ESU Loksound and 3 rail?

[fishbelly]

I do not model O-Scale, but am getting more interested in it.

My first question here is. Will the loksound decoders work with 3-rail O-Scale?

I am not impressed with the Lionel TMCC sound. If I make the move to O-Scale, I would like to use Loksound.

[tillamook]

If I would make the Jump to O scale, it would definitely not be 3 rail.

More on topic: ESU makes decoders for O scale. Like the micro for N scale, there’s the L for O scale and XL for even larger gauges.

[big train james]

Hi Brian ( fishbelly ),
Yes, Loksound, or any other decoder for that matter, will work with 3 rail track. Likewise, traditional 3 rail control systems like DCS, TMCC, or Lionel Legacy will work with 2 rail track. This is because the control system in any case only cares that it gets power and a signal, without regard to number of rails.

The number of rails really only controls how the power and signal arrive at the locomotive. In 3 rail, both outer rails are the same polarity, while the middle rail is the opposite polarity. I believe the middle is the hot, and the outer rails are the neutrals? Not sure on that since I'm a 2 rail guy and I've never needed to know.   Anyway, the only real advantage to 3 rail track, which is pretty negligible in the era of modern electronics, is that it simplifies the wiring of reverse loops and wyes, and also the wiring for the sensor tracks to activate animated O gauge accessories. Most 2 railers (O scale) don't care about animated accessories, and we use dcc accessories to handle the reverse loop situation. 3 railers (O gauge) usually still do care about the accessories, and they still don't need to do anything to address the reverse loops.

In short, using dcc and Loksound with 3 rail track would be exactly as simple as using dcc and Loksound with 2 rail track.  You still have two leads (I guess you could argue 2½ maybe) from the power supply to the tracks, and you still have two wires from each truck to the decoder.

The only issue I can think of, and I haven't heard much about it lately, is how most modern (production, not era) O scale/gauge locos utilize two motors, which can confuse a decoder if using back EMF functionality.  The decoder would receive feedback from two sources, and then have to decide which feedback to respond to.  Maybe this has been sorted out on the newer decoders, like I said I haven't heard much about it in a while.  

A lot of 2 railers, myself included, are moving to using Loksound decoders and Tang Band speakers, enough so that ESU has started stocking the Tang Band speaker modules themselves.  There used to be a lot of discussion on the old Appalachian & Ohio forum, but they moved to a new software and most of the old stuff didn't get archived.  But here's at least one discussion to check out.  Also here are several youtube links where guys are using Loksound decoders, usually with the Tang Band speakers.

Pete M./GP9um - Loksound, Tang Band 1931S speaker modules, except the f7b has a really big 1942S module in it

Serge Lebel - Loksound in an Atlas loco, but I don't think he's using the Tang Band speaker module

Not judging in any way, I'm firm believer in doing the hobby however you like, but I too am curious as to the combination of 3 rail and dcc.  It's not a step that modelers moving up from HO to O normally make.  They either want the same type of accuracy they had in HO scale, or they want to take advantage of the "play" factor offered by 3 rail trains.  

Anyway, let me know if you have any other questions, and I will do my best to answer them.

Jim

[edwardsutorik]

If you have two motors in a locomotive, you could put in two decoders, one for each. Then back-EMF is taken care of.


Ed

[big train james]

Hi Ed,
In theory, sure you could use two decoders.  I suspect however, that in practice it doesn't make much sense.  It would be a much better idea to just have a single motor per locomotive for the majority of models, instead of the other way around.  Like they've had in HO for a million years or so.  But the two motor arrangement leaves plenty of room in between for large proprietary electronics boards, and also for the smoke unit.  And since the 3 rail market largely drives product development and offerings (it's currently a bigger segment of O than 2 rail or p48) from mass producers like Atlas, Lionel, and MTH, then the 3 rail oriented components must be accommodated.

