In Redclound I added some code to help with lower level detail. The problem was that things would go south when the volume got too high. So when the volume of the music after the volume control got too high I disabled the new code and then you were essentially running Huron. (When thing quieted down it went back to the new code in Redcloud.) That change happened at about volume of 84.
The Windom release used some features of the DS Sr hardware that among other things increased that number to 92.
Once again use what ever volumes on your preamp and the DS that sound best to you, But you might want to try 92 on the DS and use the preamp volume while listening for just a little. Then go to whatever pattern of volume on the DS and/or volume on the preamp you like. If you always play quieter music or dynamic music which is mostly quiet the volume can be higher on the DS if you wish. Some don’t find all of this “nonsense” to be worth it at all and keep their DS at, say, 100.