A weight peak hold. Those numbers are good for the 2209. I've tested it with B&K reps side by side with a Pulse system and numbers were exactly the same shot for shot.

There is a Mil Spec for the meters themselves. The B&K 2209 meets the Spec that other meter used and many of the meters you see people posting numbers with don't meet the spec.

I'm no sound engineer but I know the Milspec calls for a 20ms rise time. All the current digital meters are 30ms except for the Pulse system. The Milspec calls for a certain sample rate also
and the current digital meters are less than half except for the Pulse. Thats probably why the Pulse is 50k and the other meters are 5k. The 2209 isn't made anymore so they are hard to find but they work well.

The 2209 is in spec and was A weighted. There were a couple shots noticeably louder than others. I think unburnt powder building up and then burning off was the cause. The digital meter is useless for gunshots with a 30ms rise time and insufficient sample rate. It doesn't matter what you think, most modern digital meters are no good for measuring gunshots. The Pulse system works but is pricey.

The snipers hide article really makes the LXT1 look worse than Phil's presentation.  

It appears from the hide article, like one round might yield similar results and another show the LXT1 coming way short.

I have a lot of personal experience with two Larsen-Davis meters: The 800B and the LxT1. My 800B has a rise time of 13 microseconds, has an analog detector, and digital post processing. The LxT1 is guaranteed to have a rise time of 30 microseconds or better, and the maximum with a digital detector is 28. Both have the correct 1/4" random incidence microphone for the meter. The 800B and B&K 2209 have pretty much the same peak detector (better than 20 microsecond rise time).

At Gemtech last year, we had a B&K demo with their pulse system, although the mic they used (1/4") had a rise time of 6-7 microseconds. Interesting results. The 800B, 2209, and LxT1 are self-contained handheld meters. The Pulse is bulkier.

Unweighted (which is probably the most correct method) showed that the 800B read 4 dB low compared to the pulse and the LxT1 read about 9 dB low. Compared to the 800B, the LxT1 read 5 dB low. This is to be expected based on rise times and the sharp slope of the firearm peak.

However, with C weighting, The 800B read 1 dB low compared to the pulse and the LxT1 read 1 dB low compared to the 800B. The explanation is fairly simple: The weighting networks degrade the meters to match the frequency response of the human ear, and they essentially cut off at a little over 25-30 kHz. Weighting networks, in essence, degrade the meters to around 30 microsecond rise time.

MIL-STD has traditionally specified a rise time of 20 or better, but permits either A or C weighting, which I believe to be ill advised when considering hearing damage risk. When one installs a suppressor on a barrel, the suppressed barrel has to still dissipate the same amount of energy as non-suppressed, but the suppressor reduces the pressure (through primarily volume expansion) and spreads out the time-exit curve through internal turbulence and momentary baffle trapping. The result is a broader, more spread out and lower intensity peak with a more gradual slope.

The B&K Pulse unit is very expensive with the microphones and accessories (around $25K). This includes expensive software and a laptop is necessary. Fully decked out, it is portable, but not nearly as compact as a hand-held meter. Both the LD 800B and the B&K 2209 are long out of production, and as they age, repair parts are becoming really scarce. LD keeps rapidly dwindling trade-ins as a source of replacement boards.

The LxT1 is current production, is handheld, and runs on a set of AA batteries.It has a lot of features that qualify it as a precision meter for environmental measurements, and it has the best of the currently available peak detectors in handheld instruments. While not absolutely perfect for our purposes, it is the best available in portability and price point (around $3,000).

As long as A- or C-weighting are specified or permitted, the LxT1 is the best bet as a substitute for the 800B or 2209 if you keep in mind that it will read one to two dB low. Nothing else in its price range or portability will do the job. There are a lot of industrial sound meters available that are tempting, but not all have a peak detector (not the same thing as an impulse detector), and those that do have a rise time greater than 50 microseconds (which gets you well into the error region).

Please remember as you find an 800B or 2209 on eBay, these meters are over 25-35 years old and may no longer meet their original specs or be repairable. And few come with the correct microphone; most will have a 1/2" mic that definitely will not be adequate for firearm sounds. And, of course, you will need a calibrator which will run a couple of hundred dollars.

This is not true. Since the sample rate is so low it produces a bad curve. I've seen cans that are notably louder to the human ear meter quieter with the LD.
There is an equipment spec for a reason.

Obviously the below comments are framed around comparing data from one place and time to another.  Not doing as Ray mentioned above- simply comparing two products on the same day with no concern for any other tested data comparison you may wish to contrast with the day's testing.

Reading the above posts and the article and looking at the curves, it seemed that your analysis that the LXT1 would be ~5 DB's low unweighted and ~1-1.5DB low C weighted could be accompanied by a generalization that 2-3.5 would probably be true of A weighting which would probably soften the case for the LXT1.    The A curve appeared to downsample ~2.5DB less of the higher frequency area that you mentioned the shorter peaks were measured in.  

I was under the impression A weighting was still the most often used weighting in suppressor testing.  I've seen arguments for unweighted (which causes a 5-10DB increase depending on the testing equipment), and I personally feel that C makes the most sense given that it is the OSHA weighting system the 140DB threshold was based on, but using the weighting systems as if they are interchangeable is obviously the best way to pollute the value of data in general.

My personal feeling was that unweighted results would confuse everyone who had been following testing, with A weighted data up to 20 years old framing their conceptual understanding of silencer performance.   To a lesser extent C weighting still represents a shift in the data.  

I get your point that it makes sense for an alternate and new field portable system to exist for the sake of the future of testing.  

It is interesting that sound engineers don't seem to care that the best current lab systems have 6ms peak rise and that 35-40 year old systems have ~13ms rise, and "state of the art" field portable units have ~28ms peak rise time.  We live in a world where there are a lot of impulse noises that are not firearms- machine components, jackhammers, stamping equipment etc being some examples.    It would seem obvious that it would make sense for true state of the art portable equipment to have the capability to at least halve the 28ms rise.  Even a reduction to 20 would suggest they cared about performance.  There are a lot of 30ms meters, so any improvement would be a stand out performance specification.