selector wrote: I agree with this largely. It would be helpful for our hosts, Kalmbach, to have a credible article put this into perspective for modelers. Let's face it, sound in engines is here to stay. It will get better, but it will cost us more to get there. That's the simple stuff. But why don't the manufacturers go the extra step and suggest ways to get the most out of this really nifty modeling experience? Why not caution the user about volumes in excess of 60% of the system's engineered capacity? Why ship us QSI decoders maxed out in volume so that the speakers crackle and distort the sound that is meant to impress us? Why!!!?
I agree with this largely. It would be helpful for our hosts, Kalmbach, to have a credible article put this into perspective for modelers. Let's face it, sound in engines is here to stay. It will get better, but it will cost us more to get there. That's the simple stuff. But why don't the manufacturers go the extra step and suggest ways to get the most out of this really nifty modeling experience? Why not caution the user about volumes in excess of 60% of the system's engineered capacity? Why ship us QSI decoders maxed out in volume so that the speakers crackle and distort the sound that is meant to impress us? Why!!!?
This is something I very much agree with. The sound from the speakers are just to loud. I've begun a project now as soon as I change the address of a loco I also turn the volume down to about half. it sounds much better. On maximum it gets loud and there is a lot of noise basically. It is not impressive to crank it out loud but it's like kids with a new stereo, it is often not the quality but volume that impresses people.
I recently got an Athearn Challenger. That thing is so loud I can't stand it. If I sit down to close it I want to throw in to the wall. And there is no Central volume control, the manual says a small screw on the tender but I can't find one. They really should set the sound to about 40-60%. The problem only worsens with each engine you got on the layout.
There are small speakers nowadays that can produce relatively large amounts of base. But they are very expensive and would also as someone pointed out use to my juice to be worth using. And when I say expensive I mean that you would but the speakers and you get an engine to go with it. But there are great small speakers now a days.
Magnus
davidmbedard wrote: Scale the sound people....scale the sound. Go stand 300 feet from a rail line and take a listen. David B
Scale the sound people....scale the sound. Go stand 300 feet from a rail line and take a listen.
David B
You can't hear a diesel switcher idling from further back, especially in bush, than about 150m. Get close, and sure you'll get that nice sub-woofer effect. But on our HO layouts, 150m is just over 2.5' (not calculated, just off the top). Will our analog ears notice that a QSI SW8 sound different from another on the far side of the yard? Well, if they're both set near their maxes, not much they won't. Turn down the volumes to something nearer 50%, though, and you will notice something of a difference.
You won't for the same scalar reasons with subwoofers spaced 10 feet apart. It'll all just be a deep rattle.
1. The air absorbs and dampens high frequencies, not bass. That's why thunder, heard at a distance, is all bass component.
2. Making bass is a matter of moving large quantities of air, which requires large speakers, which require massive amplifiers. Never going to happen onboard model trains.
3. Bass is omnidirectional, treble is unidirectional. That's why home theaters and 5.1 sound systems have many small satellite speakers for the high end, but only one subwoofer. For improved frequency response in model train sound systems, you don't need block detection. leave the high frequencies onboard, feed the bass to a stationary subwoofer, and you ears will "cause" the bass to follow the train around the track.
4. There's a technological hurdle involved in doing sound this way. The sound signal source is in the decoder, on the train. That electrical signal either has to travel along wires to the subwoofer amp and speaker, or else you have to use two decoders, and make sure they stay in perfect sync. If you reverse the wires on one speaker in your home stereo, one speaker will be pushing, while the other is pulling. They cancel each other out, in strange ways. The effect can be weak, tinny sound, or it can be an effect called comb filtering, which just sounds strange.
Trying to feed an audio signal through the rails will interfere with the AC power already running there. Bass is typically defined as being those frequencies between 20 and 125 cycles per second (hertz). Standard power line alternating current is right in the middle, at 60 hertz. No idea what frequency DCC power signals alternate at. There are also bandwidth issues to contend with, and in the case of multiple trains operating simultaneausly, these problems are compounded.
