Question about sound levels

[jsteinhauer]

When setting up surround speakers, you adjust the level of each speaker independently of the master level, in such a way to optimize the sound at the listening position. Does it matter what you have these relative levels set at, so long as they match the position, or will you have a different result with say, your speakers all set at -5 to -10dB and turning your master volume up to 29dB versus having them all set at +5 to +10dB and only turning you master volume up to say 9 or 19dB?