3 Apr
2010
3 Apr
'10
7:59 p.m.
On Sat, 3 Apr 2010 17:48:43 -0400 (EDT)
Rick Green <rtg(a)aapsc.com> wrote:
I'm using a FOcusrite Saffire pro 26 I/O with
ffado, jack, and Ardour to
make multitrack recordings of live concerts, to my emachines M6810 laptop
running ubuntustudio. I'm plagued by noise that sounds to me like RF
interference from the laptop, getting into the audio portions of the
interface. It's most obvious when I'm at home trying to mix down my
recordings, as its almost constant in my monitors and most noticable in
a quiet room, but it also manifests itself sometimes during shows, showing
up on the input lines to the interface, which are plugged 'half-way' into
the FOH mixer's channel inserts, so it invades the PA and the performers'
monitors. WHen that happens, I've no other choice but to abandon the
recording and shut down the laptop.
Has anyone else encountered this problem? Got any suggestions how to
filter it? I'm going to try some ferrite cores snapped around the
firewire cable first. Anything else I might try?
First question, is the laptop running from it's battery or the mains?
If battery, how good is it's charge retention?
If mains, is it a fully isolated PSU or is there a possible earth loop?
Note some PSUs are really nasty and have filtering caps that bridge
across L N & E
Do you get the same problem if you go via any route *other* than
firewire?
I don't know about laptops, but I've learned to avoid emachines
desktop machines like the plague. They are the crappiest build
imaginable :(
--
Will J Godfrey
http://www.musically.me.uk
Say you have a poem and I have a tune.
Exchange them and we can both have a poem, a tune, and a song.