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Static noise help please

Recently just notice Static, hiss, popping sound(I don’t think I hear that before but I might be wrong) from both speakers when volume alway down with music off. Happen only when connected usb from iMac to Schitt Modi 2 Uber DAC. Static noise disappear after unplug either end of the usb. I am using temporally cheap 15 feet usb a/b cable. Pre amp is ARC LS7,ARC VS60 amp,and Sonus Faber Venere 2.5.  Any advise?
I swap from ARC setup above to Cary SLI80 interested amp and used the same usb cable and the static noise was gone. So I think it is not the usb cable problem. Is that possible static noise come from tubes?

Regards,
Eddy

eddy1
eddy1 OP
148 posts
 
ghosthouse,  Yes, I already have it and will try other too.  
Thank you,
eddy1 OP
148 posts
 
Received Certified USB cables but no different in static noise.  I am sure double-heated USB will solve my static problem.  Will give it a try.
eddy1 OP
148 posts
 
Hello ghousethouse and Spencer,
No more static noise by using double-heated USB (very easy to do it by myself, only cost less than $10).  By using 5V cell phone portable rechargeable battery I can hear hi pitch noise came from tweeter but my ear have to be very very close (almost have to touch the speaker grill) to be able to hear that hi pitch noise. I am waiting for USB power adapter wall charge that recommend from someone from other post to show up and will give it a try.  I don't know if I have to worry about those small hi pitch sound or not since it is can't really notice unless my ear have to be next to or touch tweeter speaker grill.  http://www.ebay.com/itm/Enercell-5V-1A-AC-to-USB-Power-Adapter-Charger-P-N-2730700-/321870766809?has...
Regards,
Eddy
ghosthouse's avatar
ghosthouse
4,321 posts
 
Eddie - glad to read splitting the USB cable got rid of the static.  That 5V Enercell on Ebay is the one I'm using.  It was originally recommended by Williewonka (a member of A'gon).  If you feel like it, I'd be very interested in a step by step procedure for how to build a 2 headed USB cable.    

eddy1 OP
148 posts
 
ghosthouse,
Here is what I did on the cable.  You need two USB A-B cables.

The purpose of this is only run data from your Mac to DAC without using noisy 5v power from your Mac.  So we have to run 5v directly  from wall charger to DAC.

1. cut out the first cable, will use only type A (this will go to wall charge)
    -  only use 2 wires:  red(+5V Vcc) and black(ground)
    This is power cable

2. second cable, open the cable shielded up (I did about 2" on mine so I can solder very easy) and you will see 4 wires(red(+), black(ground), green(data-), and white(data+).
    - cut only red and black wires
    - leave white and green wires alone
   (Type A end will go to your MAC and Type B will go to your DAC)

3.   Need to solder the first cable (power wires) type A to type B on the second cable so the DAC will get power directly from wall charger not from your Mac.  Do the following
     - solder the first cable red wire from type A to second cable type B red wire.
     - solder the first cable black wire from type A to second cable type B black wire.
     
     (This type A end will go to the wall charger and type B will go to DAC)

Sorry, it is a bit hard to explain in writing, I am sure someone will explain in writing much better than me but I can call you and explain on the phone better.   Just message me your phone number.

Regards,
Eddy
      
    
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