight & drafty windows
 

Unless its sub 40% & cold in there I wouldn't worry about it.

Comfort is the Key..
 

If I feel cold or warm or dry or humid, so does my bass. Keep your air healthy and comfortable for you and your family and the bass will be fine.

A 2-tank humidifier with thermostat set at 45% is fine. In the warmer months use a De-humidifer when it goes over 50%.

Empty it weekly at the least or when it is full. Leave the Humidifier on as well on Auto because it can get dry at anytime. Just keep the water in there fresh and if possible, pour a cap of lemon scented bleach in each tank to avoid mold or mildew. Check your filters often and buy the replacement filters in advance.

If you can find a unit that works both ways, try it. But maintain the water to stay clean as well as the filters. Blowing moldy water in the air will only make thinks worse for you and your family.

Once you get used to it, it's like watering the plants. Light maintenance.