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Dank
02-15-2007, 10:54 AM
Please help me in my search for the most accurate hygrometer. My guitars hang on the walls of my basement studio all year round. I have good units for humidifying the guitars during the winter, so that is not an issue. My problem is trying to mearure the amount of humidity. I do my best to maintain the RH at 45 to 50%. I use one Radio Shack Hydrometer and two from Oregon Scientific. I have tried calibrating the Radio Shack model per the instuctions provided by a fellow forum member. I cannot get the hygrometer to read 75% in a plactic bag with salt. Consequently, I fear that my readings are inaccurate.

Therefore: who has experience with an extremely accurate hygrometer? I will spare no expense to properly humidify my guitars. All advice is certainly appreciated. Thank you for your time.

Dan

Herb Hunter
02-15-2007, 01:59 PM
Here are some I am considering as a replacement for my 4 Radio Shack/Oregon Scientific units.

http://www.bkprecision.com/www/np_specs.asp?m=625

http://testproducts.com/safecart/product_info.php/cPath/93/products_id/525

http://testproducts.com/safecart/product_info.php/cPath/93/products_id/207?osCsid=a3fd1ff92e17cf6a763ae49acb08d298

http://www.2dihydrometer.com/hygrometer.html

woodruff
02-15-2007, 02:31 PM
currently i am using the planet waves hygrometer, though i dont like their soundhole humidifiers, their hygrometer is great and from what i can tell, accurate. turns out my previous analogue hygro was way off. i just leave it on a shelf in the room where my guitars are kept in their cases. it was around 30 bucks i think, maybe a bit more.

at the same time, "most accurate hygromter" is an oxymoron, much like jumbo shrimp or easy financing. still, yu should be able to get a reasonable accuracy using the planet waves hygro.

bluesman67
02-15-2007, 03:25 PM
A $25 Oasis from http://elderly.com/accessories/items/OGH2.htm. According to them, they've tested it against their analog hygrometers and it is accurate. I've been using it for the past 3 months and my guitar definitely has been kept in the preferred RH zone. It's been sounding great w/ no signs of whatsover of dryness. The heat has been on a lot where I live and the house is definitely very dry, but I use this to measure the RH in my guitar case and it's been good for me.

freestyle
02-15-2007, 06:22 PM
The capfull of salt in a baggie with your hygrometer will give you the plus or minus that your hygrometer is off. That's all you need to know to be accurate with your readings. The salt is always 75%. If your hygrometer reads 82%, then its reading +7. Simply subtract 7 from your hygrometers reading to get the actual humidity. It's really that simple. Good luck!

Dank
02-15-2007, 08:35 PM
Thanks for the recommendations, guys. I'm currently doing the baggie/salt calibration to see if my hygrometers pass the test. If not, I'll look into other units recommended here. Thanks again.
Dan

Dank
02-15-2007, 08:44 PM
Herb: I looked at your suggestions. I don't mind paying more, given what I have at stake, but do you have any personal knowledge about these products other than finding them thru Google?

JoeInLex
02-15-2007, 09:02 PM
For what its worth, I have tried:

Radio Shack 63-1032 - Accuracy good, price good, size too large for case

Radio Shack 63-1089 - Crap

Humicase Compact Hygrometer - Small, as accurate as the Radio Shack with about +/- %5 accuracy (yet typically reads right with the Radio Shack model); works great in my guitar cases (I have a humidifier in the guitar room but still have in case humidifiers (Planet Waves) as the result of shutting down the main humdifier during the day when I'm at the office)

Planet Waves Instrument Hygrometer - A little less reliable than the Humicase and somewhat bigger so less convenient for in-case use

Cheapo Kroger GE Thermometer / Hygrometer - Got exactly what I paid for -> crap

John Pearse K-Saire Humidifying System - about the nicest hygrometer. Trust it more than other short of the next one

Fluke 5020 - About the best darn unit you can find. Quite overkill mind you, but in my line of work, I have access to one and I can borrow it.

