Hello. My control room is partially subterrainian and not always well ventilated on days when not in use. I keep all my microphones, outboard, cpu, tape machine in this room.
I have digital temp/humidity meter in this room. During the past winter, i was in the 30-45% range. Lately when I walk in the room, it has been noticably more dank, slightly musty. The humidity reading is around 60-64%. Is this level okay for my equipment? Especially my microphones. Or is this alright? Thank you, nico.

It's a lil high, i tried keep my levels at around 50%

Humidity as high as 60-64% for an extended period of time is not good for your gear especially electronics. Get a dehumidifier and run it when you're not in the studio...shoot for 45-50% humidity.

I went through a BIG problem with mold (that is the musty oder you're smelling) and long story short cost me $25Gs in mold remediation and 85% studio rebuild.

PM me if you want to talk more about it.

Needless to say mold and the high humidity that feeds it is nothing to take lightly.

Can you suggest a brand that offers a silent model?

I think Soleus Air make "whisper quiet" ones. I use the old noisy type but only run them when I'm not in the studio, usually overnight.

If I am shooting for 45-50% and am at 60%, is it a waste to buy a dehumidifier? Is there another solution? should i move my mics to another room?
What do i do about the possibility of mold? thanks again. nico

Indeed run one or more dehumidifiers. Keep several humidity gauges at various points in the studio and keep an eye on them. Make sure you have decent ventilation throughout the studio... in other words, circulate the dehumidifed air throughout. An extra fan or two here and there is good.

Forget trying to get a "quiet" dehumidifier... any decent dehumidifier that actually works will make more noise than will be tolerable in a studio... but, as s_sibs said, just run it at night... keep it on all the time, and turn it off when you are about to do audio work, etc.... that'll be fine.

Remember that an air conditioner IS a dehumidifer. So, for cases where you have a problem with both heat and humidity, start out by getting a good air conditioner and go from there.... watch your humidity gauges, you might be fine with just the AC only. A ductless split type AC is great for basements, etc. If the AC alone does not cut it, get an additional dehumidifier. Oh yeah, dehumidifers tend to heat the air... so if you already have a problem with heat, a dehumidifer will make it worse... so, for warm sitations, indeed start with an AC.

Also... be sure to insulate your space. If you have a room built within a basement, you should have a good vapor barrier in the walls to keep your dehumidifed air IN the studio and keep the damp musty humid air OUT. If you have no vapor barrier, your dehumidifer / air conditioner will run a lot more than it needs to, wasting electricity.

you know the deal with humidity and what it can do , heres something some dont know ...IT WILL RUST SOME METALS racks!!!!!!! and the humidity levels dont have to be as high as you may think for that to happen...we have a back room we stuck some old gear in ...888 16's rack fx etc etc ...went back there about a year later and we found paint bubbling and brown rust forming in on some of the gear and no there wasnt a leak on the gear...turns out someone had closed the dampers from our main hvac system send returns that went back there and walla rust, dont even get me started on mold ...read your gear specs for humidity info ....if you need a humidifier as well make sure you test the unit outside your control room preferably at home, we have tried a few units in some production suites that weve found to have left a white film on gear...not pretty and they were top end models...just some fyi from first hand experience

Rae

my studio has to many humidity too

now i know that around 50% is good

thanks

Over the past year I've found that in my basement, the temperature seems to be the same as the relative humidity almost all year long.... quite interesting. In other words, in the winter the temp is 50 degrees F and the RH is 50%... in the spring and fall the temp is around 65 degrees and RH 65%... and in the summer the temp is around 75 degrees and RH 75%... seems to track quite consistently all year long.

A problem I am finding now in the basement... if I run just an air conditioner, it does not get the RH low enough per temperature. I can run the AC to get the temp down to say 68 degrees F, but then the RH is still at say 62%... and I'd prefer it a little lower. I can lower the RH by running the AC harder, but then the room will get too cold and be uncomfortable. Looks like I may start using a dehumidifer along with the air conditioner.... keep the AC set to say 70 degrees and the dehumidifer set to say 50% RH. Of course the dehumidifier heats the air so in that regard it will be working against the AC, but... hopefully together both units will be able to keep BOTH the temp and RH where I'd like them.

Oh yeah... if I forgot to mention, basements suck.

Also in a basement.

Your aircon should de-humidify the air. At least ours does. But it is about the length of time it runs, not about the temperature.

Rod Gervais' book, "Build it like the pros", was very educational. Basically, most aircons are over-spec'd in relation to normal environments. Office for example are extremely inefficient when it comes to cooling, because windows are left open, doors are left open, and an enormous amount of the cooling is lost.

