Just a quick observation:

I'm wondering about the rather dramatic disparity between a number of the weapons under "Weapon Noise". Living right next to a military base, a lot of these numbers seem... off. The Autogun and bolter (a rapid fire, rocket-propelled, shaped charge launcher) seem like they should be closer together. The lasgun seems to make a rather mighty crack to be audible at a full kilometer.

For comparison, the Earthshaker round and thunder (usually audible to 20 km) seems to be the only number that makes a lot of sense on this chart.

Even the knife impact seems a bit extreme at 20 meters (roughly 66 feet). What is this person throwing the knife into? Is the sound of a warhammer supposed to include the shocked cries of passersby as grimdark acts of violence happen?

Yea, the warhammer is a bit high, and the bolter should be closer (or even higher) than the autogun. Even if the bolt never reaches supersonic speeds (which is possible, that's one of the uses of gyrojets), and so the primary detonation to fire the bolt out of the barrel may be less loud than that of an autogun firing, the secondary explosion either immediately before impact or just after impact, an explosion strong enough to either fragment the bolt, further accelerate a dart of superheavy metal or create a shaped charge effect, should be heard from very far away. Without getting into the details of the reactive speed of the explosives used in the secondary charge, the explosion should be strong enough to be heard from at least the distance that a supersonic gunshot from a normal caliber firearm can be heard.

As for the lasgun, it is probably both severely ionizing the air (essentially the same thing lightning does) and most likely generating a distinctive high-pitched sound on impact because a high power laser pulse doesn't burn matter, it vaporizes it,

I thought one of the defining characteristics of the bolter was the ridiculously loud sound it makes, so I'd expect it to be really high. The Autogun seems okay to me, though in all honesty it's a bit abstract for me so I really have no idea. I know I used to live a fair distance from a military training facility, and you could certainly hear the ra-ta-ta on a quiet day. That was probably at least 10 kilometers.

Lasguns, far as I know, do make a really loud crack when you fire them, so that's probably okay (I've heard it described as a crack of thunder).

I'm not sure how it's described, but I assume these ranges are "huh, someone, somewhere, is firing an autogun right now" and not "oh hey, someone fired an autogun 9.5km away in that direction." Assuming very little background noise.

I do like that there's a chart for this though.

My personal interpretation is that lasguns make a noise somewhere between the crack of a whip and the whine of a flashbulb, a sound that's a little quieter than the equivalent auto gun, but still loud and distinctive. Plus I'd always thought of it as one of those sounds that loses its "attack" at long range quite rapidly, making it audible at distance, but hard to pinpoint a direction. That's a very subjective view, though!

Actually the bolter's distinctiveness is partly caused by half the noise being where it strikes; the detonating bolt shell. You get one bang at the muzzle and one bang from the target's face.

With mildly macabre perception you can probably more easily spot where the bolter came from.

I like that you can hear a throwing knife hit around 60 feet away. What are they throwing it at, a drum?

Plus the silenced pistol can be heard 100m away? They really need better silencers.

Silenced pistols IRL are audible at those distances. Silenced pistols in movies are more silent than a DH2 throwing knife thrown into the aforementioned drum. With the grimdark levels of technology, I guess the first one is the basis for this noise listing.

I would like to see some clarification, such as that this is the distance the noise is audible on a relatively flat plane, without background noise.

I would like to point out that in real life silencers may not completely muffle the shot, but they are designed so that it is difficult to determine the location of the shooter. I guess that is why they are known as suppressors not silencers. And they only work for single shots.

If you're silencing an SMG, yes, if you're silencing a .22 pistol, no. The knife throw example really does depend on what you are hitting.

From what I'm reading, all of these would have to be in dead silence and still air.

Agreeing with Baron. These sounds are in dead silence. You WOULD hear a knife that way. I hear arrows hitting a target 40 meters away, heck I hear the arrow moving through the air. But once people start talking they easily drone out the arrow.

Just take a small pin and drop it to a hard floor, like a tiled bathroom, in complete silence and you'll hear it.

And yeah, a .22 rifle/pistol is actually pretty silent when fitted with a suppressor.

Keep in mind that a silenced autopistol is still a silenced automatic. I'm less concerned about that than I am about that particular sound than the disparity between the autogun and the bolter.

Hearing someone crack a whip from a kilometer is a bit of a stretch. I understand the vaporizing/ionizing argument, but that's still a bit loud to pick out at that distance, even in silence.

I guess my groups will be taking stummers, or I'll just reduce the sound of a lasgun to about 500k.

