19 May
2007
19 May
'07
6:06 a.m.
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I plugged my spiffy new linux laptop into an amp tonight and used it as an instrument with
a band, using an M-Audio Axiom49 as a MIDI controller.
Not everything works yet on this new machine, but what I needed most for tomorrow
night's show (specimen, with a couple specialized samples), worked fine.
Except for the noise. The FA-66 was producing the most awful, buzzy, glitchy digital
background noise.
I ran the following chain, and got horrible aliasing noise:
Laptop ->
ExpressCard Firewire ->
FA-66 ->
SWR bass/keyboard amp
The FA-66 is powered by its wall-wart, since the ExpressCard doesn't power it (even
though it is a 6-pin connector).
My question is this. What's up with that awful noise?
Tonight's workaround was to unplug the FA-66 from the amp, and plug it in only for the
few bars at the end of the one song where I need to trigger the samples, and then unplug
it again.
The laptop's power supply is grounded (three-prong) but the FA-66's wall-wart
isn't. I thought of trying to ground the FA-66 to the power strip's ground, but
then I noted that:
1) This doesn't sound to me like 60-cycle hum, though it has a little bit of that too
(bummer I didn't think to record it and post it). It's digital noise, and I'm
not sure grounding would help.
2) I have no guarantees that the club I'm playing at tomrrrow night will have a
decent ground. I've been in some that have pretty sketchy electrical systems.
Alas, I'm borrowing this amp, and I don't have an amp anymore, I play through my
stereo. The FA-66 sounds amazing through the stereo. So this means that I don't have
the ability to duplicate the problem at home.
I didn't think to try my Audiophile USB interface, because the FA-66 is much
"higher end" and I didn't expect the lower-end interface to be immune to
this problem if the higher-end one has it.
However, a possibly-related problem is that the FA-66 has really low-level line outputs. I
notice this when playing through my stereo too, but I didn't think much about it until
now. But maybe it is related?
Anyway, I'm not much of an audio engineer, so I figured I'd ask here, in case
someone's been through this and fixed it.
- -ken
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19 May
19 May
7:12 a.m.
Ken Restivo wrote:
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I plugged my spiffy new linux laptop into an amp tonight and used it
as an instrument with a band, using an M-Audio Axiom49 as a MIDI
controller.
Not everything works yet on this new machine, but what I needed most
for tomorrow night's show (specimen, with a couple specialized
samples), worked fine.
Except for the noise. The FA-66 was producing the most awful, buzzy,
glitchy digital background noise.
I ran the following chain, and got horrible aliasing noise: Laptop ->
ExpressCard Firewire -> FA-66 -> SWR bass/keyboard amp
The FA-66 is powered by its wall-wart, since the ExpressCard doesn't
power it (even though it is a 6-pin connector).
My question is this. What's up with that awful noise?
When googling around I found at least one other person having the same
issue with the FA-66.
I've noticed similar noise at some places with my QuataFire line out's.
Some things to try:
- unplug the power supply of the laptop (for test)
- put a DI box inbetween the amp and the edirol (enable ground lift)
- use another power supply for the edirol (preferably a transformer
based one).
Pieter
7:18 a.m.
Hallo!
> Except for the noise. The FA-66 was producing the
most awful, buzzy,
> glitchy digital background noise.
Yes, this is common with laptop and external soundcards ... ;)
Some things to try:
- unplug the power supply of the laptop (for test)
- put a DI box inbetween the amp and the edirol (enable ground lift)
- use another power supply for the edirol (preferably a transformer
based one).
Or cut the ground ... ;)
LG
Georg
7:40 a.m.
Pieter Palmers wrote:
Ken Restivo wrote:
http://docs.info.apple.com/article.html?artnum=86655
Pieter
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I plugged my spiffy new linux laptop into an amp tonight and used it
as an instrument with a band, using an M-Audio Axiom49 as a MIDI
controller.
Not everything works yet on this new machine, but what I needed most
for tomorrow night's show (specimen, with a couple specialized
samples), worked fine.
Except for the noise. The FA-66 was producing the most awful, buzzy,
glitchy digital background noise.
