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Better speakers, please !

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Better speakers, please !
Posted by Harley-Davidson on Friday, September 14, 2007 3:10 PM

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.

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Posted by Dave Vollmer on Friday, September 14, 2007 3:14 PM

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...Big Smile [:D]!  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.

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Posted by Lillen on Friday, September 14, 2007 3:21 PM

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.

 

Magnus

Unless otherwise mentioned it's HO and about the 50's. Magnus
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Posted by ChrisNH on Friday, September 14, 2007 3:22 PM
 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.

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 

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Posted by Gandy Dancer on Friday, September 14, 2007 3:43 PM

 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?
You don't really want to know what I think.....but I'll tell you what I've learned over the years.

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.

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Posted by cacole on Friday, September 14, 2007 4:06 PM
It's not just a question of better speakers, but also of the wattage needed to drive a speaker.  The power output of sound decoders is limited by the availability of amplifier microchips that are reasonably sized without requiring large heatsinks.  And the cones on speakers small enough to fit inside model trains are too small to move air at low frequencies.
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Posted by Greg H. on Friday, September 14, 2007 4:58 PM
I've been thinking about this even since I started getting involved with hobby ( all of about 4 months now Big Smile [:D] ) and I believe that ChrisNH, has the answer right on the nose.    Under table subwoofers, with on board speaker for the high range sounds. 
Greg H.
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Posted by loathar on Friday, September 14, 2007 5:15 PM

Under table subwoofers,

Better make sure your scenery is glued down good.

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Posted by Greg H. on Friday, September 14, 2007 5:39 PM

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 ).

Greg H.
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Posted by SteamFreak on Friday, September 14, 2007 5:41 PM
 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.

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Posted by jeffers_mz on Saturday, September 15, 2007 1:16 PM

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.

 

 

 

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Posted by selector on Saturday, September 15, 2007 1:43 PM
 davidmbedard wrote:

Scale the sound people....scale the sound.  Go stand 300 feet from a rail line and take a listen. 

David B

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!!!?

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.

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Posted by Lillen on Saturday, September 15, 2007 3:59 PM
 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!!!?

 

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

Unless otherwise mentioned it's HO and about the 50's. Magnus
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Posted by rrinker on Saturday, September 15, 2007 4:15 PM
 davidmbedard wrote:

Scale the sound people....scale the sound.  Go stand 300 feet from a rail line and take a listen. 

David B

 

 Very true. I think on a larger layout with 6-7 trains runnign during an op session, if you could hear ALL of the locos anywhere in the room it would quickly get annoying. Standing in one spot, you should hear a train as it approaches your location and as it departs, btu not when it's a scale 20 miles away.

 

                                    --Randy
 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Greg H. on Saturday, September 15, 2007 7:15 PM
 jeffers_mz wrote:

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.

Good ideas.

I had this visi

Greg H.
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Posted by selector on Saturday, September 15, 2007 7:47 PM

Magnus, either the tender cover lifts off and you'll find the master volume screw, or one of the covers comes off...maybe the water filler hatch must be pryed off with a sharp blade wedged between the cover and the deck?  Don't the instructions have an exploded diagram showing the cover that comes off?

-Crandell

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Posted by chessiecat on Saturday, September 15, 2007 8:54 PM

I ordered a pair of what they call High-Bass speakers from Tony's. They have a heavy metal cone and a large gasket that it floats on. I got both sizes, a 1.10 inch and a 1.06 inch speaker but the enclosures for them are on backorder. I was going try to hook one up to my Tsunami I installed in my Allegheny but then I ended up being selected for a jury. Hope that it ends this coming week. The speakers look to be thicker than most at least a half inch so they may be a little hard to squeeze in the tender.

Thanks Jim

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Posted by accord1959 on Saturday, September 15, 2007 9:53 PM

 Greg H. wrote:
I've been thinking about this even since I started getting involved with hobby ( all of about 4 months now Big Smile [:D] ) and I believe that ChrisNH, has the answer right on the nose.    Under table subwoofers, with on board speaker for the high range sounds. 

If layouts had subwoofers placed at various locations underneath, you'd have to compete with the youngsters stopped at public crossings at grade with there subwoofers blaring. I think it's a great idea, what is missing is the rumble of the prime mover as the loco rolls by and I think a subwoofer under the layout would definately replicate that sound.

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Posted by Don Gibson on Saturday, September 15, 2007 10:02 PM

IT'S SIMPLE.

SMALL speakers cannot create enought bass to virate your eardrums. it's the Laws of Physics. Neither can a 'knothole' allow enought light in to illuminate a room.

Speakers are 'Transducers' - a disk or megaphone of sorts that vibrates the air. 1. Your ears hear 'air' vibrations - nothing more.

