DCC and sound

[Don Gibson]

Is SOUND baffling? A Primer.

HERE's a simple test for you Broadway owners on the subject of 'Baffling'.

1. STEAM: Remove the tender superstructure (it's a friction fit) Run the engine around 9 volts so it 'chuff's and runs slow.
2. with the tender top in your hand place it loosley on the top of the chassis. Now remove it..... same engine, same speaker, same amplification.

WHAT you are hearing is the 'Baffling' - or separation of back wave from front wave.

[mcouvillion]

I've placed sound decoders in several of my engines/lashups: 1) a Soundtraxx DSX decoder in the dummy of an ABA Alco lashup, with two baffled 1" diameter round speakers in the dummy and one each in the powered units, 2) a single 1/2" speaker recessed into the weight of an Atlas RSD-4 under the fan shroud that was drilled out to "release" the sound from a DSX Soundtraxx decoder, 3) a DSD-090LC Soundtraxx in an Athearn Trainmaster with a 3/4" x 1.5" baffled speaker (this engine also has the new pinhole color video camera under the hood!). The sound from the baffled speaker installations is broad-spectrum and the volume is adjustable. The un-baffled speaker installation is imperceptible with any other background noise (even at maximum CV values) and I have been disappointed by its performance (though there is absolutely no place the put a baffle in the engine - I almost didn't get the decoder and speaker to fit).

Sound adds a lot, but if too loud is very annoying. The crew I run trains with has decided to reduce the CV setting on sound decoders from the default (I remember it being about 75% of the range) to about 20 - 25% of the range. This has made a huge difference. The sounds are still noticeable, but don't carry "100 scale miles" as mentioned above. We have begun trying to incorporate the whistle signalling into our operating sessions, and try to ring the bell continuously while moving within yard limits.

As for letting the sound escape out the top or from the bottom of the engine, I don't think it makes any difference three feet away from the loco. You can't tell the difference if the decoder and (baffled) speaker are installed properly

We used the boxcar method when sound decoders first came out, since we were skeptical and price -conscious. All of the engines for our regular operating sessions now have sound and our individual favorites do too! It has added a lot of realism and enjoyment to operations.

[Don Gibson]

QUOTE: "I mount the speaker in the roof facing up, and the sound is pretty good, I think.

JOE: You are correct - as long as there is a 'hole' for the sound to squeeze through. - Think of a 'shower head' with water. - Don.

Reason: By Sealing off the back wave from the front, the whole body becomes a baffle

[jfugate]

QUOTE: Originally posted by darth9x9

I really liked sound at first but I visit a large layout regularly that has a dozen or more locos with sound (out of over 50 on the layout). I love the F8 feature...ie mute button! There is just too much sound to be appreciated.

One feature I really like in the Soundtraxx decoders is the timeout feature. If the loco is no longer assigned to a throttle, you can set it to automatically mute after a set length of time. I have mine set at 60 seconds.

So once you pull the loco lashup in to the yard and tie up, 60 seconds later, the lashup goes silent. No muss, no fuss, it just does it on its own once you deselect it's address so the decoder is no longer receiving any commands.

[AntonioFP45]

Thanks for the input guys!

JFugate, you gave me a good option to think about. I'm going to wind up having two E7 B units and at least one dummy FP45. Very generous amounts of space. Will be taking advantage of it! Since motor control won't be an issue I'm assuming I'll be able to use the Soundtraxx DSX series decoders.

I am definetly staying away from the LC series. I know that even at low volume a decoder with a more powerful amplifier will give out more dynamic sound as is the case when comparing the DSX decoders with the LC. I don't mind saving and budgeting a few extra dollars for quality sound. If one's getting sound, might as well get the good stuff!

Cheers and Thanks!

[darth9x9]

I really liked sound at first but I visit a large layout regularly that has a dozen or more locos with sound (out of over 50 on the layout). I love the F8 feature...ie mute button! There is just too much sound to be appreciated.

[jfugate]

QUOTE: Originally posted by AntonioFP45

... JFugate,

Scenario: On HO E units, F units and Cowled locos (F40, FP45) wouldn't it be better to ... install the speakers on the ceiling so that the sound will come from the top area of the locomotives instead of the bottom? Do you think it would be louder and more dynamic?

