When adjusting audio settings your ears are one of the most important tools you have. Adjust the settings until you are happy with the sounds.
George at Soundtraxx has many videos regarding the setup of their decoders and one on the equalizer settings provided the basis for this guide.
I set CV225 = 7 which allows you to customize the equalizer settings. The small speakers in all but the largest of scales cannot reproduce the low frequency sounds faithfully so as you can see, those ranges are at zero to prevent the amplifier from wasting resources that will not be heard.
Here are the settings gleaned from the video. I used these as a basis and you can tweak from there if you like; I am happy with them as they are.
CV226 = 0, CV227 = 0, CV228 = 200, CV229 = 220, CV230 = 175, CV231 = 170, CV232 = 100
Once you are happy with the equalizer settings, lets move on the the reverb/echo settings as these add the finishing touches on the sounds.
I found I liked the sound of CV233 = 4 (Short Echo)
I set the reverb mixer levels as: CV161 = 100 (Airhorn/Whistle), CV162 = 64 (Bell) and CV163 = 96 (Prime Mover/Steam Chuff)
.Everything sounds great, the whistle and bell have a nice delayed echo but the surprise was with the exhaust chuff on the steamer.
I use 28 speed steps and in steps 1 thru about 6, I get an "echo chuff" after each main blast which really sounds great. Above that, the echoes melt away and are not noticeable. On the articulated I left it at the 96 setting speculating that might be the sound of the HP cylinders exhausting into the pipe transferring steam to the LP cylinders. I have never been near an articulated running so I just have to guess but the sound is impressive.
For my Mogul, I reduced the level to 163 = 70 and the effect though reduced is still something I want to keep.
As always, play with the various settings to see the effect and set them to what sounds good to you.