Also, on this topic, is anyone else confused by the silent quality? The distance it can be heard from is reduced by X km. The Needle Pistol has Silent (5)...and it's range is only 80m. So...it can only be heard at a distance of -4920m? Same with the Long Las. According to the noise chart, a las burst can be heard 1km away, but the Long Las has Silent (3), so it's silent up to -2km away?

This is as bad as the old silencer rules which were something like "halve the normal distance they can be heard from," but those distances were never explained anywhere.

I would much prefer it be a penalty to Observe to notice the shot. Maybe something like -10 times the number in parentheses? That way a Needle Pistol is -50 to an Observe roll to hear it, and the Long Las is -30. Which would also give people more reason (besides toxic) to ever want a needler. It's the perfect assassin weapon, almost totally silent. And the Long Las would be very hard to hear, which makes sense. Thoughts?

Yeah, making it a penalty to Obeserve is how most other systems seem to handle suppressors in my experience, and it's really the only way that works particularly well. I like the idea of different weapons silencing to different levels, too.

Agreed. Making it an observe penalty makes sense - not only should it shorten the range you hear it at, but - if you did hear it - it should make it harder to locate the firer (as per stalker rounds).

A part of the hope would be to not add a new stat in simply for amount of noise. To make the system granular enough for all the vagaries of how loud weapons are would be rather complex for very little benefit. I dunno. Here's a thing because Saturday.

Range modifiers:

None for 0-10 metres

-10 for 10-100 metres

-20 for 100-1000 metres

-30 for 1000+ metres

Intervening terrain modifiers (can only be up to the range modifier except in special circumstances like soundproofed rooms):

None for open terrain (e.g. Along a stretch of empty highway, in the same room, in an open field of cut grass)

-10 for minimal intervening terrain (Light forest/undergrowth, an intervening wall or two)

-20 for medium intervening terrain (Dense forest with little undergrowth, a building, inside a transport to out)

-30 for dense intervening terrain (Dense forest with lots of undergrowth, a hill, etc.)

Background Noise modifiers:

+30 for no background noise (stummers, conversation, insects, rain, almost every everyday thing negates this)

None for light "normal" background noise (a few cars moving, conversation, rain etc.) (basically, there should be a good reason why the above case should be used)

-10 for medium background noise (Heavy, fast traffic, trying to hear something from the inside of a vehicle, hearing things while listening to an iPod, a normal party)

-20 for high background noise (pneumatic factory work with clanging and steel drilling, anything near supersonic stuff, a modern high intensity battlefield)

-30 for things that cause hearing damage (you are also firing a weapon, a really loud large concert, anything while you're asleep)

Loud (X): This weapon's bark is worse than its bite. It gives a bonus equal to ten times the number in the parentheses to hearing tests made to hear the firing of the weapon.

Silent (X): This weapon is silent, but deadly. It gives a penalty equal to ten times the parentheses to hearing tests made to hear the firing of the weapon.

Weapons Fire: When a weapon is fired (and is plot relevant), all characters may make a hearing based Awareness (Observe, Perception) test. The initial difficulty of the test is based on the availability of the fired weapon multiplied by -1 (basically, positive numbers become negative and negative becomes positive).* This is then modified by Range, Loud/Silent, intervening terrain, and background noise. Then consult this table, and remember that you get the benefits of every preceding result other than the fail one:

Fail: You fail to hear the weapon.

Pass: You are aware this weapon has been shot somewhere. You can make a deductive guess about range if you wish, it's not hard.

One degree of Success: You are aware of what this weapon is, assuming you are reasonably familiar with weapons fire.

Two degrees of Success: You are aware of the distance to the target within roughly rough 50% to 150% of the distance to the shooter. The GM chooses based on his own precepts of difficulty and ability of his players to separate character and player knowledge,

Three degrees of Success: You are aware of direction to within thirty degrees

Four degrees of Success: You are aware of the distance to the target within 80% to 120% of the distance.

Five degrees of Success: You are aware of the direction to within within five degrees (enough to make an attack without looking/being blind in melee)

Six+ degrees of Success: The character is aware of the distance and direction of the target. At longer ranges, this shouldn't matter as the target can move.

This may all seem a little complex, but honestly the GM should be able to judge roughly how "difficult" a thing should be without all of this stuff. My point is that while you can have a comprehensive hearing system, it doesn't mean you should. I feel like the vast majority of the time, it shouldn't matter, and that was a lot of typing for something that comes up maybe a few times during an investigation style campaign.