I've looked inside the bodies of my P2K E units and my Athearn FP45s and there does seem to be a reasonable amount of space for 1 or 2 small speakers on the ceiling. I'm just a DCC newbie though. Any thoughts? [:D][:p]

You are right about the space issue in powered locomotives, although with some creativity and a willingness to cut and trim the loco weight a bit, you can get a decent speaker in a powered unit usually. Smaller units like switchers are the toughest.

I prefer to avoid all the cramming by just installing the sound in dummy unit and then I can move the sound around between lashups as well. The larger the speaker, the better the sound, so a dummy unit gives you lots of space to work with. I mount the speaker in the roof facing up, and the sound is pretty good, I think.

Haven't tried multiple speakers, but I can see how it could improve the sound. But even one speaker and an LC decoder with sound is enough to become adicting (dkelly, look out ... )

[AntonioFP45]

QUOTE: Originally posted by robengland

No one mentions a problem I had with the LC decoders, one steam and one diesel. In both locos (both Athearns) the LC decoder produced enough buzzing in the motor to almost drown out the sound! When i wired in a separate decoder for the motor, problem fixed. Yes I did try tuning the pulse-width CV, didn't seem to have much effect.
Personally i will never buy an LC again. Soundtraxx for sound, anyone else for motor control

Robengland,

I know that you're looking forward to the Surroundtraxx, but have you tried Soundtraxx's DSX decoders? From what I've read the sound is more powerful and of course you can install whatever motor decoder that works (TCS, Digitrax, etc)

[robengland]

they don't come anywhere near close. see other threads. they aren't polyphonic, and have limited sound options.

you gets what you pays for

[Anonymous]

Wasn't MRC supposed to be releasing a new line of sound decoders ? Anybody have any info on them ? They're prices are/were , half of a soundtrax decoder. It would be nice if the new ones from MRC could get close to the BLI / Soundtrax quality .

[robengland]

No one mentions a problem I had with the LC decoders, one steam and one diesel. In both locos (both Athearns) the LC decoder produced enough buzzing in the motor to almost drown out the sound! When i wired in a separate decoder for the motor, problem fixed.
Yes I did try tuning the pulse-width CV, didn't seem to have much effect.

personally i will never buy an LC again. Soundtraxx for sound, anyone else for motor control

[johncolley]

It would be interesting to see a comparison chart of sound levels, for instance: On my pair of BLI E-7's depending on the size of the room and hardness of the surfaces (drywall or fully scenic'd with brush and trees) What scale level of sound would you hear at 100 ft, 1,000 ft.? In a hard surfaced small room I run about level 9 or 10 in analog. It will be interesting to hear it next month when I get onto DCC.

[Anonymous]

I have added Soundtraxx DSD-LC sound decoders to a Bachmann Spectrum 2-8-0 with its on-board speaker, and to LL P2K 0-6-0 and 0-8-0 steamers, using a medium size oval speaker firing up through the coal load. I think they sound really nice, although I've never heard a DSD equipped loco for comparison.

Same decoder series are in a BL-2 firing up through the fan grilles, four Atlas RS-3s
mounted on cut down weights, and a Kato RS-2 with one weight removed. None of the speakers have baffles since the shell is such a tight fit for the oval speaker I used. The shell pretty much acts as a baffle. Sealing the speaker to the Atlas weights (holes drilled in them to let the sound out) separates the forward pulse from the rear pulse.

Not having the baffles doesn't seem to make any difference in any of the Diesels. They sound good to my ear, aren't so loud as be annoying after a while of running, and the sound level for bell, horn and engine can be raised or lowered independently. I set them so I can just about hear them from the far side of the layout.