2. Bass (moving air) is expen$ive. A 30 foot air column will produce 'bass'. Pipe Organs have a raft of these, so will a $500+ subwoofer with a large cone driver. Computer speakers won't do it. Metal cones won't either, nor 'bottle cap' enclosures (both reinforce the highs)\.

3. Want bass on the cheap? (A pair of good stereo headphones - around $50) - provided you have 10 watts of amplifier to drive them.

1" speakers with a 1 watt amplifier won't cut it, however SOMETHING is better than nothing, Yes?

Don Gibson .............. ________ _______ I I__()____||__| ||||| I / I ((|__|----------| | |||||||||| I ______ I // o--O O O O-----o o OO-------OO ###########################
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Posted by Don Gibson on Saturday, September 15, 2007 10:52 PM
 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.



Doc:

Speakers are 'Transducers' ie: an (AC) mechanical devices that change one form of energy into another.

DC is Electrical Energy

DCC is Digitalyl Encoded information imbedded in DC, that a Decoder translates to the motor.

Digital transmission is HERE.(As you'll discover in 2008 or 2009 when your TV's won't work).

MODEL TRAINS are miniatration. Small speakers move little air. Your EARS only hear air in motion.
BASS means much air in motion. mzJeffers is right on.  Bass is 'pumping air'. Muscles are acheived by pumping Iron.

If you want BASS it Co$ts money. HOW MUCH are you willing to spend?????????????????????

A speaker that produces AC analogue signals will not work on DC - nor will Digital transmission run a DC motor - nor do ANY DCC manufacturers manufacture speakers! Even QSI / Lok Sound /and MRC buy theirs.

YOU appear to want the moon, but can you pay for the rocket fuel to get there? If not you're out of gas.

Don Gibson .............. ________ _______ I I__()____||__| ||||| I / I ((|__|----------| | |||||||||| I ______ I // o--O O O O-----o o OO-------OO ###########################
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Posted by jeffers_mz on Sunday, September 16, 2007 2:45 AM
 Greg H. wrote:
 jeffers_mz wrote:

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

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Posted by electrolove on Sunday, September 16, 2007 2:52 AM
Just want to show you guys a link:

http://www.qsisolutions.com/products/q-hb_speaker.html


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Posted by Lillen on Sunday, September 16, 2007 3:43 AM

The better speakers that are now available and that Electrolove links to is the thing. To many people puts width and size as the same thing. When comparing Bass output this have often been thing. But, it's the amount moved that is important. This can be achieved by letting the speaker pump it out by having a greater depth rather then width. Unfortunately I don't know the English words for this since my audiophile nature is taught in Swedish.

 

But basically. In a large tender, like a Big boy or something you could have a very deep speaker. It's width would be the same as today but the volume of air being pressed out would be greater since the speaker would be able to move a lot more if you have these new things.

 

Magnus

Unless otherwise mentioned it's HO and about the 50's. Magnus
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Posted by electrolove on Sunday, September 16, 2007 5:46 AM
Magnus, you are absolutely right. It's all about moving air. As much as possible.

 Lillen wrote:

The better speakers that are now available and that Electrolove links to is the thing. To many people puts width and size as the same thing. When comparing Bass output this have often been thing. But, it's the amount moved that is important. This can be achieved by letting the speaker pump it out by having a greater depth rather then width. Unfortunately I don't know the English words for this since my audiophile nature is taught in Swedish.

 

But basically. In a large tender, like a Big boy or something you could have a very deep speaker. It's width would be the same as today but the volume of air being pressed out would be greater since the speaker would be able to move a lot more if you have these new things.

 

Magnus

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Posted by howmus on Sunday, September 16, 2007 12:43 PM

electrolove, that was a fasinating link.  Traditional speakers used in HO sound have been Tweeters from the standard two or three way home speaker systems or the same speakers used in headphones.  The issue is not only the amount of air to be moved to produce a bass response, but the actual ability of the speakers to be able to vibrate at the low hertzes, although the two are very much related.  In a small enclosed space, such as headphones, small speakers can reproduce bass without a problem as it is a very small acoustically perfect space inside the headphones on your ear.  Take off the headphones, put them on the table and then listen to the sound and you have what has been produced by HO on board sound.  Very tinny as the bass is missing.  That is the first problem in action. 

It looks like the new design may be a major step forward in authentic sound for us.  However, note the increase in power needed to drive the speakers (as would be expected to be able to move enough air) to create better sounding Bass.  That article did a great job of explaining what the problem is BTW as well as showing how the new design will help correct it. I may have to rethink my avoidance of Sound in the hobby if this actually works and they keep moving forward with the technology!

Ray Howard, owner

Howard's Music Service 

Ray Seneca Lake, Ontario, and Western R.R. (S.L.O.&W.) in HO

We'll get there sooner or later! 

