Extech 407730 Digital Sound Level Meter 40-130dB

I got this a few days ago and its an incredible meter. first, it uses the much cheaper AAA batteries vs the expensive 9 volt batteries. I have a callibrator and it measured right on when I got it. the instruction manual doesnt tell how to calibrate it but the online manuael at extech does show you how. this meter is a very accurate CLASS 2 meter, a CLASS 1 is better but costs $700+ dollars. this meter can be used in court procedings and government monitering. a UNCLASSIFIED meter that costs under $100 or so is not nearly as accurate as a class 1 or class 2. ( class 1 & 2 is slightly better meters than TYPE 1 and 2 meters). this meter does A and C weighting, peak measurments, and max and minimum measurements over time. the ONLY thing I dont like? its only backlit for 10 seconds after pushing the button. for $126 for a class 2 meter from a top company like extech its the best sound level meter you will find. spend the $126 on this meter plus a $110-$150 for a class 1 calibrator like I bought on amazon and you will be set for years of accurate sound level measurements. dont bother with the $20-$80 meters if you want true readings.

I picked up one of these to help level match my subwoofer to my main stereo system. It has A and C weighting, and I used C as recommended. It worked great for this without needing to understand anything, right out of the box. I also used it to see if the level on the noise machine in my nursery was in the safe range, and adjusted it a little. There's a lot of buttons I probably won't use, honestly, but this is well made. It comes with a wind foam shield which you can use for outside applications. For quick estimates of sound volume (for unofficial purposes, I'm not sure how well calibrated this is) or for comparing two sources to see if they are the same, this is the right tool.I also used this to point out to my wife that the home theater stereo wasn't too loud to do hearing damage. I then pointed out that her yelling at me at how loud the stereo was actually WAS loud enough to do hearing damage (90db!) and that she should probably volume down. Yeah, that didn't go over so well. I don't recommend using this for spouse volume testing. But for stereo equipment matching, oh yeah, it rocks for that.

This meter is very easy to se and a great size for use on a job site.

I have an older DB meter that does straight readings. I was looking for something that I could use for averaging and finding peak volumes so I gave this a try. It's not at all expensive, is easy to use, and seems to work correctly. I have a high end calibrated source for my older meter, and when I tried it on the Extech it read exactly the correct value. So in a static situation the meter is very accurate. While I don't have any way to test it for peak or average readings, I'm guessing that it's probably pretty darn close. I plan on using this for measuring shop machine noise levels, and also for monitoring sound levels for the PA for a jazz band I play in. If you need a DB meter, this one will do a good job at a great price.

I have had to send two of these back for the same reason. When I returned the first one, the company said it must have been a defective unit, but the replacement one does the same thing.The problem is that the MIN/MAX function does not work properly. Even when recording very steady sine wave acoustic signals well within the device's measurement range, the unit often reports that the MAX signal value encountered during the recording period was too LO to be recorded. And about as often, that the MIN signal level encountered was too HI to be recorded. This obviously makes no sense, and points to a problem with the device's data acquisition or a software bug.If you just want to look at the numbers flickering by and make a guess about maximum, minimum, and average values over a time period, this might work for you, but for any serious quantitative engineering or scientific work, forget it. It's a hobbyist level tool at best, not a professional tool.