Stanton DJ Knowledge Base

I am hearing an odd noise when I connect the Scratchamp to the computer.

Troubleshooting Details

  1. Verify the Ground Loop
  2. Addressing the Problem
  3. What if I Still Have Noise?

Verifying the Ground Loop
The first thing we need to do is to figure out if a ground loop is indeed your problem.  The way to do this is to temporarily lift the ground of the computer your Scratchamp is connected to.  If you’re using a laptop, this is easily enough done by simply running off the battery and not having it plugged into an AC outlet.

On a desktop this is a little more complicated.  If you have an UNGROUNDED extension cord, you can temporarily plug your computer’s power cord into this instead of directly into the outlet.  You can also use a “Grounding Adapter” (Radio Shack part number 61-2720) as a temporary ground lift.
 

In either case, if the noise goes away when you remove the ground, chances are good that you do have a ground loop.

 

Addressing the Problem

Lifting the ground gets rid of your noise, but removing an equipment ground isn’t a good idea.  The easiest way to try and address a ground loop is to arrange your power so that the computer and Scratchamp are plugged into the same outlet (and thus sharing the same ground).  Sometimes simply re-arranging your power connections can fix a ground loop.  If this doesn’t work, more drastic measures are necessary.

The cheapest product available to address ground loops is called a Ground Loop Isolator (or GLI for short).  It looks like a typical RCA cable with a large cylinder in the middle.  These are commonly used to fix ground loop issues in car stereos, and can usually be purchased in places that do stereo installations.  You can also find them at electronics stores (Radio Shack part number 270-054).

 

If your mixer has XLR outputs (or if you desire a higher quality device), most Direct Boxes (DIs for short) have a ground lift switch.  These can most easily be purchased at any local music store.

Both of the above products reside in the audio signal path, and as such have the ability to color your sound.  A less impactful (albeit more expensive) way of addressing ground loops is through power conditioning.  Many of these systems are large and not very portable, but the company Ebtech makes a product called the HumX that is only a little bigger than the power plug itself and addresses ground loops while still maintaining an electrical ground.

 

What If I Still Have Noise?

If you’ve lifted the ground on your computer and are still getting the noise, it’s possible that you still have a ground loop, but that it’s manifested itself somewhere else in the signal path.  With everything plugged in, try unplugging one component at a time (except the computer and mixer) until you hear the noise disappear.  If you find an offending device, try lifting the ground of that particular device.  If this is successful, address the problem more permanently using one of the methods outlined above.

 

If your search was unsuccessful, check for other sources of noise.  Are your gains set so high that signals are clipping (and bleeding through to adjacent channels of your mixer)?  Do you have power cords running parallel with audio cords?  Or are your audio cables running very close to devices that may possibly have poor shielding?  Are your turntables properly grounded to your mixer?  Is anything sharing power with a mechanical device (excluding your decks)?  Switching power supplies, relays, and electrical motors can be major sources of noise.

 

Would you like to...

Print this page Print this page

Email this page Email this page

Post a comment Post a comment

Subscribe me

Add to favorites Add to favorites

Remove Highlighting Remove Highlighting

Edit this Question

User Opinions (15 votes)

100% thumbs up 0% thumbs down

How would you rate this answer?



Thank you for rating this answer.

Related Questions

No related questions were found.

Attachments

No attachments were found.

Visitor Comments

  1. Comment #1 (Posted by ghd styler )
    Rsultats du GRN. 4x50 nage libre dames: 2e le GRN. [url=http://www.cycles-cad.com/LisseurGhd-fr.php]ghd styler[/url] <a href="http://www.cycles-cad.com/LisseurGhd-fr.php" title="ghd styler">ghd styler</a>
  2. Comment #2 (Posted by iphone4s ??? )
    ????????)????????????????????????? ????????????????????????????????????=??????????????(31)=???? ?????????????????????????????????????=????????????(44)????????????(63)?=??????????? and roll back the specter of a warming planet. the market can spin out of control - and that a nation cannot prosper long when it favors only the prosperous.??????????????????????????????????????????????????????????????????????????????????????????????????????????????????29????66?1?
  3. Comment #3 (Posted by miled )
    nothing just music plz
  4. Comment #4 (Posted by GeorgeVoism )
    &#1071; &#1080;&#1079;&#1074;&#1080;&#1085;&#1103;&#1102;&#1089;&#1100;, &#1085;&#1086;, &#1087;&#1086;-&#1084;&#1086;&#1077;&#1084;&#1091;, &#1042;&#1099; &#1085;&#1077; &#1087;&#1088;&#1072;&#1074;&#1099;. &#1071; &#1091;&#1074;&#1077;&#1088;&#1077;&#1085;. &#1044;&#1072;&#1074;&#1072;&#1081;&#1090;&#1077; &#1086;&#1073;&#1089;&#1091;&#1076;&#1080;&#1084; &#1101;&#1090;&#1086;. --- &#1087;&#1086;&#1088;&#1085;&#1086; &#1088;&#1072;&#1089;&#1089;&#1082;&#1072;&#1079;&#1099; &#1082;&#1072;&#1082; &#1103; &#1089; &#1076;&#1088;&#1091;&#1079;&#1100;&#1103;&#1084;&#1080; &#1074;&#1099;&#1077;&#1073;&#1072;&#1083;&#1080; &#1084;&#1086;&#1102; &#1084;&#1072;&#1090;&#1100; &#1072; &#1090;&#1072;&#1082;&#1078;&#1077; <a href=http://porno-incest.ru/incest/4721-porno-rasskaz--laquomat-i-dochka-za-sredstva.html>&#1087;&#1086;&#1088;&#1085;&#1086; &#1088;&#1072;&#1089;&#1089;&#1082;&#1072;&#1079;&#1099; &#1087;&#1072;&#1087;&#1072; &#1082;&#1086;&#1085;&#1095;&#1072;&#1077;&#1090; &#1074;&#1086; &#1074;&#1083;&#1072;&#1075;&#1072;&#1083;&#1080;&#1097;&#1077; &#1076;&#1086;&#1095;&#1077;&#1088;&#1080;</a>
  5. Comment #5 (Posted by Cosette )
    tinyurl.com/huuv8ns#NpKDnrK 100 day lans. tinyurl.com/jq66zo4#XfSPefT 100 da 1ns is grt otin fr thos loing fr cash quil fo n sn. ****1ik he f instant cess****. hw d yu paycheck payday loan first american credit payday loan loan houston 300 doller lones easy signature loan bad credit ----->>>>> tinyurl.com/hyucaxy#XhJPvoF
  6. Comment #6 (Posted by Cameal )
    qui sh tinyurl.com/jq66zo4#IcGQwgT instal1nt 1ans. he; /; quik sh tinyurl.com/jghm4af#FuXDjzS inst1lmnt 1ns. fr nything from hm iprovmnts t onsidr its ttl amunt you miss yur finncs cash advances in akron cash advance direct deposit cash advance pawtucket ri brightstar loans 100 loan for 2 weeks ===>>>>> http://tinyurl.com/zuvg27v#ZtSEksG
  7. Comment #7 (Posted by Cathie )
    breast actives tinyurl.com/h543e5n#phsffqo vs brestrogen which is the better breast cream active, my exercise routine consists mostly of jogging and strength training 4-5 times per week. --->> tinyurl.com/zdd7rcd#PdCCmcO

Post a comment

To post a comment for this question, simply complete the form below. Fields marked with an asterisk are required.
   Name:
   Email:
* Comment:
* Enter the code below:
 

Continue