[tomwatkins]

Sound in very addictive. It really adds a lot to the operating experience. After running a sound equiped loco, either BLI or Soundtraxx equipped, a non sound equipped loco isn't nearly as much fun. I agree with the comments on speaker location and should have mentioned it in my earlier post. In a steam tender I mount the speaker under the coal load, facing up and drill holes through the load so as not to muffle the sound. The coal load itself is built up on a piece of sheet styrene so the load can be removed if needed. In my diesels I mount the speaker in an unpowered B unit or second unit in a permanent lash up with the speaker facing down towards the fuel tank. Holes are drilled in the bottom of the tank, once again so as to not muffle the sound.
Hope this helps,
Tom Watkins

[Don Gibson]

Boys:

The sound goes out the Bottom (and also the top) any how. The rear of the speaker reproduces most of what comes out the front ( unless sealed off) but in reverse phase. When the front 'pushes' the back is 'pulling' ,and vice versa. The waves at the sides cancell - that's why you need to separate or 'baffle' them..

Opening in the top are ideal. The front wave is pushed through the grills, and the back wave sends sound out the bottom and bouces.. The sides of the body separate the two forming a baffle.

Lining a tender with lead does not enhance the sound, just dampens any vibrations if you have any, by preventing flexing of the body

The bigger the speaker the more air it can push, and the more back to front separation the more frequencies it can produce. 1 watt can produce a lot of sound.

Since our ears hear sound in motion It's the speaker that moves the air, and the amount of air that reache us determines loudness. Considering the size of HO, it's the size of the speaker that is the biggest limitation.

A speaker in a flat infinite baffle mounting can product good sound. Example: a Baggage car with a speaker sealed over the doorway firing forward. The back wave is separated off by the whole length of the car. (You will have to connect with two wires to the sound source}.
Another is a stock car with a 1" speaker mounted to a baffle glued to one side. Sound comes out both sides and makes no difference which way it is facing. Both excellent.

[cacole]

AntonioFP45,

Yes, if your locomotives have see-through fans on the roofs, mounting the speakers there would probably give you good sound output by mounting the speakers directly under them. I didn't do that on my Proto 2000 units because I didn't want to have any type of wiring restricting removal of the shell. Since the bottom of the chassis already had fairly large openings on the dummy units, it was easier to mount the speakers there and let the sound go out the bottom.

[AntonioFP45]

Understandable DKelly,

But if you do check it out, it will really give you something to look forward to! Hope you get out of debt soon as I know it's frustrating. You sound like your tenacious and will pull through! [C):-)][tup]

Cacole, JFugate,

Scenario: On HO E units, F units and Cowled locos (F40, FP45) wouldn't it be better to have "See Thru" radiator fans on the roofs, "See Thru" grills on the sides. Then, with baffling, install the speakers on the ceiling so that the sound will come from the top area of the locomotives instead of the bottom? Do you think it would be louder and more dynamic?

I've looked inside the bodies of my P2K E units and my Athearn FP45s and there does seem to be a reasonable amount of space for 1 or 2 small speakers on the ceiling. I'm just a DCC newbie though. Any thoughts? [:D][:p]

[Anonymous]

Antonio,

I've avoided that website like big time. Seriously. I remember back in high school (1981) when my dad and I visited a club open house. We were touring the layout when I thought I heard something. My dad and I looked at each other . .. he had heard it too! There was an ABA consit of cab units moving a freight and, yeah, it sounded very real! I forget what system it was. We followed that train around the club I'm sure with bugged eyed wonderment. I can only imagine what the samples on the Soundtraxx website must be like after 20 years of technical progress, digital sampling etc etc!! Let me pay off some debts from my divorce. Then I'll take all the knowledge I've learned here, give Tony's a few calls, choose my DCC system and then . . . . .SOUND!!

[cacole]

I have had experience with the original SoundTraxx DSD 150 and several versions of the DSD LC, as well as two Broadway Limited and one Lionel HO scale locomotive with the QSI systems. Someone asked for a comparison. The DSD 150, no longer produced, has enough power output to drive 2 or 3 speakers, and the LC decoders will only drive one speaker. The new SoundTraxx Tsunami, not yet released, is supposed to be equivalent to the old DSD 150 in power output, meaning it should be able to power 2 or 3 speakers. All of the QSI systems I have use two speakers.