You could transmit the signal wirelessly, if you had room for a transmitter in the model, and were willing to suffer audio degradation in a high RF environment.
Most likely solution is going to be two decoders, one onboard, one stationary. A much lower bandwidth timing pulse should be able to keep them in sync well enough to avoid most audio problems. If both decoders were slaves in the timing arrangement, and the "power pack" was the master, then the onboard decoders would not have to generate the timing pulses. However, they would have to respond to the timing pulses, and therefore, all yoour onboard sound decoders would have to be replaced.
5. Yet another significant issue exists. The tiny speakers onboard trains don't just fail miserably in producing bass, they also fall well short of the mark in midrange frequencies. These frequencies are those that the human ear is most sensitive too, and their absence will not go unnoticed. If you try to send these to a stationary decoder, then you lose the effect of omnidirectionality, and have to jump through complicated hoops to make the sound move with the train.
6. Finally, you have the problem of the sound samples stored in existing decoders. Every bit of audio data takes up storage space. 8 bit samples are roughly equal in quality to the sound quality of a telephone. Moving up to 16 bit samples halves the decoder's storage space. often the samples themselves lack bass, since the speaker can't reproduce it, and the manufacturer chose to maximize storage space usage. If the bass never existed in the original sample, or the decoder manufacturer EQed it out before burning the sample to the chip, it's gone, and you can't get it back.
There's another way, much simpler, and it deals with every problem listed here, plus those of modelers who complain about hearing trains in tunnels, and on the far side of the layout and the cacaphony you hear when several trains run at once.
Typical prototype experience begins with no audible train noises,, then you pick up the bass, and perhaps the rails singing, then a rapid gain is sound pressure levels, to or above the audible pain threshold, a doppler shift, and then a rapid decline in locomotive noise, while the clackety clack of wheels on rail splices continues till the train is past.
At a given "viewing point", stereo samples at 16 or even 24 bit fidelity, play back through a standard stereo pair of fixed speakers, when trains roll past. To accomplish this, you need no more than an old computer with soundcard, speakers to match your preferences in quality, and a copy of the Winamp software. The sounds are easily triggered manually from a keyboard, and with a small additional investment, could be triggered automatically with crossing dectectors, though you'd have to write a bit of your own software to make that happen. Nothing major, the computer will know when the digital trigger is tripped, you just have to tell it what to do at that point.
Since the average layout compresses so much railroad into a much smaller space, I think the ultimate solution will end up being a hybrid of the techniques described so far, and some others. In my opinion, the PC figures largely into most or all of the sound issues. The PC's CD player can play normal background sounds, birds, weather, traffic wildlife, machinery, etc. It can also hold, trigger and play back sparkling CD quality digital bypass samples, through a full range sound system.
Raising the bar a little higher, a PC is easily equipped with a 5.1 soundcard, and attached to a THX quality speaker array. With this setup, and about $100 in commercial software, DVD background audio and triggered train bypasses can move with the train or other sound source in three dimensions, though the sound's spatial distribution and movement will be specific for each layout.
Having had a ringside seat through the invention and development of both MIDI and digital audio technologies, my assessment of current DCC onboard sound is that it's currently well short of prime time.
If your goal is high quality audio, either at 1:1 volume levels or at scale values, prototypical fidelity on a level to match your model's and layout's fine detail, odds are you'll almost certainly have to replace your existing decoder investment, and possibly your control infrastructure as well.
I'd say you'll see a completely new set of standards within ten to twenty years from now. There is much work being done in the field, but the first step is to field a system that works, at the much higher audio standards, then as competitors enter the market, there will be a period of struggling for dominance in those markets, and eventually a victor will emerge and a general standard consensus reached. That takes time. If there's not a market for high end audio, it will never take off. I think there is. I remember well when the primative ancestors of DCC first appeared and the debates that raged way back then. Today, most modelers wouldn't even think of running their layouts on DC. Tomorrow, the elite will sneer at 8 bit onboard only audio. The current trend shows audio expense increasing at near exponential rates, and the market is clamoring for more sound, not less.
