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FREE recalibration special for our customers, just send us your meter and 15 U.S. Dollars for return U.S.A. shipping

We also calibrate

Sound Level Meters, Microphones and Spectrum Analyzers, email for a price quote

Unlike some companies, whose calibration is unknown or unreported our sound level meters, and our system calibration proudly meets or exceeds, and is traceable to:

N.I.S.T.: National Institute of Science and Technology

U.S.A. Military, MIL-STD-45662A

ISO 9001

ISO 9002


ISO/I.E.C. 10012-1, 17025


ANSI/NCSL Z540-1, Z40

ANSI S1.4-1983 TYPE S1

ANSI S1.4-1984

ANSI S1.43-199X TYPE 1

ANSI S1.12, Type M



United States of America: Bureau of Standards, F.T.C.

United States of America: F.A.A.

Boeing Aircraft (6-82479)

European Union: Bureau of Standards

PBT: Physikalisch Technische Bundesanstalt

NAMAS: National Measurement Accreditation Services

Instrument Society of America

BNM: Bureau Nationale Metrologie


BS5750 PART 1

The American National Standards Institute

I.E.C. 651 Type 1

I.E.C. 804 Type 1

I.E.C. 60942 1998 CLASS 1

I.E.C. 61094-1 and 2

...and over 150 Countries Worldwide!

Futhermore we calibrate with REAL SOUND, not some electrostatic or electronic comparison calibrator like most of the "world class" microphone sensor companies do...and not just one time but TWICE, on different days to further increase accuracy to 0.05db!

Each microphone is individually hand calibrated with 3 independent computers and 4 independent precision electronic systems with actual high pressure sound waves, with cross reciprocity electronic amplification and source generator calibration. This is so each microphone gets a very accurate, independent calibration chart, and

Below, is a sample calibration sheet supplied with each 186 db microphone sensor or RTA microphone, note the extremely flat linearity from 10 to 700 hertz, actually from 2 (two) hertz. All the new sensors have built in automatic temperature compensation for even more accuracy no matter what the weather. The image is in low resolution for people with slow internet

Why is calibration so important anyway? Sound Decibel Level is real and it's either:


170.75 db = 1 pound per square inch

air SPEED of

146.1 db = 1 meter per second

air POWER at

1 Watt per square meter = 120.05 db

With this info you can calculate the excursion amplitude(very real when looking at a speaker moving), frequency, acceleration, compression, Watts, Volts, Amperes ect. (all real measurements).

Decibels and pressure is real (and a real number) like your weight. If a very small child told you the cat they were holding weighed 450 pounds, would you believe them?

I hope not.

But what if this child took out a scale and then put the cat on it and it did read 450 pounds, would you believe the child then?

I hope not.

Logic and common sense would convince you that there was something wrong with the scale. It's either broken or mis-calibrated. If you go to a store to buy 160 ounces of chocolate, the scale should read 160.0, not 154.3, not 161.4 just 160.0 ounces. This should be true everywhere in the world. Hopefully every scale is very close to 160.0 ounces or maybe 159.4 or 161.2 ounces. Would you buy food off a scale that always reads high? I wouldn't because your never getting what your paying for! Your grocer is telling you you have 160.0 ounces and you are paying him for that, but on every other scale in the world it reads 151.2 ounces.

If we wanted to we could make a meter that says you got 2000 db, but it would be FANTASY. You would be getting cheated. Don't get cheated, Don't cheat yourself, know your calibration.

In general we agree with the calibration of: AudioControl(3050A,3055 to 160db only),Bruel and Kjaer,(ONLY up to 140 db or the microphone rating , or their hydrophone mic.and at only above 100 hertz), LinearX (to 157db), Omega, Endevco, Kistler, PCB and the new Tern Pro/Lab db drag,

Just an example of 10 happy worldwide customer examples say decibel levels;

1:162.7term 161.9our

2:147.1 term 146.7 our

3:153.4 our 153.3 term

4.156.6 our 156.6 term

5.148.4 our 148.4 term

6."138.4 our 138.3 term"

7."Great Product!! Only 0.2db off of my term lab"

8."Mic cal is real close to a termlab, works fine"

9."Shipping was quick, unit works great. Tested against a known SPL source A+"

10."Thanks a ton for a price affective alternative for a 1500.00 meter! Quick shipping"

11."Completely awesome meter, finest on the planet, thanks a bunch!"

Furthermore, all our microphones have their calibration level clearly marked on them for anyone to read, no hidden computer files; key codes, calibration factors, or frequency weighting systems. All OUR microphones are completely interchangeable with any other of OUR microphones;computers, digital multimeters ANYWHERE IN THE WORLD and they will all read the same db level!

We are very aware of the other car stereo competition microphones, and most read to high. As an example some read +3 db at 130db, +4 at 140db, +5 at 150db, +6.5 at 165db...ect. If you want to lie or impress yourself I guess that would be great, but it is not a scientifically useful number. For your benefit we also include a substitute formula to get the car stereo db organization numbers. We love car stereos as much as anyone, we just want to bring back common sense, and less "ARBITRARY" rules.

Most car stereo competitions have only one sound meter, and allow only one "sound meter", and only one "judge" and only one "inspection" team so CHEATING is notoriously common. If cheating wasn't happening they would let anyone use any sound level meter they like... (just try it, and they will tell you: "NO, you can't use YOUR meter!"). They don't want anyone to cross compare to PROVE the actual db level (or at least agree that vehicle A is louder than vehicle B).

If those companies or organizations had nothing to hide, why don't they show their CALIBRATION? We do, and so do many other N.A.S.A. grade sound companies (whose meters are extremely expensive).