I have installed sound in only one diesel lashup, a Proto 2000 Illinois Central A-B-B-A E-7 set that I use to pull a 12 car City of New Orleans passenger set. For this, I used two DSD 150s and 6 oval speakers with baffles that I purchased from Tony's Train Exchange. The B units are dummys with the decoders and two speakers in the floor of each, and there is a third speaker in the rear of each A unit. Even with this much power, the volume is not as loud as a QSI system, but the sound is excellent with multiple speakers.

I haved installed LC sound decoders into Bachmann Spectrum 2-8-0, 2-10-0, Light Mountain, Heavy Mountain, and Shay locomotives. The key to good sound in these locomotives is the speaker. If you get a good 1" round or oval speaker with an adequate baffle, the LC decoders sound acceptable, but not as good as the DSD 150. The LC units do not have enough power to drive multiple speakers. Because of size restrictions, not even a 1" speaker could go into the Bachmann Spectrum Shay, and SoundTraxx provides an even smaller speaker for this locomotive. There's no room for any type of baffle, so sound is very weak.

The two Broadway Limited and Lionel Challenger with QSI sound systems all use two oval speakers mounted in the floor of the tenders, and utilize the tender shell as their baffle. The QSI systems provide higher power output than SoundTraxx decoders and the quality of sound is much better.

In order to run SoundTraxx and QSI systems together, the volume has to be turned down on the QSI systems or they completely drown out the SoundTraxx LC systems.

One member of our club has MRC sound systems. My opinion: Save your money and get a REAL sound decoder. You have extremely limited options with MRC sounds compared to SoundTraxx or QSI. For example, one function blows a set duration short whistle or horn blast, and another blows a set duration long whistle or horn blast, and these cannot be changed in any way. SoundTraxx and QSI sound their whistle or horn as long as you hold down the function key, so you can determine for yourself how long the sound will be on.

[AntonioFP45]

DKelly,

Have you gone to www.Soundtraxx.com and checked out the sound samples?? (Click on the Soundtraxx DCC box first and the "Samples" box will open up.) [:D]

Originally I was skeptical about sound equipped locomotives, until I checked out the "Sound Samples" on Soundtraxx's web site back in 2002. My eyes bugged out and my mouth went "GA-GA!" [:P][:P][:D][(-D][swg][tup]

As I've stated many times teen modelers like me back in the late 70s were wishing that someone could produce HO or N engines equipped with accurate sound! [sigh][:)]

So "Budget" for it and look forward to blowing that K5 horn on a diesel or making your steamers chuff!

[Anonymous]

OK. You guys have confirmed my worse fears. This sound thing is addictive. I don't see any warnings on the advertisements, but I've always thought this. Not having even gone to DCC yet I avoid sound equipped engine demo's and internet samples like the plague. I'm afraid that once I hear it, I'll skip a mortgage payment and do the DCC/Sound thing for all my stuff, and that wouldn't do. Thanks for the warning!!

I've stopped wishing for the topic thread "DCC and Sound Are a Waste" with millions of posters in agreement.

[AntonioFP45]

Rexhea, thanks!

I would probably use an LC type decoder in a switcher, such as an Atlas EMD SW unit. I plan on installing the Tsunami only in my passenger and freight "Road Engines" since these are what I enjoy seeing in action. The sound of EMD's 645 turbocharged "whine" and the "Chugging" of GE U-Boats were always thrills for me as a teen.

Joe,

Appreciate you sharing the info on which decoders you use. Great news on your Volume 3!!

Have you already produced it or are you in the process? I'm wondering since the Tsunami is due out next month and if you were planning on purchasing the decoder.

One thing you could do: Since you've already met, ask Nancy from Soundtraxx if they would allow you to become a "product tester" for the Tsunami decoder. From what I've been told, this happens a lot in the computer and electronics industry.

Either way, I will plan to purchase the video. It's very helpful when there are live action pictures to go with book info and computer images.

Thanks!

[jrbernier]

I have a pair of BLI heavy mikes, and a pair of Spectrum 2-8-0's with the Soundtraxx units in the tender. The BLI units have better sound, but all need to have the volume turned down when you are running more than one engine on the layout. I like to adjust the sound to the point that it is just above the 'background sound' level. The Soundtraxx B280LC units can be improved by drilling small holes in the tender coal load(hardly show) and adding some foam to the back of the tender - the sound does not bounce around(that 'tin' sound') and is directed out the coal pile.