I ran the following chain, and got horrible aliasing noise: Laptop ->
ExpressCard Firewire -> FA-66 -> SWR bass/keyboard amp
The FA-66 is powered by its wall-wart, since the ExpressCard doesn't
power it (even though it is a 6-pin connector).
My question is this. What's up with that awful noise?
When googling around I found at least one other person having the same
issue with the FA-66.
I've noticed similar noise at some places with my QuataFire line out's.
Some things to try:
- unplug the power supply of the laptop (for test)
- put a DI box inbetween the amp and the edirol (enable ground lift)
- use another power supply for the edirol (preferably a transformer
based one).
24 May
24 May
9:36 p.m.
New subject: Awful noise out of FA-66 -- SOLVED
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On Sat, May 19, 2007 at 11:40:16AM +0200, Pieter Palmers wrote:
Pieter Palmers wrote:
Thanks for your help! The USB M-Audio Audiophile exhibited the same noise problem. Then I
unplugged the laptop's power supply and ran off of batteries, as you suggested, and
there was blissful silence!
The problem was the power supply.
Any advice on brands/distributors of good *quiet* laptop power supplies? The cheap-ass
"Delta Electronics" supply (19v, 3.6A) that came with the laptop obviously
sucks, and the only other 19v laptop power supplies I have around here are only 1.8A.
- -ken
Ken Restivo wrote:
http://docs.info.apple.com/article.html?artnum=86655
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I plugged my spiffy new linux laptop into an amp tonight and used it
as an instrument with a band, using an M-Audio Axiom49 as a MIDI
controller.
Not everything works yet on this new machine, but what I needed most
for tomorrow night's show (specimen, with a couple specialized
samples), worked fine.
Except for the noise. The FA-66 was producing the most awful, buzzy,
glitchy digital background noise.
I ran the following chain, and got horrible aliasing noise: Laptop ->
ExpressCard Firewire -> FA-66 -> SWR bass/keyboard amp
The FA-66 is powered by its wall-wart, since the ExpressCard doesn't
power it (even though it is a 6-pin connector).
My question is this. What's up with that awful noise?
When googling around I found at least one other person having the same
issue with the FA-66.
I've noticed similar noise at some places with my QuataFire line out's.
Some things to try:
- unplug the power supply of the laptop (for test)
- put a DI box inbetween the amp and the edirol (enable ground lift)
- use another power supply for the edirol (preferably a transformer
based one).
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10:48 p.m.
New subject: Awful noise out of FA-66 -- SOLVED
On 5/25/07, Ken Restivo <ken(a)restivo.org> wrote:
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On Sat, May 19, 2007 at 11:40:16AM +0200, Pieter Palmers wrote:
Have you tried groundlifting the power supply? Worked for me... until
i found a better solution, throwing out the laptop and getting a
desktop. ;)
Loki
Pieter Palmers wrote:
Thanks for your help! The USB M-Audio Audiophile exhibited the same noise
problem. Then I unplugged the laptop's power supply and ran off of
batteries, as you suggested, and there was blissful silence!
The problem was the power supply.
Any advice on brands/distributors of good *quiet* laptop power supplies? The
cheap-ass "Delta Electronics" supply (19v, 3.6A) that came with the laptop
obviously sucks, and the only other 19v laptop power supplies I have around
here are only 1.8A.
- -ken Ken Restivo wrote:
http://docs.info.apple.com/article.html?artnum=86655
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I plugged my spiffy new linux laptop into an amp tonight and used it
as an instrument with a band, using an M-Audio Axiom49 as a MIDI
controller.
Not everything works yet on this new machine, but what I needed most
for tomorrow night's show (specimen, with a couple specialized
samples), worked fine.
Except for the noise. The FA-66 was producing the most awful, buzzy,
glitchy digital background noise.
I ran the following chain, and got horrible aliasing noise: Laptop ->
ExpressCard Firewire -> FA-66 -> SWR bass/keyboard amp
The FA-66 is powered by its wall-wart, since the ExpressCard doesn't
power it (even though it is a 6-pin connector).
My question is this. What's up with that awful noise?
When googling around I found at least one other person having the same
issue with the FA-66.
I've noticed similar noise at some places with my QuataFire line out's.