*This is based off the idea that more powerful weapons are both louder and more rare. Modify using Loud(X) and Silent(X) for particular cases like the Lasgun and Autogun, which are both relatively common but rather loud. Use range/intervening/background tables to figure out what number is "right"

Loud (X): This weapon's bark is worse than its bite. It gives a bonus equal to ten times the number in the parentheses to hearing tests made to hear the firing of the weapon.

I like this idea too. Though I imagine it would have to be relative to the class of the weapon, otherwise you would imagine every single heavy weapon would have some degree of the Loud quality. So for example, a hand cannon could have Loud (2), but that doesn't mean it's louder than a heavy stubber that lacks that quality. It's just louder than comparable pistols.

I could also see the Loud quality as being either incompatible with silencers or suppressors, or the silencer just removes the loud quality but doesn't give the normal penalties to hearing.

I really do hope they fix the Silent quality though. It's frustrating to have a totally pointless weapon quality, which is what it is right now.

This table is a mess. Warhammer is huge overkill. Bolter should probably be the loudest thing on there with the exception of the Earthshaker cannon. They're small rockets so how far away can you hear a firework? Lasguns? I actually didn't know they made a noise. It seems a bit Star Wars. Do they go "pew pew" ? (Joke - I saw the explanation that they make a loud crack above, but it seems weird to me).

You could get a noise from a laser blast super-heating flesh and fat. But it's still weird to me that they should make sounds audible a km away, even on a quiet day which is how I read this.

You can hear the firework exploding from far away (especially when they explode in the sky), but it's difficult to hear fireworks launching anything further than a couple of kilometres.

The lasguns making a "crack" noise has always been a thing. It helps 40k differentiate its "loud, scary, british" lasers from Star Wars's "pew-pew, slower-than-a-bullet, American" blaster bolts.

EDIT: Ever heard a lightning bolt? Lasguns do a similar thing (ionise the air it passes through) in a smaller, more directed fashion. Very loud.

What's with that credentials thing?

Also EDIT: Obviously the thing doesn't take into account everything, but I threw that together over half an hour or so during lunch.

You can hear the firework exploding from far away (especially when they explode in the sky), but it's difficult to hear fireworks launching anything further than a couple of kilometres.

The lasguns making a "crack" noise has always been a thing. It helps 40k differentiate its "loud, scary, british" lasers from Star Wars's "pew-pew, slower-than-a-bullet, American" blaster bolts.

EDIT: Ever heard a lightning bolt? Lasguns do a similar thing (ionise the air it passes through) in a smaller, more directed fashion. Very loud.

Well a Lightning bolt is a very, very powerful thing. I doubt even 41st Millennium tech sticks that sort of energy into a portable gun. But I take your point about scary British lasers vs. American pew pews. In fact put like that, how can I not like it? I think you just found the one argument that makes me happy for lasers to make loud noises.

What's with that credentials thing?

Oh, the user ak_37 keeps accusing me of lacking the "credentials" to know what's good or bad or to make informed arguments everytime I identify what I see as flaws in a rules proposal of theirs. They started demanding to know how long I'd been playing games and which ones I'd played, saying I lacked credentials. They clearly consider themself a "hard-core" gamer and have referred to themselves as such, saying things might be "okay for casual gamers" and rubbish like that. I alternate between finding it offensive and absurd so I put it in my sig to remind myself to treat it as ridiculous, not insulting. I've never made an argument based on me being more experienced than anyone else, so the experience I do or don't have is irrelevant. They accused me again in the 'Charge or be Charged' thread, yesterday.

Well, in my mind, plasma guns are portable lightning generators (literally, the lightning bolt is "plasma"), rather than the Halo-style plasma weapons. Lasguns also ionise the air, but are substantially smaller. But the effect they describe when a lasgun hits a target is similar to lightning bolts, just on a much smaller scale (say, a human limb bursting apart, rather than a whole tree). So yeah. Loud and proud. The physical beam would most likely be white hot.

Of course, when you talk about science and 40k, you're going to go to a bad place where people hit you with novelty vibrators, so it's something you shouldn't really worry about. Not sure how you could "stealth" a beam (for the long las). But the point is, lasguns are loud enough to hear from kilometres away, although are not as loud as an autogun.

On ak_37, this is a beta test with 'normal people' participation. Who gives a **** about "credentials"? Who even asks about them?

Well, in my mind, plasma guns are portable lightning generators (literally, the lightning bolt is "plasma"), rather than the Halo-style plasma weapons. Lasguns also ionise the air, but are substantially smaller. But the effect they describe when a lasgun hits a target is similar to lightning bolts, just on a much smaller scale (say, a human limb bursting apart, rather than a whole tree). So yeah. Loud and proud. The physical beam would most likely be white hot.

