My theory of scaling down sounds in model trains.

JonMyrlennBailey

Active member
Let's assume that a full-size SD-40 locomotive has a whistle that is 140 decibels at 50 feet and can be heard up to two miles away by naked human ears on a quiet day.

Should the loudness of scale-model sound and how far it carries be in linear proportion to full-size sounds?

In G-scale, 1:22.50, if my theory holds correct, the whistle of a G-scale SD-40 should only be heard up to 433.33 feet away then. Divide two miles, 10,560 feet, by 22.50, G-scale ratio.

Decibels is logarithmic and nonlinear. It's not simple multiplication and division to calculate decibels value.

If a full-size train whistle is 140 decibels at 50 feet for example, I don't know what dividing that sound intensity by 22.50 would be in terms of a decibel value.

My theory for scale-model intensity level also holds true for all sound objects in scale modeling: animals, train engines, airbrakes, people, voices, church bells, vehicles, aircraft, boats, machinery, etc.
 
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Yup ... That's why they have a "sound volume control" wheel on your PC, a "Mute" button, and Audacity, so you can adjust sound files

I went to a model railroad convention and they had a trailer that had a diorama inside, with a 300w sound system that made the scene so realistically loud :cool:
https://youtu.be/hmmcgSgt5_c
 
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My concern is that model trains have the CORRECT sound level for their scale.

Do people here agree with me that sound loudness should be in direct proportion to scale ratio. Should a 1/10 scale train only be 1/10 as loud as a full-size train?

I was wondering if the model railroad hobby has ever employed serious sound engineers when designing their products.

I also believe a model train could have the doppler effect programmed into it. The whistle and diesel engine noise is higher pitched as it approaches the crossing and gets lower as it passes the crossing.

What is even more exciting to me about trains than what you see is what you hear.

Certainly in Trainz, sound levels can be fiddled with but Audacity is not a professional sound engineering program that will get all the sound objects in correct proportion by decibel count. For example, you might have a lawn mower on your layout. How much louder should a church bell be than a lawn mower? How should the loudness of a barking dog compare with a steam whistle?

A dog bark is how many decibels at 100 feet? A church bell is how many decibels at 100 feet? A lawn mower is how many decibels at 100 feet? A GP9 diesel locomotive is how many decibels at 100 feet?

I can set my fire engine parameters in edit config so that the sound distance is 100 meters but still it can be heard across a layout that is one scale mile wide.

Using various sound content items by various authors, I can easily create new custom sounds by substituting in new audio wav files and creating a new KUID for each and every one. I can have Bigfoot howling sounds, screeching mountain lions, lawn mowers, church bells, diesel trucks, the engine sounds of a Greyhound bus, etc. I can fiddle with parameters to try to adjust sound levels of each object as well.
 
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A 10 decibel reduction will result in a sound that is half as loud.

Your G scale sound is half the volume of a whisper.
 
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Actually ... All the DCC Sound Systems that I have heard, with a speaker in the tender (and such) are way too tinnish sounding, as the speaker is way too small

An HO or N scale train, with a cassette tape recording, played on a wall mounted 300W external sound system with four 15" woofers, sounds better to me

We used to have dust filtering down from the shaking rafters in our basement, and we had airport sound protection earmuffs on, with the stereo receiver on 85% full volume, that the neighbors called the cops to report a noise complaint, of a train station operating next door ... my neighbors hated me when we ran our HO trains, as the motors screwed up their TV reception

I think you put way too much thinking, deep concern, and worry, into these absurd threads

Maybe you should go to work for these companies, and change the way they do things

I seriously doubt that they have a team of dozens of Rokit' Sientist' lab workers in white, clean room suits, and with beard protectors, with dust booties, sweating all the small stuff in their sound lab

And exactly what difference in the world does it make to anyone, or to any company, in your "Poll" of the peanut gallery, as to these sound system companies products ? ? ?
 
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I still think Trainz sounds are much better than any physical scale-model trains on the market I have heard so far.

To be realistic, the sound of an object has to sound like it is being emitted directly from object. Hearing is directional.

I think with the large G-scale, 1:22.50, better quality sound-producing electronics, a larger diameter speaker, better amplification, can be installed concealed on board moving vehicles. Even some Lionel O scale have sounded tinny to mine ears.

If I were a billionaire striving to have the most advanced and most perfect physical model train layout in the world, a lot of time and money would be invested in sound engineering technology to make the whole layout sounds as real as possible.
 
In theory if sound amplification was linear this would make sense, but sounds are amplified on an logarithmic scale. As was pointed out above, if we were to scale down the sounds of realistic locomotive engine to that in relationship to the scale size of a model train, many of the sounds would become whispers or imperceptible as the scale becomes smaller. There are somethings that don't scale well and sound is one of them.

The sounds we have in our virtual world are only as good as the original recordings they are derived from. If someone recorded an engine sound, using that example again, at too high a volume or too close to the source, the sound will be clipped due to going beyond the range that the electronics can handle. Clipped sounds are distorted and sound "hot" as they say due to the electronics being unable to handle the range.

Recording good sounds also takes more than just top-end equipment. There are people that go to sound-recording technology school to become recording engineers. This is a very expensive and very, very intensive training program with lots of complicated maths and engineering stuff that goes well beyond what can be explained here.
 