In a properly designed studio, the rooms should be air-tight. So from a cooling perspective, studios should be incredibly efficient. The problem is, if your aircon consultant over-spec'd your machine, then the machine only needs to run for 20 minutes to achieve the correct temprature. But the problem is that it takes longer than that for sufficient condensation to build. After reaching the correct temp, the aircon switches off. Now the condensation has built up, but not enough for it to drain away. So it just gets circulated back into the room. On top of this, an aircon's most inefficient period of operation is the first 10 minutes. So you pushing up your energy bill too.

Originally my aircon spec'd a 48,000 BTU machine. With the assistance of Rod Gervais' book and the downloadable tools, I realised i would only need 20,000 BTU for the CR, and 18,000 BTU for the tracking room, before fresh-air was taken into account. So i have ended up with a 24,000 BTU for the CR, and a 20,000 BTU for the tracking room.

There is a link in Rod's book to the downloadable files.

I think the problem with basements is rising damp and not actually humid air causing the problems with mold. Leaking underground pipes and inadequate ventilation underneath houses is a big issue for rising damp.

Condensation and lack of airflow is going to cause mold as well, cold windows and walls will condense any excess humidity in stagnant air. The best dehumidifiers heat the air a few degrees above the ambient temperature and keep it moving, then draw it back in to the condenser to maintain the RH.

Once mold has started to grow getting rid of it is very very difficult, sometimes depending on the type it can make you really sick too.

Eh, I have the exact opposite problem. We were tracking last winter and the guitarist's Strat was crackling like crazy. We swapped cords, opened it up and checked the jack, etc. Turned out to be static buildup.

I have to water my acoustic guitars and piano weekly. But having grown up in Michigan, I don't miss humidity. At all.

The good news is that my eight year-old car looks pristine. They use cinders here in the snow instead of salt, so cars stay cancer-free.

I left my bass in a friend's basement in Michigan for a month, years ago, and when I opened the case back up the leather strap had grown a nice green beard. Sweating profusely into that strap probably gave it a nice growth medium. Yuck.

My studio is in Michigan and I fight all elements in my studio. My studio is a converted barn and it is well insulated. I keep my RH @ 50% all year regardless of temp. My studio is roughly 800 sq/ft. I run both an AC and dehumidifier in the warmer months and a full house wick type dehumidifier in the winter. It's about 15 deg out right now and I'll burn through 3 gals of water a day keeping it at my desired setpoint. I have never had issues with rust, mold, mildew, condensation, cracking, swelling, oders etc....etc.... You shouldn't buy gear until you have everything you need to keep your space climate controlled.

Winter temps while not in use: 52 deg F
Summer temps while not in use: 78 deg F
While in use: 68 - 72 deg F depending on the time of year.
ALWAYS 50% RH and stays very constant.

I run a full size HEPA Filter air cleaner as well.

I think one thing people forget is that comfort is an important factor while being creative. Lighting & climate can have a direct effect on your final product.

Your levels aren't horrible, but like others have said, keeping it around 50% is good. Too much humidity is bad for mic capsules, as the moisture can form around the capsule.

I have the opposite issue where I live. Humidity in the winter is incredibly low, to the point where I have to use humidifiers. Trying to do a vocal session with 15-20% humidity = ☹☹☹

I run de-humidifiers in all my rooms when not in use. It's an easy fix to a problem that can have dire consequences!

Do it!

You guys are amazing and I'm most impressed with your knowledge.

I’m looking for an option to cool my very small closet/vocal booth (not ventilated) in my home studio in Los Angeles. I don't have central air but I do have a window A/C in the bedroom…but it's too noisy, and also not feasible to run a duct into the closet.

I’m looking at building one of those DIY ice chest A/C units, and I'm wondering if the ice chest A/C generates any condensation that might damage electronics and/or condenser microphones. The general setup of the A/C is a small fan blowing air into an ice chest full of frozen water bottles, then the cold air comes out through a PVC pipe. I would have the ice chest right outside the door with PVC pipe going through the wall into the booth. 

In the booth, I have two condenser mics, a guitar amp, an LED monitor, and bluetooth keyboard and mouse in plastic bottles?

More importantly, if there is condensation from the ice chest A/C, does that lead to a possible mold situation? Or could it also lead to rust on some metals? A dehumidifier seems like a good option, as suggested here. Or am I just overthinking this? Thanks...I'm a newbie here. Tom