Of course, when you talk about science and 40k, you're going to go to a bad place where people hit you with novelty vibrators, so it's something you shouldn't really worry about. Not sure how you could "stealth" a beam (for the long las). But the point is, lasguns are loud enough to hear from kilometres away, although are not as loud as an autogun.

Well the crack of thunder is from the rapid expansion of suddenly super-heated air. A laser bolt shooting through it can justifiably make the same kind of noise (much smaller scale of course). I think I was wrong on this one.

In the really real world. the science of laser weapons is absolutely fascinating. There are designs for lasers that ionize the air between the weapon and the target and then deliver a powerful electric shock along the ionized path - essentially a tazer without the wires; there are "pulsed energy projectiles" which create a cloud of expanding plasma but only at the target - i.e. there isn't a path of plasma from weapon to target - it's the stopping point where the pulses 'pile up' (terrible science analogy warning) and create the expanding plasma which then explodes stunning the target and paralyzing the nervous system - get this: it's a "non-lethal" weapon design; and then there are pulse weapons which send a rapid series of pulses at the target designed to successively burn away the target and if you know what sort of target you are shooting (armour, flesh, whatever), you can adjust the pulse timings to devastating effect.

I saw a really good article on it a while ago, I'll see if I can dig it out.

Anyway, my statement on lasguns being quiet I now fully retract.

I always thought thunder was caused by the air rapidly filling in the space left by lightning.

on to something( slightly) more relevant I did find this -->

I think this is what knasserII is talking about.

https://www.youtube.com/watch?v=nBM71MyEdig

I always thought thunder was caused by the air rapidly filling in the space left by lightning.

It is. But the space is first created (I'm trying to avoid the word vacuum here) by the rapid expansion of air. Picture it as all that air around the lightning expands massively and rapidly as the mighty lightning bolt zaps through it. And then suddenly the lightning bolt is gone and you're just left with a great big volume of over-expanded air with the energy source gone and a lot of mean looking high-pressure air all around it waiting for vengeance. It all piles in and you get a clap of thunder. Or alternately it's Thor depending on your belief system.

I like your links, btw. Is that first one Sam Barros' Powerlabs? It looks like the sort of thing he would do. My favourite of his was the railgun which had something like a dozen capacitors the size of coke cans to generate high enough power. I built a rail gun myself once, long long ago, but it was nothing on that scale - just using three-phase AC power which is only a rail gun in principle. More of a iron rod mover, really.

Yes. The second one is what I was talking about. Although that one seems geared toward zapping cars and I was talking smaller scale for zapping people (as with a tazer). It would be awesome to cross the path of their laser with your laser so you could "steal" their lightning bolt. But in practice, it's hard enough just to time the laser and electrical charge together on your own gun, let alone someone else's. If you could just create a little old cloud of plasma in the way though, it would be like you'd thrown up a magic forcefield. They'd shoot their lightning bolt at you and it would suddenly hit a "wall" and turn into one of those old plasma globes you can still buy. It almost makes me want them to put these things into production just so I can invent some sort of hand-held plasma cloud device. I'd fling out my hand toward them and their lightning bolts would do fragment or fly away. But (a) the proliferation of non-lethal weapons is a bad thing because instead of getting used to replace lethal weapons as endlessly claimed, they end up getting used to replace not using weapons at all. And (b), what I would actually invent would undoubtedly be a method of badly burning my hand rather than making myself look like a Jedi.

Maybe instead I'll just carry a lighter. Then when they come for me, I'll just hold it under the sprinkler system and all their laser-tazer weapons will become useless. That's a good point worth noting by the way. You saw in that first video how he was using a bit of mist or dry ice in front of the gun. That's because you wouldn't see the laser otherwise - lasers being light that is all going in one direction, after all. The mist scatters the beam very slightly so you get some towards you. Now that is fairly clear, but what this highlights is how water vapour (or other particles in the air) can impact lasers. I don't know if heavy rain has ever affected the path of a bullet, but I've never heard of such. Lasers however, are pretty sensitive to such things. You might be able to have laser death weapons in Texas before long, but British police will be bashing us on the heads with truncheons the same way they've always done. You just don't want to be relying on laser guns in the rain and fog.

That mini-gun laser, btw? That's not anything good as an actual weapon design. That's just trying to make something that looks cool. You can tell by, amongst other things, the fact that it is doing a steady beam. Far, far, far more effective is a laser pulse. Here is a laser pulse pistol someone has built. Don't know how much it would hurt if it hit you in the arm, but it's much more along the right principles for a laser gun than the one earlier.