Stupid Thunderbeast

[Aloha_Shooter]

Who is the guy at the end of September that got paper approval in just 4 days? Whose flipper did he have to rub??

Probably a personal friend of Obama or Holder, maybe Al Sharpton or Michael Moore? Oh wait, they're against the public having these dangerous items so they can't have any paper in their names; it would be the bodyguards they hired ...

[Dave]

I've been looking at their ultra-5 and ultra-7 for an AK SBR project. The barrel is 11", so I'm trying to decide if the extra noise reduction is worth the extra length.

[Great-Kazoo]

I've been looking at their ultra-5 and ultra-7 for an AK SBR project. The barrel is 11", so I'm trying to decide if the extra noise reduction is worth the extra length.

Not really.. When you consider the AK's gas system not to mention that bolt carrier noise, you'll be better off with their original unit and length.

[Alpha2]

"bolt carrier noise"...are you referring to the "traps on a CVN" type of bolt carrier noise?

[Great-Kazoo]

"bolt carrier noise"...are you referring to the "traps on a CVN" type of bolt carrier noise?

I got out before CVN's. I was on a CVA.

[Duman]

I've been looking at their ultra-5 and ultra-7 for an AK SBR project. The barrel is 11", so I'm trying to decide if the extra noise reduction is worth the extra length.

Get one of each. 8-D

[Duman]

Heard today the new Ultra's won't be available until June.

[Great-Kazoo]

Heard today the new Ultra's won't be available until June.

That puts them out to Dec for actual delivery / approval.

[Dave]

That puts them out to Dec for actual delivery / approval.

Ouch. Maybe I should look at the thread about making your own can again....

[Tim K]

The dB math can be deceiving. A 3dB reduction is a 50% reduction, but can be difficult to detect that level of change with your ears.

If you have two noise sources, one at 135dB and one at 132dB, it would be very difficult to distinguish between the two, without instrumentation.

Correct. I got to thinking about this again and did some research from the audio industry about perceived loudness levels.

A 3 db change is barely perceptible
A 5 db change is clearly perceptible
A 10 db change seems about twice as loud

I also went back an re-read Zak's descriptions. The claim is 4-5 db quieter across the line. The first time I looked, I read it as the 7" can being 4-5 db quieter than the old 9" can. I think that's wrong. I think the new 7" can will be 4-5 db quieter than the old 7" can. Further reading leads me to believe the new 7" will sound about the same as the old 9".

It's a real, noticeable, and measurable improvement, but it's not what I initially thought. I still want one...