Generally speaking, I think you'll be hard pressed to get a hygrometer for under $100 that does much better than 5% accuracy. Also, most of these same units do much better at higher humidity than at reading lower levels so your accuracy will be less as you reach lower numbers. So if you calibrate on at the 75% mark and find your difference, unless you stay near 75% RH, your values displayed can be way off as you get to the lower humidities. Don't know this as a fact for all manufacturers just know this from testing some of the above units against the Fluke (I'm an engineer and I was bored).

Good luck.....

OscarTehGrouch
02-15-2007, 09:14 PM
The capfull of salt in a baggie with your hygrometer will give you the plus or minus that your hygrometer is off. That's all you need to know to be accurate with your readings. The salt is always 75%. If your hygrometer reads 82%, then its reading +7. Simply subtract 7 from your hygrometers reading to get the actual humidity. It's really that simple. Good luck!

From what I recall this isn't true... if you are off by 7% on the salt test... that means your thing reads 7% over... you just dont simply add or subtract (it's relative)

At any reading, that would be 107% of the actual humidity level... in any case... the difference should be negligible

Please correct me if I'm wrong...

gteague
02-15-2007, 10:32 PM
<Del>

Fluke 5020 - About the best darn unit you can find. Quite overkill mind you, but in my line of work, I have access to one and I can borrow it.

<DeL>


ever see those tv reporters broadcasting live under some palm tree in florida during a hurricane holding up an ipod-sized device with a wind sensor on it?

9 out of 10 times those are the kestrel weather meters. the one i have is here:

http://www.kestrelmeters.com/Kestrel-4000-Weather-Meter.pro?sNav=0

but this is the cheapest one i could find on their site that measure s humidity:

http://www.kestrelmeters.com/Kestrel-3000-Wind-Meter.pro

i know there would not be many willing to spend that much, but there is a chance some on here would wager $129 against a $2-3k guitar. much like joeinlex with the fluke, i had this as a result of my ham radio tornado tracking days and didn't buy one especially for monitoring humidity for instruments, but it's very handy to compare my other hygrometers against. a very nice feature of the one i have is a min/max/logging memory so that i can spot trends and spikes.

/guy

Dank
02-16-2007, 07:19 AM
Generally speaking, I think you'll be hard pressed to get a hygrometer for under $100 that does much better than 5% accuracy. Also, most of these same units do much better at higher humidity than at reading lower levels so your accuracy will be less as you reach lower numbers. So if you calibrate on at the 75% mark and find your difference, unless you stay near 75% RH, your values displayed can be way off as you get to the lower humidities. Don't know this as a fact for all manufacturers just know this from testing some of the above units against the Fluke

You've hit the nail on the head. I strive for 45% to 50% RH, obviously far below the 75% benchmark. That could explain the inaacurate readings, correct? That being said, isn't there a good alternative to the Fluke 5020 which sells for $1,585.00?!

Herb Hunter
02-16-2007, 07:27 AM
Herb: I looked at your suggestions. I don't mind paying more, given what I have at stake, but do you have any personal knowledge about these products other than finding them thru Google?

Last year, at the Nashville airport, a climatologist from NOAA struck up a conversation with me asking about my Taylor. (He had an old Gibson and had heard a lot about Taylor.) I mentioned the inconsistency of the hygrometers I had and asked him if he could recommend one that was less than the $300. He said he thought the B&K Model 625 was a good field unit, the one in the first link I provided. The other links are for units I found for comparison purposes.

Dank
02-16-2007, 07:33 AM
Thanks, Herb. I am going to contact a few of these maufacturers and speak with them . The price of the unit that you recommended is reasonable.

wedge199
02-16-2007, 07:47 AM
German made with a good calibration booklet.
http://www.12fret.com/retail/accessories_pg.html

Dank
02-16-2007, 07:51 AM
Ooohhh, I like that Hygrometer from 12th Fret. Very simple and elegant. Too many choices, now. ****!

woodruff
02-16-2007, 07:52 AM
For what its worth, I have tried:

Planet Waves Instrument Hygrometer - A little less reliable than the Humicase and somewhat bigger so less convenient for in-case use


Good luck.....

like, how unreliable. i am using this one now to measure RH% in my bedroom(where guits are kept in their cases). it reads pretty accurate. but perhaps i should test it soon.

