Upcoming reviews:

[silencertalk]

We will do MP5 cans next because there is the least of those. Then 5.56mm and 9mm pistols.

Everyone -- my last testing generated over 1 GB of data. Very time consuming to compile it. It might take 3 weeks for all of the backed-up data to be published.

Yes I could just dump raw numbers sooner, but I need to do prepare the photos, charts, weights, measurements, and description.

[Debo18]

Thanks Rob, take your time. After all I am going on 5 months for a Form 4 so how much could 3 weeks hurt! Keep up the good work.

[dtarbox]

looking forward to the results.

[Tugnut]

me too

[silencertalk]

So I had the 'rise time' of my recording electronics tested and it was 20 microseconds. The mil-std calls for '20 microsecond or faster rise time.' I also learned that my 24/96 Khz converter is not able to process sounds greater than 20Khz even at 96Khz sampling. This is just the kind of scam a consumer needs protection from. I already ordered new gear with 40Khz bandwidth. We will see improved testing in the future.

[dtarbox]

I also learned that my 24/96 Khz converter is not able to process sounds greater than 20Khz even at 96Khz sampling.

What net effect will this have on the data.

[m2hb]

Great job on your work.

Any interest in recording data on sound level vs. # rounds fired (e.g., at the start, after 100 rds, after 500 rds, after 1000 rds,...)? Muzzle flash tests? Muzzle velocity?

[William Perkins]

Robert, my memory of high school music class is that humans can't hear above 20KHz. Are you getting a 'better' microphone because it will reflect how humans perceive the sound or is it also more accurate within the range of human hearing? Is there a reason why you would want to meter sounds outside of the range of human hearing (worried about the guard dogs reacting to the shot? ) My concern is that a suppressor that does not suppress well in the ultrasonic spectrum might 'meter' worse (because the microphone can hear what we can't) even though it sounds better to a human.

Anything that can't be improved upon...will soon be obsolete.

[silencertalk]

I am getting a better mic because mine clipped on an an M4 at 1 meter. I had to take the unsuppressed reading at 2 meters and then add 6 dB to it. Since people question the validity of stuff like that, I will have to spend what it takes to get a metel-diaphram mic. They say I am 'calculating' the results rather than 'measuring' the results.

[William Perkins]

I also learned that my 24/96 Khz converter is not able to process sounds greater than 20Khz even at 96Khz sampling. . . . I already ordered new gear with 40Khz bandwidth.

Posted: I am getting a better mic because mine clipped on an an M4 at 1 meter.

I DON:T have a thorough understanding of this but it seems like two different issues. Yes? No? I don't even know how to ask an intelligent question but I'll try anyway.
1) Is the clipping that occurred to the unsuppressed shot at 1 meter related to the sampling rate (96Khz)?
2) Is the 'better' microphone going to hear further into the ultrasonic spectrum?

You can't build a reputation on what you are going to do.
Henry Ford

[silencertalk]

The mic was clipping because it could not handle the SPL and was not related to the 20Khz bandwidth of the A/D. The A/D however was measured at having a 20 microsecond rise-time, which is bordering on too slow, which can cause other problems. The 40Khz bandwidth A/D should have an 8-12 micrsecond rise-time which will be nice.

The new mic should not overload and will respond more quickly.

[PCArms]

We will do MP5 cans next because there is the least of those. Then 5.56mm and 9mm pistols.

Will you include an SD in the MP5 tests?

Also, I thought I read you were using an attenuator to drop peaks down to a usable level? Or am I mistaken?

You are doing an AMAZING Job, thank you sooo much for your efforts!

[silencertalk]

Thanks.

The attenuator was not to reduce SPLs. It was to keep the mic signal in range of the mic input.

The SD was included for reference -- not to be 'scored' against the others.