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

Showing 13 responses by eddy1

Thank you Spencer for your advised.  Been driving around to find Certified USB but no luck.  So I ordered Blue Jean USB online and the price is real good.  I guess I have to wait for a week to find out.
ghosthouse, Yes, I tried all USB ports on my Mac and the Modi is far away from the monitor but still got static.  Will see if the certified USB would help but I don't think it would, well I will have to try.  Will report back when I the new USB come in.
Thank you,
Eddy
ghosthouse, Thank you for you responded.  The static noise is still there.  Windows were opened so I couldn't hear static at that time but after all windows closed I heard static noise again.  Did some search on Schitt Modi and found some people having the same problem.  Yes, it is low volume cracking noise and continue making same noise until I unplug usb cable.  Will not hear static noise when I play the music.   I will have to check with my Cary SLI80 again if it make noise like ARC to make sure.  This Modi is only $150, it might be too cheap that's why I having this problem.  I was going to spend $1,200-1,500 on DAC but something came up and need to use those money so I just pickup the Modi for temporary for couple of months and now I am afraid to buy Schiit Gungnir Multibit, might try different brand.  
Hello ghosthouse,  This guy on Computer Audiophile had similar problem and use something similar to Audioquest Jitterbug and solved his problem.  Here is the link, the last posted shown what he used,  http://www.computeraudiophile.com/f6-dac-digital-analog-conversion/noisy-schiit-modi-help-needed-oth...
What do you think about Audioquest Jitterbug and the one that he used here
 https://electronics-shop.dk/galvanically_usb_isolation.htm?currency=EUR

The guy at Schiit told me to try certified USB 2.0 under 2 meters.  And I don't think this is the problem because I did with 4 feet USB and still got static but will go out and buy certified one to try out today if I can find one, mostly have to order online.   
After been reading so many posts and many searched, my conclusion is Dirty power (5V) from computer to the USB.  So my plan was going to cutout 5V +(Vcc) and -(Ground) cables from USB and will only run Data to DAC but found out that all Schiit needed 5V from USB.  
Spencer, ghosthouse,  Thank you.  I think I will do double headed USB cable myself.  I have USB certified 10 feet and 6 feet coming so I will give it a try.  But will try with 5V DC (http://www.amazon.com/Sony-CPV3-2800mAh-Portable-Supply/dp/B00FAJYO58) first then will order wall plug Emercell.

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.
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,
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