If I were a billionaire striving to have the most advanced and most perfect physical model train layout in the world, a lot of time and money would be invested in sound engineering technology to make the whole layout sounds as real as possible.
Well you are not a billionaire

Is this the most pressing, all important thing going on in your world to sweat over ?

I can think of a billion world news current events playing out right now, that are threatening to end our very human existence ... as you ponder your deep concerns of great worry about model railroad sound systems quality being proper, posting on a Trainz simulator forum, that has absolutely no relevance whatsoever to Trainz, nor to Trainz model railroading

[h=2]Definition of theory [/h] 1 : a plausible or scientifically acceptable general principle or body of principles offered to explain phenomena the wave theory of light

2a : a belief, policy, or procedure proposed or followed as the basis of action her method is based on the theory that all children want to learn
b : an ideal or hypothetical set of facts, principles, or circumstances —often used in the phrase in theory in theory, we have always advocated freedom for all

3a : a hypothesis assumed for the sake of argument or investigation
b : an unproved assumption : conjecture
c : a body of theorems presenting a concise systematic view of a subject theory of equations

4 : the general or abstract principles of a body of fact, a science, or an art music theory

5 : abstract thought : speculation

6 : the analysis of a set of facts in their relation to one another
 
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Oh my god who cares. Are we seriously having a discussion about weather or not you should be able to hear you G-Scale SD-42 from 500 feet away? :eek:

However I do agree that DCC Sound Value is really dumb because it doesn't sound good at all it is totally tinnish.
 
Gentlemen.

I think your replies are wrong, Jon appears to have the type of mind that discovers things by considering and seeing what appears to others as unimportant or trivial. Without minds like that, we would not be able to discuss this here, our modern world would not exist.

Peter
 
So what is to be the end product outcome of this thread ? That a petition to LGB, Bachman, SoundTrax and Tsunami be filed to change the way they are doing business, and that they should alter their design, production, and assembly line, just because one guy that has the bright, middle of the night, obtuse, eccentric, spontaneously sit up in bed dream idear' says: "you are doing it all wrong", "and should add Doppler effect and my sound recommendations" ... Sounds like yet another pointless dead end "complaint thread" YAPDECT
 
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I also believe a model train could have the doppler effect programmed into it.
The doppler effect is dependant on the relationship between the source and the observer. It can't be produced in the source. What would be right for someone standing at the crossing would be completely wrong for someone at a different location.

Certainly in Trainz, sound levels can be fiddled with but Audacity is not a professional sound engineering program that will get all the sound objects in correct proportion by decibel count.
Audacity is a tool. It can do what you want, but you have to know what you are trying to achieve. In this case all that is required is a correct sound level and the correct distances specified in the config. There is no need for calculation - just do it by experiment.

If you research your topic a bit before posting these random thoughts you will have a much higher chance of sensible replies.
 
These are the sort of views the OP should be posing on a personal blog or Facebook, "What's on your mind..." not a Trainz forum.
 
Would Z scale have the sound so quiet that there would be no sound at all? Inquiring minds want to know:confused::cool:

edit: sp
 
I'm including asking questions and getting feedback from my concepts presented here on Trainz as part of my research. To me how things SOUND is fascinating in this hobby while others might find it trivial.

I'm no physicist, Einstein or Thomas Edison, but I do have creative and inventive mind. In Trainz, we have the doppler effect built into the software but how could this be possible for a physical model train layout in scale?

Well, one could design a model layout whereby the people in the train room are wearing headsets to hear the various sound effects of the layout. Sophisticated electronics by my own speculations could sense the exact position of the person wearing the headset so the proper sounds would be presented to the listener wherever he is standing in the train room observing the layout.

If two people were standing side by side, they would more or less hear the same sounds through their respective headsets. If somebody were standing close to a church, he might hear tolling bells and the volume level would be in relation to how far he were standing from the layout scale-model church. If somebody were standing near a lawn mower, he would hear buzzing. If somebody were standing near a crown of children at a school, he might hear laughter. At train station platform, the clamor of people talking. Near a dog, barking and growling just as in Trainz. And so on, all relative to the observer's location in the room. Ideally, sounds should be directional and vary in intensity. The sophisticated headphone train sound system I fancy might even sense the direction the wearer's head is facing. Something like audio virtual reality.

If he were to be standing near a crossing on the layout and a train was approaching, he could conceivably hear the doppler effect because the system would know his point of view and would present the appropriate sound effects for him to hear through his headphones. Yes, I have an Texas-size imagination like Walt Disney. My fantasy is to Disneylandize model trains. To make them look and sound as real as it gets. The headsets worn in the train rooms would also eliminate the tinny-sounding devices on board model trains as well. The trains would be physical while the sound effects of the entire layout maybe could still be virtual. The sounds themselves could be computerized.

Perhaps, yes, I should present these sounds concepts to a physical model train discussion board. Yes, it is true we get more realistic train sounds in Trainz than most physical model railroaders do for their own respective hobby equipment. Although the virtual images on a PC screen we get while playing with Trainz aren't nearly as pretty as the sights a high-quality physical layout, we are blessed with much better sounds as a consolation. Physical model train people don't get frame stutter either while viewing their physical trains.
 
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