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Posted by Lillen on Sunday, September 16, 2007 12:49 PM

This can get as complicated as one wants it to be, the quality of the membranes are important, the cone and so on. Let's not forget the casings, they are extremely important to the quality of small speaker sound. If you design a large tender as a vessel for a superior speaker you could create a very good one. But it would eat a lot of juice and would make it very expensive. As I said before, the speaker would come with a train, not the other way around.

 

I've listened to extremely high end small speakers and the sound is superb. Of course, when it comes to bass it can not beat a sub woofer. Then again, I've seen small sub woofers have a lot more bass then a larger one due to the way they are built and encased.

 

 

Magnus

Unless otherwise mentioned it's HO and about the 50's. Magnus
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Posted by jeffers_mz on Sunday, September 16, 2007 1:29 PM

 electrolove wrote:
Just want to show you guys a link:

http://www.qsisolutions.com/products/q-hb_speaker.html


 

By the specs given, this speaker will give you an audible improvement in sound, but not much extra bass, if any.

Defining "bass" is a subjective realm, in more ways than one. Depending on who you listen to, bass frequencies begin between 125 htz and 250 htz, descending from there. This speaker rolls off sharply beginning at 310 htz,

The smallest noticable increment in sound pressure levels (loudness, roughly) is about 3 decibels. Three of these smallest perceptible increments will result in a perceived doubling in loudess, about 10 decibels.

This speaker's performance shows a ten db drop at the upper end of the bass frequencies, rapidly dropping to zero just below that. In other words, the upper limit of what some call bass and what other's call low midrange, will be half as loud as the normal range of the speaker's output, with nothing beneath.

All is not lost, however. If all you're after is bass, you're still out of luck. But many people's complaint with onboard sound is the whiny, nasally quantity of the sound produced. Believe it or not, terms like "nasal" have actually been defined, at least in the general sense, in the recording industry and we know where they live.

Before getting too far into that, there's an important principle to understand. A speaker with a perfectly flat (same loudness) frequency response from 20 to 20,000 cycles per second would not be perceived as flat by most people. Evolution has "tuned" your ears to hear the frequency range associated with human speech easier than other frequencies. More specific, evolution has favored the offspring, of parents so tuned to the frequencies at which babies cry, that it is mentally or physically painful. 

So two things are working here to make your trains sound less pleasing.

One, the speakers tend to roll off below 300-500 htz, just below "nasal, at around 800 htz. "Nasal" is the lowest frequency produced by most small onboard speakers. Your ears hear higher frequencies less well, so "nasal" is the loudest perceived frequency band small train speakers produce.

Two, one million years of evolution has pre-selected you to exist  and thrive, IF the nasal frequencies so irritated your parents that they were willing to take action when you cried.

"Nasal" IS the loudest frequency produced, and since nasal is the loudest you normally hear, you end up with "nasal times two".

By filling in the lower end of the midrange spectrum, and delving into upper bass registers, not only will this speaker sound less nasal, TWICE over, but it allows you to EQ the output to even furtherreduce the strident nasal frequencies. Not you actually, unless you are recording your own samples or have an EQ built into the decoder, but this can be done in the design and manufacture of the decoders.

While you might not see any improvement in bass response at all, I am reasonably confident you will like the sound MUCH better, assuming of course, that the decoder sound samples and circuitry design take advantage of these new output capabilities..

 

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Posted by electrolove on Sunday, September 16, 2007 2:06 PM
So you mean that this is a simple way to fool us all?

I do not understand the EQ thing you are talking about. How can a EQ make the bass any better if the speaker can't reproduce it?
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Posted by selector on Sunday, September 16, 2007 3:28 PM

EL, I think he means the bass is a gonner anyway, but you can reduce the nasal reproductions in what the speaker will produce in abundance, and coincidentally what your ear is likely most selectively attuned to, by equalizing their volumes downard a bit...thus enhancing the somewhat higher freqs that will tell us we have improved sound in our tenders?

Did I get that right?

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Posted by Don Gibson on Sunday, September 16, 2007 4:46 PM

How can a EQ make the bass any better if the speaker can't reproduce it?

It can't. 

EQ can reduce highs to fool your brain/ear that you are hearing more bass (by removing the highs/mids).

Cloth suspensions (shades of Edgar Villcher) and heavier cones make for lowering f1 resonance but it doesn't make up for moving air.

Speakers have a free air resonnce which changes with the cavity (cabinet) resonance, but small speakers move very little air. Since few have room for a 30 foot air column, enlosure resonances are brought into play - especially with sub woofers.

Ever wonder WHY your voice sounds deeper in a shower? (It really isn't).

Theaters used multiple 15" heavy speakers with folded Megaphones (horns) for bass. Early Audiophiles bought $300 18" speakers, and good/deep bass sub-woofers run $500-$1000.

 

 

Don Gibson .............. ________ _______ I I__()____||__| ||||| I / I ((|__|----------| | |||||||||| I ______ I // o--O O O O-----o o OO-------OO ###########################

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