rtrinidad
I've been reading post that suggest some noise problems are caused by a "ground loop" or by not grounding devices to each other.
I have:
Hercules RMX (USB powered off a laptop)
Powered Speakers (Connected to Hercules via 1/4" phono jacks)
Laptop (It's power plug is a two-pronged with no ground)
My questions are:
Do I need to ground the Hercules to the laptop? If so, how?
Do I need isolate the ground on the laptop? If so, how since it has no ground?
Do I need something between the Hercules and powered speakers to reduce noise? If so, what?
Should I use a powered USB hub to power the Hercules instead of using the laptop's USB power?
Should I lift the ground off the powered speakers?
Sorry for all the questions.
Robert
I have:
Hercules RMX (USB powered off a laptop)
Powered Speakers (Connected to Hercules via 1/4" phono jacks)
Laptop (It's power plug is a two-pronged with no ground)
My questions are:
Do I need to ground the Hercules to the laptop? If so, how?
Do I need isolate the ground on the laptop? If so, how since it has no ground?
Do I need something between the Hercules and powered speakers to reduce noise? If so, what?
Should I use a powered USB hub to power the Hercules instead of using the laptop's USB power?
Should I lift the ground off the powered speakers?
Sorry for all the questions.
Robert
Posté Thu 16 Jul 09 @ 11:11 am
tayla
you don't say whether your suffering from the problem, if not, i wouldn't worry about it.
Posté Thu 16 Jul 09 @ 12:58 pm
rtrinidad
OK, I'm suffering from the problem of a low hum and popping and crackling when using my configuration. I've been all over this forum and have tried all the suggestions including:
Turning off wireless, CD, network, etc.
Reducing my resolution and lowering my hardware acceleration
Checked latency
Changed my performance parameters all over the place
The only thing I haven't done is deal with ground loop (since I just started dealing with the hum). I know the concept of lifting the ground and have done this many times with regular sound equipment. I just don't know how to deal with the laptop and the USB Hercules RMX controller. I am new to computer DJing even though I'm computer savy except for midi.
Robert
Turning off wireless, CD, network, etc.
Reducing my resolution and lowering my hardware acceleration
Checked latency
Changed my performance parameters all over the place
The only thing I haven't done is deal with ground loop (since I just started dealing with the hum). I know the concept of lifting the ground and have done this many times with regular sound equipment. I just don't know how to deal with the laptop and the USB Hercules RMX controller. I am new to computer DJing even though I'm computer savy except for midi.
Robert
Posté Thu 16 Jul 09 @ 2:02 pm
JimmyL-DJ
Hi,
First see if the hum is eliminated by unconnecting your DC/AC feed to the laptop. I have terrible hum from my HP laptop transformer. Seems the newer the laptop the worse it gets. I think it is just bad filtering in the unit. Cheap cheap cheap.
I use an isolation transformer in line with my audio cable from the laptop soundcard to my mixer input. Something like this.
http://cgi.ebay.com/LAPTOP-HUM-ELIMINATOR-GROUND-LOOP-ISOLATOR_W0QQitemZ260399132032QQcmdZViewItemQQptZUK_Audio_TV_Electronics_In_Car_Entertainment_GPS_Car_Amplifiers_PP?hash=item3ca0ff6d80&_trksid=p3286.m63.l1177&_trkparms=%7C293%3A1%7C294%3A50
It might work for you. Experimentation is prudent. Good luck
If this is not the problem, perhaps going to all balanced connections and cables would help.
Regards,
Jkl
First see if the hum is eliminated by unconnecting your DC/AC feed to the laptop. I have terrible hum from my HP laptop transformer. Seems the newer the laptop the worse it gets. I think it is just bad filtering in the unit. Cheap cheap cheap.
I use an isolation transformer in line with my audio cable from the laptop soundcard to my mixer input. Something like this.
http://cgi.ebay.com/LAPTOP-HUM-ELIMINATOR-GROUND-LOOP-ISOLATOR_W0QQitemZ260399132032QQcmdZViewItemQQptZUK_Audio_TV_Electronics_In_Car_Entertainment_GPS_Car_Amplifiers_PP?hash=item3ca0ff6d80&_trksid=p3286.m63.l1177&_trkparms=%7C293%3A1%7C294%3A50
It might work for you. Experimentation is prudent. Good luck
If this is not the problem, perhaps going to all balanced connections and cables would help.
Regards,
Jkl
Posté Thu 16 Jul 09 @ 6:30 pm
tayla
perfectly good instructions to follow there Robert.
Posté Thu 16 Jul 09 @ 6:48 pm
purejuice
well I have had the same problem with noise and it was driving me nuts, so I unplugged the ac/adapter to my laptop and the noise stopped so I got a two prong adapter for the cord and then plugged it in, and the noise is no longer there.
Posté Thu 16 Jul 09 @ 6:59 pm
willk
You might also try this cheap fix. When using my lappy in a club, i bought whats called a " ground loop isolator " from radio shack. It costs 20 bucks. They are in the car audio section of the store. It only has phono in's and out's so be prepared to use some kind of adaptors depending on your specific use. I used this 20 dollar fix to take hum out of national acts when they wnat to plug into our house system. Mona Q as well as Khia have been saved by this inexpensive unit. This is a last chance fix if replacing audio cables or lifting the ground on your unit does not work. good luck ! =)
Posté Sun 26 Jul 09 @ 7:07 pm
DHoude
If you really feel the need to go this far on isolating the ground or your are working outdoors where things can get wet. Jensen transformers are ther best there is http://www.jensen-transformers.com/iso_vid.html . I use them on any Home Theater install that needs them and they come in all kinds of connections.
BUT, the 3 prong to 2 prong adaptor is fine in a pinch if you set is not a perminet install. Other than that, just plug all of your equipment AMPs and PC on the same circuit or plug strip (if you can) and all will be fine.
BUT, the 3 prong to 2 prong adaptor is fine in a pinch if you set is not a perminet install. Other than that, just plug all of your equipment AMPs and PC on the same circuit or plug strip (if you can) and all will be fine.
Posté Sun 26 Jul 09 @ 10:07 pm
kjdj99
Your feeding your balanced low impedance powered speaker input with a "consumer" unbalanced high impedance 1/4' connector output. Buy a Beringer or any brand direct box.
A direct box not only isolates the ground but also converts the unbalanced signal to balanced signal which will eliminate RF and common mode noise.
Use Balanced XLR cables between the direct box and your speakers.
Using an isolation transformer will kill the hum but it won't kill the other interference that enters the cables such as AM radio stations and lamp dimmers.
Kevin
A direct box not only isolates the ground but also converts the unbalanced signal to balanced signal which will eliminate RF and common mode noise.
Use Balanced XLR cables between the direct box and your speakers.
Using an isolation transformer will kill the hum but it won't kill the other interference that enters the cables such as AM radio stations and lamp dimmers.
Kevin
Posté Mon 27 Jul 09 @ 9:36 pm
Stretchincanada
had this issue and then changed a setting and it dissapeared.It was the actuall wall plug in wasnt grounded right.. so I had the entire house rewired.. so its all good in the end .
Posté Wed 14 Nov 12 @ 10:11 pm
Stretchincanada
try changing the usb cable as my cable extension didnt work... weired but true...customer was happy but had to pay me the 80$ for drop in...
Posté Sat 17 Nov 12 @ 2:37 am