10 Nov
2006
10 Nov
'06
2:24 p.m.
Thanks, Hartmut!
Actually I was able to get rid of one kind of hum with my forced ground
remover.
Quite possible that there's lamp dimmers somewhere near every single
place I start making music, but I found that the hum originates
somewhere in my computer is a more credible explanation, especially
since I can hear it with bare ears; a soft noise, almost like hard drive
spinup noise, but a bit louder and continuous. Only comes up when using
realtime live audio.
I had a quite similar Problem (that ceased after i
stop using a
Lamp-dimmer in the room next door) and i am sure to call it
"network-hum" instead of "jack-hum". Little poor innocent jack is
just
software - has no capabilities to fetch stuff from the real world, that
is not *there* in the first place ;-)
LOL... agreed on Jack, I guess... Unless, of course, the hum really does
originate inside the computer, in which case 'CPU kernel controlled by
jack hum' would be probably most accurate.
some 20 Years of fightig (unwanted) noise in
audioelectronics give me
the strong feel, that your problem is caused by
hardware/cabeling/powersupply. You have mentioned, that you have a
fw-sounddevice and that the hum unfolds, as you start up jackd. Jackd
fetches the stream from the fw-device and if it causes humming jackd
naively thinks, you want everything you precious soundcard generates ;-)
here are some suspects:
power-supply of the device: try changing its connection to the ac-net
(vulgo: connect it to another powerline - preferably the same, you have
your Computer connected to, rule of thumb: all devices should share the
same fuse.)
Already done... no noticable effect.
cabeling of the stuff, that is connected to the
device:
Microphone-cables should be hi-class, adapters shall be at the same fuse
(see above) if you need phantom-power, fetch it from a mixer/preamp,
that gets its current from the same etc...
Done. The hum is also there when there is no microphone connected.
Neon-lights, dimmers, everything that needs a
power-transformator. It
can be the cute lights for the aquarium in the room next door... those
produce electromagnetic waves that can pollute badly grounded/shielded
cables, device-hulls etc etc
I do suspect the noise originates inside the computer... Since I can
hear it with bare ears and it just gets amplified by whatever sound card
I happen to be using.
If you play Guitars, Synths etc hardwired (eg. with an
electric
connection to the network/system), try to use direct-injection-boxes.
network means: everything that has an electrical connection to whatever
device you use, including stuff like modems, ethernet AND ac-plugs,
electronical instruments, Lamps, hair-dryers, chainsaws, peripherals
like printers, scanners, cameras etc. connected via USB, Firewire,
ethernet, guitarcables, ac-adapters - you name it.
K guess I'll try some more... But I still think jack is making my
computer hum, if only because of the stress the guy is putting on my
museal notebook computer created by the ancient Romans in 200 B.C. The
front plaque reads 'Dellus' and it runs a kernel called 'Linus'. The
vendor assured me the new stone roads would ensure excellent technical
support by the educated greek slave nerds, but they let me know that
ridding hum was 'not among the things they get forced to do.'.
Carlo