How to keep albums playing at the same volume

The only way to do that is to compress the signal. It's not the peak loudness but the average level if I understand the issue correctly. The problem is that really ruins the music. There are affordable devices that do this but the results are not dramatic.  

There is software that will "normalize" volume to a consistent average and save that info to the file when a disc is ripped or a file is processed. It works without compression, but by raising or lowering the file’s level by a fixed amount depending on the software’s analysis of the file. If you normalize an entire album, you’ll want to have the same volume adjustment done to each track to preserve the feel of the album.

As described above it is easy to do via JRiver software. Likely other ways and just look for volume normalization or similar.