Dank
02-16-2007, 08:01 AM
I've narrowed my search to the B & K, Kestrel Metrics and the Barigo, sold by 12th Fret. I am going to speak with each manufacturer and see what they have to say about accuracy and the ease of calibration. I'll report back (for those who have an interest ;) ).

woodruff
02-16-2007, 08:06 AM
Ooohhh, I like that Hygrometer from 12th Fret. Very simple and elegant. Too many choices, now. ****!

that is cool! but they should have a red bar above 60% too.

JoeInLex
02-16-2007, 10:22 AM
like, how unreliable. i am using this one now to measure RH% in my bedroom(where guits are kept in their cases). it reads pretty accurate. but perhaps i should test it soon.


Probably not the answer you would want, but the honest one........ Accuracy varies among the several that I have. One of the reasons why I have purchased other hygrometers was because of the inconsistency (these guys almost always can be worked into a guitar purchase as a freebie). If you are wondering why I have so many, I tend to be overly cautious with stuff and I travel with at least one guitar all of the time. When I'm away, my wife does me the favor of maintaining the family. I just feel more comfortable having a generally accurate room unit and getting a good feel for how each case protects my investments.

Zorker
12-14-2011, 11:38 AM
Any new hygrometer devices worth considering?

Thanks!

cjd-player
12-14-2011, 11:54 AM
The most accurate hygrometer is a sling psychrometer.
http://www.ambientweather.com/mafaredspslp.html

You can check the accuracy of digital and other units with the salt bag test. But use potassium carbonate rather than table salt.
http://www.soapgoods.com/Potassium-Carbonate-p-719.html

The potassium carbonate gives a slat bag test reading of 43% relative humidity, which is more relevant to guitars than table salt and 75% RH. Also eliminates any discussion about whether corrections are linear over a wide RH range.

Buy 1 pound for about $10 (with shipping) and it will be enough to test your hygrometer every winter for several years.

peteom
12-14-2011, 12:05 PM
The most accurate hygrometer is a sling psychrometer.


The average relative humidity error using the sling psychrometer is +9%

http://www.tqc.eu/rsrc/artikel_downloads/rh_dewpoint_electronic_meter_vs_sling_psychrometer .pdf

Howard Klepper
12-14-2011, 01:07 PM
The best are analog mechanical units made in Germany. So far as I can tell, all the popular digital brands come out of one or two factories in China and use the same sensors. IMO people's experience of accuracy with any of these brands is a matter of random chance.

The Abbeon sold by LMI is a very good one. Many consider this unit to be the standard for quality. LMI's price is as good as anyone's on it. About $165. They come up used regularly on Ebay.

The Taylor 5565 can be found discounted for about $60, and is also made in Germany. They don't guarantee the same degree of accuracy as the Abbeon (5% v. 3%). I see that it got a couple of negative reviews on Amazon, FWIW.

[edit] This site has the Taylor 5565 for $60. http://www.partshelf.com/taylor5565.html

Tanque Verde
12-14-2011, 01:29 PM
I live in the Sonoran Desert and earlier this year, when I first took up guitar, I went on an insane hygrometer goose chase.

I bought a high-end West German Analog Abbeon Certified Hygrometer on Ebay, a twenty dollar cigar-industry digital Akar hygrometer, and an eight dollar Taylor hygrometer at ACE. I also dug out of the closet the hygrometer that came for free with a humidifier I purchased years ago.

I calibrated all of these using the salt test and then re-calibrated them with a cigar-industry calibration kit. (As if to confirm the vanity of human endeavors, the free plastic hygrometer required the least calibration.)

Since my goal is to keep my guitars between 45-55% RH, I came to the following conclusion. Instead of a single lab-quality instrument, which for all its precision still at the end of the day cannot provide ultimate peace of mind without corroboration, I personally am content with two or three inexpensive hygrometers (the cigar industry specializes in these) that all cluster in the immediate vicinity of 50% after adjusting for error.