An outlier of sorts is the 3rd Rail division of Sunset Models.  Despite the name, they do both 2 rail and 3 rail.  They've recently begun importing short-ish runs of injection molded locomotive models, with single motor drives and without smoke units.  They originally used QSI for 2 rail dcc, but I believe they have made the switch finally to ESU.  They still use TMCC for 3 rail models.

I should look into the progress on motor control on the latest decoders, at least to satisfy my curiosity.  It would be interesting to see if things have advanced.  Come to think of it, isn't there a recent Kato model that has truck mounted motors, and therefor two per locomotive.  And imagine if the dream of axle hung traction motors ever came to mass market fruition.  It's hard enough to deal with the noise and gear reduction in that scenario, motor control for four or six motors might be a challenge.  All presuming that one is utilizing bemf in the first place of course.

Jim

[edwardsutorik]

Jim,

I will disagree, and assert that it does make sense to use a decoder for each motor. Sadly, I have zero experience in the matter. But it would be my go-to solution. I surely would not replace a two-motor drive with a single motor setup because of concerns about the decoders.

Your comment about axle hung motors is interesting. A few years ago, Whats-is-name demonstrated HO axle hung motors. I thought they were WAY noisy. In practice, might be different. Sound might cover up the gear noise. Especially if you're running sound-DCC. But, yes, it's an interesting point to posit 4 motors (or six) in a Proper Locomotive. With a decoder for each motor??

IF. IF. IF..... The idea took off, I can imagine a "master" decoder running 4 to 6 sub-decoders for the individual motors. It actually looks like a super simple problem to solve. Might even throw in 8 sub-decoders for the Centennial crowd.


Ed

[big train james]

Hi Ed,
While put forth in the context of dcc use in O scale, the "single motor per locomotive" thing is actually a bigger picture issue.  There are at least three significant issues with two motor designs, if the bemf issue is truly a problem.

There's poor slow speed loco performance, as there's very little flywheel mass and for whatever reason the gear reduction isn't effective for smooth starts.  That may also be a cheap motor issue, but it's more typical to see the blame assessed to the gear train.  Some of this can be mitigated with the electronics, but it's an example of using the dcc to make the locomotive run okay, instead of making a loco perform well and then add dcc.

The motor at the front of the locomotive almost always protrudes into the cab area, sometimes quite significantly.  The solution is to put a shroud around the motor and hope for the best.  It's not a very good solution.  Certainly, if a modeler had any interest in representing a cab interior, they would be hampered by the presence of the motor.

Then there's the motor control issue already noted above.  All these issues would be solved quite easily by switching to a single motor design, but it's all a matter of priorities.  Two motor design facilitates the other types of features that many people in O gauge want, so it's what the manufacturers provide.

On the topic of axle mounted traction motors, whats-his-name's prototype is exactly what I was thinking of regarding noise.  If the solution to the noise is to mask it with a louder, different noise, then I doubt that would be an effective answer, at least for me.  I enjoy sound more than I expected to, but I prefer it to be subtle rather than overwhelming.  

And finally, back to multiple motors/multiple decoder applications.  I can think of several reasons why I wouldn't want to pursue it.  There's cost, O scale decoders cost a lot,  even for one.  It would still be substantial even if you could downsize to HO decoders to match smaller motors.  Motor cost would increase in the same way as decoder cost.  There's size, you would need a lot of physical volume to accommodate multiple decoders.  Then there's the thing about motor control.  It's common for motors built from the same spec to perform differently.  Unless the motors for any given loco are sorted and tested for compatibility prior to install (that would be a cost thing too), then they ideally would need to be speed matched.  I'm not sure how you would achieve that, on a single chassis.  Maybe with only two motors, the issue is insignificant.  But consider the dream scenario with four or six or eight motors and decoders per locomotive.  It sounds like a lot of overhead.  