If you're interested in building a first class railroad , with first class sound, now, and don't want to wait for that long, the first place to begin is by integrating a PC in the audio chain as early as possible. Be prepared to think outside the box and solve some problems yourself, because the infrastructure and COTS equipment isn't in place yet.
davidmbedard wrote:Scale the sound people....scale the sound. Go stand 300 feet from a rail line and take a listen. David B
True. If our trains were truly part of a miniature universe, then the sound waves would be scaled down as well. That would result in shorter (higher) frequencies, to our ears. I've heard people running big sound systems with a lot of bass for their layout sound effects, and I thought the effect was kind of lame. IMO, there's a big disconnect between 1:1 bone-rattling bass, and that tiny little loco pulling its train around your pike.
Maybe a compromise could be reached somewhere in the upper bass frequencies, but it's not that easy to achieve for reasons stated previously. The original sound samples must have low-end as well, and I don't think anything the manufacturers are putting in these chips come close to that.
Nelson
Ex-Southern 385 Being Hoisted
I have, there is still much more rumble and clank than clickity russssshhhhhh.
( and depending on the terrain, quite often it can still be felt through the feet ).
Under table subwoofers,
Better make sure your scenery is glued down good.
doc manago wrote:In order to have more and better bass, I can´t understand how, in 2007, no DCC manufacturer developed a better speaker, heaviest, with an important magnet and Kevlar cone, not the cheap and thin thing that they are today...! What do you think?
The speaker quality isn't necessarily the issue. There are some really great speakers out there (do you want to pay $60 per speaker per locomotive?), but even the best won't produce what you are wanting. Reproduction of bass is a matter of moving a lot of air. There isn't physically anyway to move that much air from an HO or N scale model. As the prior posted mentions it is probably a matter of getting off-unit speakers that are activated by the location of the train on the layout. Even then it is more than speakers, the sound processor manufacturers would have to start making units that could produce that low of a signal on their outputs. Today they don't even worry about trying to make those frequencies because they know no on-board speaker would be able to reproduce them anyway.
doc manago wrote:In order to have more and better bass, I can´t understand how, in 2007, no DCC manufacturer developed a better speaker, heaviest, with an important magnet and Kevlar cone, not the cheap and thin thing that they are today...! What do you think? Bye.
In order to have more and better bass, I can´t understand how, in 2007, no DCC manufacturer developed a better speaker, heaviest, with an important magnet and Kevlar cone, not the cheap and thin thing that they are today...! What do you think? Bye.
What we need (and I am serious) is a subwoofer system for DCC. Then the little speaker in the loco can put out directional high range sound while the unidirectional bass rumble would come from under the layout.
This is how 5.1 systems work.. it would be fantastic for layouts. A large layout could combine several subwoofers with a block detection system to move the rumble to the part of the layout room the loco is occupying.
Since my room is small and I use N-SCale.. I would like to take it farther and combine block occupancy detection with sattelite speakers at the different scenes to carry the high range of sound as well. A computer running DCC software and a surround mixer should be able to do this with the right software..
Regards,
Chris
I think there is a real good reason. They cost more and people are already complaining. Thick is also a problem when it comes to diesels and electrics. In steam they could put in thicker, heavier speakers with no problems, at least the bigger steam engines.
But people are already complaining about the price they pay for sound units so I do not think that an even larger price tag is the solution. Usually the sounds are to noisy anyways and it's better to just let them make a little noise in the background.
Doc,
I'm sorry, but with all your DCC-related posts this week, I can't help but think of this scene:
"I want an Oompaloompa NOW, Daddy!!!"
Just kidding...! I'd used this on another board, but it seems to fit here too...!
Modeling the Rio Grande Southern First District circa 1938-1946 in HOn3.