Some things to try:
- unplug the power supply of the laptop (for test)
- put a DI box inbetween the amp and the edirol (enable ground lift)
- use another power supply for the edirol (preferably a transformer
based one).
25 May
25 May
1:02 p.m.
New subject: Awful noise out of FA-66 -- SOLVED
On Fri, May 25, 2007 at 10:48:09AM +1000, Loki Davison wrote:
On 5/25/07, Ken Restivo <ken(a)restivo.org>
wrote:
I've also found that to help sometimes. But lifting ground can be
unsafe. You never want your own body to be the best available path to
ground!
So if lifting the ground works, this might be a safer solution
(haven't tried one yet): http://www.ebtechaudio.com/humxdes.html
OTOH, I found this comment about that device on rec.audio.pro:
"To isolate safety ground requires a real isolation transformer, which
is neither small nor cheap."
and a bit more googling turned up this:
http://reviews.harmony-central.com/reviews/Effects/product/Ebtech/Hum-X/10/1
--
Paul Winkler
http://www.slinkp.com
The problem was the power supply.
Any advice on brands/distributors of good *quiet* laptop power supplies?
The
cheap-ass "Delta Electronics" supply (19v, 3.6A) that came with the laptop
obviously sucks, and the only other 19v laptop power supplies I have around
here are only 1.8A.
- -ken
Have you tried groundlifting the power supply? Worked for me... until
i found a better solution, throwing out the laptop and getting a
desktop. ;) 
1:54 p.m.
New subject: Awful noise out of FA-66 -- SOLVED
On Friday 25 May 2007 02:48, Loki Davison wrote:
On 5/25/07, Ken Restivo <ken(a)restivo.org>
wrote:
A couple of thoughts Loki. Would an AC filter (such as on old computer
equipment) resolve a problem like this ? Or perhaps one of those ferrite
cores, like are on the monitor cable, and I see I have one on my webcam cable
as well.
I did see the ferrite core option suggested some time back when someone had
interference showing up on sound output.
Nigel.
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On Sat, May 19, 2007 at 11:40:16AM +0200, Pieter Palmers wrote:
Have you tried groundlifting the power supply? Worked for me... until
i found a better solution, throwing out the laptop and getting a
desktop. ;)
Loki Pieter Palmers wrote:
Thanks for your help! The USB M-Audio Audiophile exhibited the same noise
problem. Then I unplugged the laptop's power supply and ran off of
batteries, as you suggested, and there was blissful silence!
The problem was the power supply.
Any advice on brands/distributors of good *quiet* laptop power supplies?
The cheap-ass "Delta Electronics" supply (19v, 3.6A) that came with the
laptop obviously sucks, and the only other 19v laptop power supplies I
have around here are only 1.8A.
- -ken Ken Restivo wrote:
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>
>I plugged my spiffy new linux laptop into an amp tonight and used it
>as an instrument with a band, using an M-Audio Axiom49 as a MIDI
>controller.
>
>Not everything works yet on this new machine, but what I needed most
>for tomorrow night's show (specimen, with a couple specialized
>samples), worked fine.
>
>Except for the noise. The FA-66 was producing the most awful, buzzy,
>glitchy digital background noise.
>
>I ran the following chain, and got horrible aliasing noise: Laptop ->
> ExpressCard Firewire -> FA-66 -> SWR bass/keyboard amp
>
>The FA-66 is powered by its wall-wart, since the ExpressCard doesn't
>power it (even though it is a 6-pin connector).
>
>My question is this. What's up with that awful noise?
When googling around I found at least one other person having the same
issue with the FA-66.
I've noticed similar noise at some places with my QuataFire line
out's.
Some things to try:
- unplug the power supply of the laptop (for test)
- put a DI box inbetween the amp and the edirol (enable ground lift)
- use another power supply for the edirol (preferably a transformer
based one).
http://docs.info.apple.com/article.html?artnum=86655
6445
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linux-audio-user@lists.linuxaudio.org
7 comments
6 participants
participants (6)
-
Georg Holzmann -
Ken Restivo -
Loki Davison -
Nigel Henry -
Paul Winkler -
Pieter Palmers