Hi Pete
No, not an XL. I've used one of them in a G scale loco, but only V.4 L and Select L in O scale.
What I have now is an Atlas SDP 35 and the rebuilt Weaver GP 38-2 with the adjustable tower. The Weaver runs very smoothly on notch one (you can barely see it moving), but the Atlas is lumpy until about notch 4. Both have Select L decoders. The hum is bearable.
Interesting about the coreless motors. I read somewhere that they don't like PWM power. Maybe I imagined it. 
Cheers
Thanks Max, I've got it now, finally! Re coreless, you're right, we discussed that in your GP38 thread also. Coreless motors have been in European O scale for a long time. They don't like low frequency PWM such as found on early Digitrax and NCE decoders, and tend to overheat or melt. One reason Zimo, Lenz and ESU decoders have much higher frequency PWM is to optimally control coreless motors. Which happens to be a factor in why they don't work a well with "old school" Pittmans and to a lesser extent, somewhat newer Atlas can motors. Sigh.
Like you said it's a sport not a hobby...
Pete
Well, now I don't know what to do between staying with QSI Titan Magnums or trying L Selects or XL's in my O scale steam engines which probably have "recently manufactured Pittman's". Guess this means I'm confused on a higher level which is a form of progress 
.
Please clarify what is meant by an "old Pittman's."
ScottK. While your Atlas O MP 15 has a horizontal drive, not china drives, best I remember it had no low speed hum. Correct? Judging from the pictures looks like a pretty standard can motor. Nothing special. Correct?
I have some engines with QSI Titan Magnums which initially had low speed hum - especially at startup. But, almost all of it was worked out to the point that it was all but gone by carefully setting decoder properties using CV Manager. Are you guys saying that the Loksound series does not offer this type of motor tuning or what?
Good stuff. Thanks, Bill
HI Bill,
I did not notice any hum on my Atlas O MP15 and I have run the loco with the sound muted and still no noticeable hum. These Atlas horizontal drives, like the one on this MP15, use basically the same motor as those used on the dual vertical drive configuration. Also, as another data point, here is a video from Alex K. from DCC Train on Rick Trinkle’s Overland SD70Ace (Pittman Motor equipped) Loksound XL 4.0 installation and a short test run and I don’t hear any hum, Just the sweet sound of that EMD 710 prime mover . The actual demo starts at the 7:35 mark.
Scott K.
Austin, TX
Austin Bill posted:Please clarify what is meant by an "old Pittman's."
Bill, the Pittman motors used in O scale models come in 2 broad types. "Seriously old" ones with regular magnets and "fairly old" ones with Alnico magnets. There are plain bearing and ball bearing versions of both as I understand it. These motors have not been made by Pittman for something like 10-15 years as I recall. This based on a post I read by a proper O scale drive expert (maybe Jay Criswell or Rod Miller?). It went roughly like this: A builder contacted Pittman a few years ago for more of these motors for a run of engines and the Pittman guy wondered why someone would want to order something they hadn't made in many years.
Anyone please chime in if you have actual facts to correct my shaky anecdotage... 
I think these motors were top of their class in their day, but modern can motors and especially coreless motors are way more efficient - a lot more torque for less Amps in a lighter package.
Some of this was covered in Max's excellent Weaver GP38 thread:
https://ogrforum.com/t...first-attempt?page=1
Pete
Pete and Max,
I just "slogged" thru the lengthy GP-38 post. A monument to tenacity with a very good outcome and an interesting learning experience. All I can say is that hum in the earlier video sounds the same as a DC non-decoder engine sitting on a DCC layout as Max more said. Sounded like no decoder or a faulty decoder. Or maybe just bad luck with that particular combination of motor and decoder?
The GP-38 performance in that last video was awesome. Certainly equal to anything I currently have. ScottK ran his L Select equipped engine on my layout and it too had excellent sound and motor control . I can only conclude that we "pay's our money and take's our chances" with each project regardless of what brand decoder we select to combine with what ever brand motor is in the engine -- for starters. Then take it from there.
Thanks, Bill
Austin Bill posted:Pete and Max,
I just "slogged" thru the lengthy GP-38 post.
You might need a little lie down after that!
I learned a lot from that thread. I also thought that buzzing was the "DC loco on DCC" buzz at first, but the I realized the buzz gets higher frequency as the throttle increases, whereas with a DC loco on DCC it gets lower at throttle steps increase. So I did come to think it was the variable frequency PWM that modern "Euro" decoders use to optimize stating and slow running. They start off around 40kHz which is great for coreless motors (and way above human hearing of course) and seem to drop down to try and compensate to control higher current drawing, lower efficiency can motors at start off and low speed. Pittmans with their 8-10A stall current draw seem to be the least good fit with such a motor control approach. Mind you, this is total conjecture on my part as what I know about PWM, VFD, motor power factors etc. can be written on the head of a pin!
Next for me is to try a coreless Pittman replacement with an HO Loksound decoder and I will report back as soon as I get it done. I will use the Finescale 360 tower kit as well on that one.
FWIW currently I am running an HO Loksound Select in a Yoder 44-tonner, and an HO TCSWOW Diesel in an Atlas SW9 and both are excellent at start off and slow running after a simple 1 minute calibration step as described in the manuals. I do also have 2 Atlas China drive GP35s with HO Tsunamis that run OK. No issues under load, but it took a week of evenings messing about with multiple CVs based on 3 different recommendations found online to try and get the slow running nice. And it has never got close to what the TCS and ESUs can do out of the box.
Onwards and upwards...
Pete
Thanks again, all.
Factoring in all I've learned from seeing Scott's engine in person on my layout and then following all of the informative responses to his topic, I've decided to go with the Loksound XL 4.0 for a steam project. Just ordered one from Tony's. The XL will easily fit in the project tender. The selling features for me are: Screw terminals instead of those tiny solder pads, on-board Keep Alive (by any other name) making the price seem more reasonable, two separate audio channels that can be balanced for one speaker in the boiler and one (larger) speaker in the tender to enhance bass response (like with my QSI 6 amp Titan Magnum Q2 and Q3 decoders in steam engines).
I also have two Titan Magnums with the latest Q3 firmware yet to be installed. They are awesome too. And I have been using the QSI Quantum Programmer for years and look forward to learning and using my new ESU Loksound Programmer. Best of both worlds? No wonder, I haven't gotten around to starting scenery on the layout. Oh well, it runs well under NCE DCC control.
Thanks, Bill
I think that's a good decision Bill. Looking forward to the video! I hear that the Q3 firmware is a huge improvement for QSI so I look forward to hearing about that as well.
Pete
rdunniii posted:The new Atlas 2-rail U23Bs come with the adapter for the LokSound decoders installed, including the speaker and lights. As they are DC only there is a plug where the decoder goes but it is a direct physical swap with the retail decoder.
If an adapter for a U23B doesn't work, can you replace it with the loksound select L adapter? Can the loksound select L adapter manage lights to the U23B by itself?
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