[Jimster480]

That was my feeling there should be no difference on high gain if it was just a line out.

If it's a fixed line out then probably not.

 

[TwelveTrains]

That was my feeling there should be no difference on high gain if it was just a line out.

From looking at the model online, I'm not sure if there is a line-out.

 

[chihwahli]

High gain was set, because I was switching between valhalla and E5 to hear differences. Indeed, for line out the high gain has no influence. High gain is only for the 2 headphone jack output.
 
Before I used the Valhalla 2, I had to set my software volume settings low and DAC high to suppress the noise. That's why I used such weird volume settings as you have noticed.

 

[chihwahli]

Since I turned down the volume,  the tubes don't get that warm. This will make my tubes last longer. The sounds seem to be the same. Awesome! Thank you for the tip to turn DAC volume to max and Tube volume down (about 27%)

 

[Jimster480]

  Since I turned down the volume,  the tubes don't get that warm. This will make my tubes last longer. The sounds seem to be the same. Awesome! Thank you for the tip to turn DAC volume to max and Tube volume down (about 27%)

No problem!
 
The DAC at the max setting will give you slightly better sound quality anyway!