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Hello, I’m in the process of speed stepping a few Athearn genesis series With tsunami sound locomotives to run with other various engines and I find the Athearn run extremely fast. I’ve been able to lower their speeds using various CVs: 66 and 95. They now run at a speed I’m satisfied with but the engine sound still spools up way too fast. I feel like the engine is in run 6 when I’m crawling through the yard.

Is there a way to slow down the increase? I’m using NCE speed steps 1- 28 and find the engine screaming sound by step 12 or so.

I also can’t figure out how to get the JMRI speed tables to work for the tsunami engines. Even when I set the whole table to a value of 0 nothing changes. The only changes in speed stepping are using cv66 and 95.

Thanks
 

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I haven't had a layout in near 8 yrs due to relocating 2 times.
I don't know if this pertains at all: I believe for chuff rate on steam (syncing chuff rate with driver rotation), it was CV 116..
Just for the halibut see if 116 works on diesel engine spooling-up sound rate ..
 

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CVs 66 and 95 are the forward and reverse trims. They are used to fine tune the engine's response once the speed table is set, say if you've got it matched pretty closely to another engine, but you need to just tweak it a bit, but you don't want to go through and individually tweak all 28 CVs in the curve. CVs 67-94 are the ones that actually set how fast the engine runs at each speed step. It's best to leave CVs 66 and 95 set at 128 until you've set your actual speed curve.

I gather from your post that you have a JMRI set up. in order to use manually programmed values for CVs 67-94, there's a couple steps you need to do first. At the top of the "Speed Table" tab, there is an option that says "Use Speed Table". Click it. Below that is a drop-down menu that says "Speed Table Selection". This lets you choose from various straight, exponential, and logarithmic speed curves (I've never had much luck with those), as well as the option for the fully user defined speed table. That's what I usually use. That's the one that allows you to individually program CVs 67-94 and have the engine run according to those settings. Obviously, if you want to use the user defined speed table, you'll need to select this option in the drop down menu. Then use the sliders to set the values for CVs 67-94, and click "write changes on sheet".

And as the other fellow said, CV 116 controls the number of steps between prime mover notches, as well as things like the interlock, manual notching, and dynamic brake sounds (for instance, it controls whether the prime mover notches to notch 4 when the dynamics engage, as many EMDs do).
 
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