Jim Bernier

[jfugate]

Antonio:

I have used both Soundtrax DSX and DSD decoders, and I am currently using DSD LC decoders for sound. I put one dummy unit in a lashup with the sound in it. I plan to install just one sound unit per lashup. I have 65 locos for the layout, but only about 20 lashups.

I use DSD LC decoders because they are cheaper than DSX decoders and it's easier to program a DSD decoder. I have found DSX decoder programming to be kind of quirky because it expects to have another decoder connected to do motor things, and the programming got to be confusing when there is NO motor decoder attached but it's expecting one.

Of course, switchers will have sound in them, but they will be the exception.

I find the LC decoder sound to be acceptable. It's not as nice as the full blown sound decoders, but pretty good. I don't need coupler clank, for example. The LC decoder sound can be made to rachet up with the throttle or you can have a function key to change the throttle "notch". This way you can have a lashup in run 8 but just crawling along if you want.

I plan to spend some time discussing and demoing DCC sound in volume 3 of the Siskiyou Line series on Electrical and Control, due out next spring. I touched on it a bit in my DCC clinic, also available on video (see: http://model-trains-video.com ).

Doing loco lighting and sound with DCC are the two topic areas that are seldom discussed. I hope to rectify that in my upcoming video by showing you demonstrations of what I have done, show you my boo-boos, etc.

[simon1966]

I have a pair of BLI mikes and am awaiting the arrival of a BLI E7. My only comment is that it can get a little noisy in the train room if we dont drop the volume down on the locomotives. I think I might patent the concept of "scale sound". This would automatically compensate the volume of a locomotive so that the sound level would be approriate for scale distance! On my layout, the coal mine is supposed to be 100 odd miles from the powerstation. However, I can hear the mikado accross the room a supposed 100 miles away. This is clearly not realistic![:D] I should be able to screw up sound equipped locomotive manufacturers for years by getting a patent to cover this idea that manages to encompass volume control.[}:)]

[rexhea]

Joe

I know exactly what you mean. I have a P2k GP7 that is the smoothest runner I have, but without sound. When I start it up, after running loco's with sound, it's almost like its not real or somethings not working. Just BLAH!
Because of that I am trying to go with sound in everything. I even installed a large oval and a round speaker in a box car to connect to those loco's that are too small for a reasonable size speaker. I plan to rig more using the Soundtraxx DSX onboard decoder. So they drag a box car around all the time. Heck! It's worth it.

Antonio,

IMHO: If your looking for realistic sound patterns, don't buy the Soundtraxx LC. It is ok for the sake of having fair sound and it is cheaper, but it doesn't have the power or as many varied sounds and functions. Hopefully, the Tsunami will be out soon and that one will be the King of them all.

REX [:)]

[AntonioFP45]

Joe,

Hope you don't mind me taking advantage of your posted question:

Are you using Soundtraxx decoders? If so, what types do you have? (DSX, DSD, LC,etc.) Or are you using MRCs?

If you have various types, how do they compare with one another as far as quality, dynamics, reliability?

I'm asking as while there a various sound systems out there, few modelers that own locomotives with sound have commented on this forum about their own experiences, comparisons, etc. Instead most DCC modelers, including you, have provided very good info on the "DCC" arena (hookup, troubleshooting, CV functions,) but not much on the "Sound" side.

Thanks!

[jfugate]

Although my HO Siskiyou Line layout is set in the 1980s and we run diesels, I can tell you the reaction of my operating crew to sound.

I do not have sound installed in all my locos, but the reaction is the same for whomever gets a lashup with sound.

"You need to put sound in all your locos ... the other locos without sound just seem dead, like there is something wrong with them after I run a lashup with sound".

The point is, sound is addicting! It adds a lot to the operating experience.

[cacole]

Perhaps the demonstration you heard was with the locomotive operating on block DC control and not DCC. The sound effects are quite different when it is running under DCC control. The test track or whatever you heard it on can have an effect, too, if it is just mounted on a piece of wood with no cork roadbed.