I still like the idea of axle hung traction motors, but I'll need to win the lotto so I can throw some money at the problem.  I would want to use some quality motors, I'd probably aim for Faulhaber gearhead motors, which would add up pretty quickly.  Then I would need to (hire somebody to) design some new electronics and code.  I think it would work with the master decoder receiving bemf input from the sub-decoders, making decisions about what information it receives, and then tailoring new directions for each decoder in response to match up their performances.  It's not all that complicated of an idea, it's what computers do all the time.  Our cars do that sort of thing with full time all wheel drive and traction/braking control.  It's just not an off-the-shelf solution at this time for model trains yet.  Just need that money to get started.

Jim

[edwardsutorik]

Jim,

For DCC, flywheels are not needed. If it's not inconvenient, I remove them. I just did it on a loco--no problems at all.

I agree that quality motors are always better than crap motors. And DCC generally makes motors run better than not-DCC.

In a proper world, DCC is not an excuse to use crap motors and gearing.

I am NOT speaking from experience, but if I had a two motor loco, I'd put in two decoders. Actually, I do have such a project in mind, but it's WAY far away.

I wouldn't bother with axle-hung motors. I just don't see the benefit, aside from maybe fully detailing the guts. For your info, Rail Flyer Models was putting together such a thing in HO. I saw the motor/drive:




Very clever, but very why-bother.


Ed

[big train james]

I presumed that Railflyer was Whats-his-name. That's the example I was thinking of anyway.

I tend to agree, the axle hung motor solution isn't necessary for 99% of applications. Maybe only 95%? It would be useful in smaller locos like switchers, and clearly it would be useful for things like RDC's and traction models. But at least for now, I don't think the return on investment warrants the effort.

Oh yeah, there's also that thing about a combination of smaller motors generally being less efficient than one large motor, all other things being equal. But I don't think we need to try to convince ourselves any further.

By the way, there is a company out of the Chicago area, Midwestern Model Works, that has gotten involved in importing O scale brass models. He is offering a Premium or Platinum or Epic or whatever super model of the sd40-2 (I think maybe a premium dda40x too, can't remember for sure anymore) with full long hood interior, apparently with a single motor drive. Even as compulsive as I can be, it isn't for me. I can appreciate it, I'm definitely a model-things-whether-I-can-see-them-or-not-because-I-know-it's-there type of person, but it's a length I just won't go to.

Jim

[fishbelly]

Jim,

Thanks. Or rather thanks a lot! for posting the two links. WOW!!!!!!!!!!!!!!!!!! You can really hear the bass in the sound. I could feel the thump of the motor. Nothing we will ever get from HO scale and this is really making me rethink the scale I am in. I love the deep sound you can achieve with the larger speakers in O-Scale.

[edwardsutorik]

The sound from my HO Athearn GP9's is quite good. Not as good as the first link, of course. But definitely an improvement from previous versions.

Yeah, modeling things that can't be seen isn't me, either. I've even been known to skimp on underbody detail, which clearly DOES show in a good and proper wreck.

I also tend to put my "keep alive"s in the (now empty) bathrooms of passenger cars. "Conductor! There's a big ugly THING in the bathroom. Get it out, this INSTANT!!"


Ed

[severn]

Mth uses painted black and white stripes on one motor's flywheel with some kind of ir or similar sensor to ascertain speed. Lionel uses similar but magnetic or other options to get around the mth patent in this area. The dcc approach uses so called "back emf" (bemf) which is residual power from a spinning DC motor to calculate speed using a well known relationship to it, as has previously been determined by others.

Mth and Lionel control systems are compatible with each other in the sense that they don't interfere with each other. The Lionel systems (yes there are 2) use rf. One is legacy, product of the same name and this is on all their most expensive products. The other is based on Bluetooth.

Mth is an on the track approach more similar in concept to dcc but has a proprietary implementation. ("Spread spectrum" )

I believe at least some mth products support dcc with a switch setting ... More towards the 2 rail market. I can't say how good or bad it is etc... Exactly which ones etc...

So should you aquire one of these engines I believe you can certainly replace it's proprietary control with dcc and there's a few dcc boards out there for the larger voltages 18-? V and bigger current draws of o gauge...