It's nice to have more than one hygrometer, as well, because you can compare the RH of your house with that of your cabinet or case. After an unusually intense winter rainfall yesterday, the RH in my house has topped 70%. But my cabinet has risen only to 53%.

steamfurnace
12-14-2011, 03:20 PM
Interesting discussion so far. I have a whole house humidifier mounted on my furnace heating duct, and currently it is set at 45%. Yesterday, the outside temperature averaged 35 -40 degrees, and the furnace thermostat is set at 70. My cheapo hygrometer that I also received free with an old, now gone, console humdifier read 40% in our study. The analog weather station in the family room read 50%, and a similiar weather station on the basement wall read 58%. I just received 4 analog cigar hygrometers I bought on Amazon for $1 each, and all 4 of them read 42%. I'm going to take an average, and say I'm ok:)

ljguitar
12-14-2011, 03:45 PM
Interesting discussion so far. I have a whole house humidifier mounted on my furnace heating duct, and currently it is set at 45%. Yesterday, the outside temperature averaged 35 -40 degrees, and the furnace thermostat is set at 70. My cheapo hygrometer that I also received free with an old, now gone, console humdifier read 40% in our study. The analog weather station in the family room read 50%, and a similiar weather station on the basement wall read 58%. I just received 4 analog cigar hygrometers I bought on Amazon for $1 each, and all 4 of them read 42%. I'm going to take an average, and say I'm ok:)
HI sf...
I know from moving the same hygrometer around the house during the day that different rooms do exhibit different levels of relative humidity, and it's not always the hygrometer's fault that it gives different readings.

A unit in my kitchen will read a full 5 points less than one in my play room (which I keep humidified). And even in homes with furnace assisted humidifiers read differently in different rooms.

I agree that cheap hygrometers will allow us to keep the humidity well enough that we can keep our guitars at safe levels, and know when to move them to the case rather than leaving it out in a room.

steamfurnace
12-15-2011, 09:09 AM
Hey Larry,
Despite my post, I do take keeping my guitars humidified seriously. I have Planetwave soundhole humidifiers in all of my solid wood acoustics, and check the sponges weekly. I was amazed at how the action on one of my guitars changed last winter, when I neglected to monitor it's humidifier; and the guitar was in the case. Once I re-humidified it, the guitar and I were both much happier making music together.

ljguitar
12-15-2011, 09:16 AM
Hey Larry,
Despite my post, I do take keeping my guitars humidified seriously. I have Planetwave soundhole humidifiers in all of my solid wood acoustics, and check the sponges weekly. I was amazed at how the action on one of my guitars changed last winter, when I neglected to monitor it's humidifier; and the guitar was in the case. Once I re-humidified it, the guitar and I were both much happier making music together.
Hi sf...
I didn't think otherwise.

I'm agreeing that even inexpensive hygrometers will help us monitor our instruments well enough to keep them humidified properly and hold the levels stable.

And a stable humidity level is better than just safe levels. It keeps the action you spoke of more consistent.

Judson
12-15-2011, 09:56 AM
currently i am using the planet waves hygrometer, though i dont like their soundhole humidifiers, their hygrometer is great and from what i can tell, accurate. turns out my previous analogue hygro was way off. i just leave it on a shelf in the room where my guitars are kept in their cases. it was around 30 bucks i think, maybe a bit more.

at the same time, "most accurate hygromter" is an oxymoron, much like jumbo shrimp or easy financing. still, yu should be able to get a reasonable accuracy using the planet waves hygro.

Wal-Mart has one under the brand name AcuRite that only costs $8 ... it gives the current humidity and temperature as well as the high and low for each over the pat 24 hours.

kerbie
12-15-2011, 10:25 AM
Dank,

I tried 3 of the cheap little hygrometers with no success at all. I don't think they could have read humidity if I had dunked them in a tub of water. I finally decided on a pretty nice model built by Honeywell and have been extremely happy with it. It cost me more money than the $10 models, but I realized that company had been building hygrometers into their heating/AC systems for years and maybe I could benefit from their expertise. In my comparisons, it is deadly accurate.