How quiet is it?

[garrowolf]

I think you can skip the decibel column on the chart, and just go with similarity. "If it sounds about as loud as ... use DC ...".

But how would that be any different? Part of the point was so someone could put in sounds that I didn't have.

 

[Olgar Shiverstone]

But how would that be any different? Part of the point was so someone could put in sounds that I didn't have.

Frankly, it's simpler. Most people are not acoustics engineers who walk around with decibel meters so they can measure how loud things are.

Unless you're trying to re-create Rollmaster, apply Occam's Razor whenever possible.

 

[garrowolf]

Okay I fixed it.
Anything I missed?

 

[pawsplay]

Okay I misunderstood what you were talking about. It is an interesting effect however it is a little too technical for my game.

If that's too technical then you can jettison the db scale. Every time you add complexity, it should add fun to the game. Either the complexity needs to be fun, or the complexity should be justified by adding something to the game that is fun. Using a decibel scale, independent of other, much more important factors, adds a fair amount of detail while adding very little realism. And measuring db levels is really outside the normal game activities, so knowing the db level itself isn't very interesting.

Which is "louder," your friend trying to shout something to you at a rock concert, or turning on the TV in a quiet house?

 

[El Mahdi]

I think an aspect of sound that's being ignored, and that Umbran hit on though didn't specifically label it, is the frequency of sound. The brain differentiates sound based on volume and frequency - with both being equally important (neither dominant).

In general and only taking into account volume (dB), the science that's been presented in this thread is spot on - but it's not the whole story.

For the most part, it takes a certain range of volume increase over ambient before a new sound is detected - but only if they are basically the same frequency. If your ambient noise is at 50db, but it's mostly in the middle frequency range, and there's suddenly a very high pitched sound - it does not have to exceed 50db to be noticed.

I don't know the science for this but it seems to me that the larger the difference in frequency, the lower the db threshold necessary for detection. Though a really loud sound can still drown out any new sound - so there's a threshold there also (like if you're standing next to a running jet engine - it doesn't really matter what frequency or volume the new sound is).



Although not scientific, some personal examples are:

• With older "tube" tv's I can hear the very high pitch of the tube when the tv is turned on - even in a fairly noisy and crowded room. The sound itself is not very loud (low db), but very noticeable to me because of the high pitch (frequency).
• In a quiet house with consistent ambient noise (such as a central air system), I can oft times hear someone come up behind me due to changes in the ambient noise (pitch and volume), and not due to them actually making a discernible noise themself (the pitch and volume of the ambient noise shifts due to their position, kind of like varying the length of a resonating tube).

Now, how to model that is another story. But modeling a mechanic with only db as the contributory factor creates an unrealistic mechanic (if realism is what you're shooting for).

 

[garrowolf]

I think that frequency is a bit too much for a game. I was just going for something a bit more complete then the list that they have in the SRD.

 

[El Mahdi]

I understand, it would be more complicated. And technically, a persons Move Silently and Listen scores would take into account knowledge of such things (and combine it into their scores as an abstract quantification).


But, like some of the others above, I'd reccomend removing any mention of db levels and just using the sound descriptions in an increasing manner (whisper < normal conversation < military jet) with the associated DC modification. But then also include under your general conditions (where you have Range to Hear and Barrier to Hear):

• Consistent low to mid volume ambient noise level (white noise) = -10 to Listen/Notice Check DC (or +10 to Move Silently Check)

Noticing a sound is about differentiating from other sounds. So it's as much what isn't there as what is there. A consistent background sound can make it much easier to notice someone. Sometimes even easier than if the environment was dead silent.

 

[garrowolf]

check the original link. I did change it.

 

[El Mahdi]

Ooops...Sorry


By the way, I liked the character examples. It helped quite a bit in understanding your system.

I don't think it's quite my cup of tea, but it's really starting to shape up nicely. Looks good Man.

 

[garrowolf]

Ooops...Sorry


By the way, I liked the character examples. It helped quite a bit in understanding your system.

I don't think it's quite my cup of tea, but it's really starting to shape up nicely. Looks good Man.

Thanks! Now I've just got a few more hundred little details to work out and I'll be finished!