[linux-audio-user] OT: more about (laptop) hum

[Malte Steiner]

On my recent Linux Asus laptop I have some problems with noise. One 
solution which always work is to play from batterys but I think that 
killed one performance at Piksel where Asus seems to decide to lower the 
USB voltage during a set and renderd my P5 Glove suddenly useless.
Its differs from location to location and I passed some gigs plugged :) 
while I remember a gig in Berlin where the hum was an anoying high 
pitched tone which was transmitted over the buildin soundcard real loud 
but also over a RME PCMCIA Multiface.
Today I had some time to research and rememberd that the RME and my 
mixing desk has balanced plugs which I never used that way, I have to 
confess. I was always happy with unbalanced cables and think I have 
never problems with an old Powerbook TI with which I did lot of 
recording (thats not praising Apple equipment, a Quicksilver G4 Tower 
gives a hell of noise out of the builtin soundcard, you can heare every 
byte which is shifted around).
Anyway I found only 1 'balanced' cable in my arsenal which I seldom use 
('stubid stereo cable, what can I use it for') and voila, humming 
reduced to 98% I would say. There is still a tiny silent high pitch 
sound, I have to crank up all possible volumefaders to even notice, a 
good way to ruin speakers and ears btw., by accidently triggering a 
sound :).
I compared it with noise from other, none digital equipment and its in a 
good league so I am happy for now, except that I now want 
stupid-stereo-cables-no-one-can-use, to go balanced, but unfortunally my 
bankaccount is not balanced either so it has to wait.

Cheers,

Malte
-- 
Malte Steiner
media art + development
-www.block4.com-