politics
Welcome to the discussion of US Politics!
Rules:
- Post only links to articles. Title must fairly describe link contents. If your title differs from the site’s, it should only be to add context or be more descriptive. Do not post entire articles in the body or in the comments.
Links must be to the original source, not an aggregator like Google Amp, MSN, or Yahoo.
Example:
- Articles must be relevant to US politics and contain quality and original content. Social Media adjacent hosts like Substack are allowed, but ONLY if they tie back to a company/subsidiary. No personal or friend group blogs and no self-promotion. Articles should be worth reading. Clickbait, stub articles, and re-hosted or stolen content are not allowed. Check your source for Reliability and Bias here.
- Be civil, No violations of TOS. It’s OK to say the subject of an article is behaving like a (pejorative, pejorative). It’s NOT OK to say another USER is (pejorative). Strong language is fine, just not directed at other members. Engage in good-faith and with respect! This includes accusing other users of being bots or paid actors.
- No memes, trolling, misinformation, or low-effort posts/comments (including reposts). If you see posts like this that anger you, do not engage. Report, block, and live a happier life than they do. Any slap-fight is subject to comment removals. Fights full of rule violations will result in temporary bans to cool off.
- No manipulating votes via bots or alt accounts; this will result in permanent bans. Vote based on comment quality, not agreement. This community aims to foster discussion; please reward people for putting effort into articulating their viewpoint, even if you disagree with it.
- No hate speech, slurs, celebrating death, advocating violence, or abusive language. This will result in an account ban. Usernames containing racist, or inappropriate slurs will be permanently banned.
We ask that the users report any comment or post that violate the rules and use critical thinking when reading, posting, and commenting. Users that repeatedly have comments or posts removed, weaponize reports, or violate the code of conduct, will be banned.
All posts and comments will be reviewed on a case-by-case basis. This means that some content that violates the rules may be allowed, while other content that does not violate the rules may be removed. The moderators retain the right to remove any content and ban users. The reason(s) behind moderator action(s) are publicly available through the Modlog.
That's all the rules!
Civic Links
• Congressional Awards Program
• Library of Congress Legislative Resources
• U.S. House of Representatives
Partnered Communities:
• News
view the rest of the comments
Sound cannons are actually pretty weird, in that they don't work like you'd imagine them to work. They produce sound when multiple beams of ultrasound collide with an object, so if they're pointed at you, you're the one producing the sound that hurts you. That's why they're so effective.
Some people online have done some tests, and thin cardboard appears to be the best way to stop them. Put the thin cardboard before you, and it stops most of the sound. It can be the cardboard from a poster, if you have one.
Ear protection headphones (for workshops) also help, and their effectiveness is enhanced further by wearing small earplugs inside. Active noise cancelling headphones don't help and can even be counter productive, so don't use those.
To be a little more pedantic, they send ultrasound frequencies and they "degrade" into regular audible sound waves when they collide with something (combination of harmonic effects and destructive / constructive interference). The reason they send ultrasound instead of using regular directional speakers is because it's smaller wavelength is easier to aim so much more of the energy moves forwards, so you don't hear much noise coming from the source itself.
That's why they work for "crowd control". A strong enough regular speaker would bother the operator too much.
The noise cancelling part was particularly fascinating. Not only was it ineffective, it amplified the sound. I think its because noise cancelling circuitry relies on the ability to create a signal frequency that cancels out the initial waveform. That's all well and good, but I think the sound cannons use separate speakers out of phase. Since the noise cancelling headphones produce a signal in phase with the first frequency detected, the microsecond slight delay causes it to be added to a subsequent phase boosting the power.
4