Originally Posted by
technobear
A 10% higher voltage will give 21% higher power - that's a fifth more and easily audible!
(Power = volts x amps, for a fixed impedance if volts goes up 10% then current goes up 10% and therefore power goes up 21% since 1.1 x 1.1 = 1.21)
As I said, I didn't look at the maths. From memory (40 year old memory)
For watts 10 log (P1/P2) [The 10 is there because we want the answer in deci Bels, not Bels]
For volts 20 log (V1/V2) [The 2 is there because of Technobear's point.]
gives the dB between the two signals
20 log (2.0/1.8)
according to Google calculator this is
20 log(2.0 / 1.8) = 0.915149811 dB
ie about the limit of human discernment.
This site seems to confirm my memory
http://www.astralsound.com/the_decibel.htm
Anyone more knowledgeable want to chip in?
Last edited by Labarum; 10-10-2009 at 11:27.
Brian
In Southampton: Raspberry Pi 4 running PiCorePlayer, Beresford Caiman SEG, Quad 77 Int Amp and CD Player, AVI Neutron 4, Sennheiser HD25 headphones.
In Nicosia: Small Format HTPC, Beresford 7520 ,Quad 405-2, Quart 980s German Tower Loudspeakers.
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