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    Simple, cost-free USB fix!

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    Gregg R.

    Posts : 78
    Join date : 2014-02-20
    Age : 72
    Location : Land of 11,842 Lakes

    Simple, cost-free USB fix!

    Post by Gregg R. on Mon Jun 15, 2015 1:56 am

    I have discovered a simple, cost-free fix for USB cables. It involves disconnecting the two 5v power wires inside the jacket. The close proximty of the data wires to power wires can contaminate the data stream. Here's how you do it:

    1. Slice open the insulation length-wise near the male A connector, the one that attaches to your computer.

    2. Pull out the bundle of 4 wires and two shields(braid and foil).

    3. Dig thru to find the heavier red and black 5v wires (the thinner green and white wires are for data).

    4. Snip off the red and black wires, sealing them shrink-tubing or tape. Otherwise, you risk shooting 5v thru the ground plane. It will mess up your USB bus.

    5. It's a good idea to roll some household foil over the bundle to ensure continous shielding. Tape it all up and hook it back up. You should hear a reduction in the "scrim" that seems to ride on top of computer audio.

    6. Some WARNINGS: Try this fix only with DACs that are AC powered. They usually don't need the 5v. Also, try this first with an expendable USB cable. Of course, after your DAC turns digits into analogue, hook it up to a Roy Mottram tube pre-amp and/or a Bob Latino tube power-amp!

    Note: I discovered this reading a TAS review of a $900 Audience USB cable. They separate the power and data wires with completely separate shields, jackets, and male A connectors. My way is cheaper.

    sKiZo

    Posts : 1312
    Join date : 2013-04-01
    Location : Michigan USA

    Re: Simple, cost-free USB fix!

    Post by sKiZo on Mon Jun 15, 2015 12:30 pm

    Good post ... have to give that a try on my Maverick TubeMagic!

    Another good trick - if you've got an open slot on your computer, install a USB add on card that taps juice directly off the power supply. This creates a new USB channel and isolates it completely from the main buss. Lot of noise can be generated by other USB devices and that can create crosstalk and dropouts on the audio. I did some serious head scratching here about various fartz 'n brapples on playback till I stumbled across this solution. Only the DAC and ADC are plugged into the expansion card - Nary a peep since.

    Just make sure the card has the correct power tap to fit one of your available connectors, or get the right adapter.

    PS ... also, use the shortest cable you can get away with. Even a cheepo 12" cable can outperform a three foot "quality" version.

    zx

    Posts : 194
    Join date : 2011-08-05

    Re: Simple, cost-free USB fix!

    Post by zx on Mon Jun 15, 2015 2:16 pm

    Yes great info thanks.....I need to get just...  the digital output ....out of my laptop USB....to run to my DACs input.....do you know how.....or if this can be done....?
    My Krell DAC has no USB input..........

    sKiZo

    Posts : 1312
    Join date : 2013-04-01
    Location : Michigan USA

    Re: Simple, cost-free USB fix!

    Post by sKiZo on Mon Jun 15, 2015 5:07 pm

    For that, you'll need a breakout box. Lucky you, there's a really inexpensive one that performs way beyond it's price point - I use mine for ripping vinyl and voicing the room using the laptop.

    Amazon has the Behringer UCA202 or $30 ... tops out at 48/16, but that's better than CD Redbook, and I've never really felt the need for more.

    PS ... The UCA202 bypasses the onboard audio of your laptop, which is probably a good thing, as it will more than likely give better results for digital playback. Wasn't till quite recently that the mfgs started paying attention to audio. If you really want it to sing, use Windows 8 and the WASAPI driver ... next best thing to bit perfect, so no hiccups or noise.

    Gregg R.

    Posts : 78
    Join date : 2014-02-20
    Age : 72
    Location : Land of 11,842 Lakes

    Re: Simple, cost-free USB fix!

    Post by Gregg R. on Tue Jun 16, 2015 2:09 am

    I have also discovered that the el cheapo USB cable that I first performed the surgery on, sounds better than my "reference" Belkin Gold after both were modded. I did a number of A/B listens to both wires. Before, the Belkin sounded better. Go figure!

    zx

    Posts : 194
    Join date : 2011-08-05

    Re: Simple, cost-free USB fix!

    Post by zx on Tue Jun 16, 2015 2:06 pm

    thanks for info....has anyone...ever seen one of these breakout boxes with a RCA digial output?

    zx

    Posts : 194
    Join date : 2011-08-05

    Re: Simple, cost-free USB fix!

    Post by zx on Fri Jun 26, 2015 6:40 pm

    Behringer UCA202 ....wow....best thing ever for my old Dell studio...laptop
    I got off CL $10new......digiel out to my Krell SBP 32X...D/A......killer tone...
    thanks for all the great info....guys





    thanks for the site Bob.........................

    arledgsc

    Posts : 340
    Join date : 2012-11-30
    Location : SF Bay CA

    Re: Simple, cost-free USB fix!

    Post by arledgsc on Sat Jun 27, 2015 12:47 pm

    Some audio USB interfaces need the +5V for detection that it is connected.  Some don't.  I bypass the PC +5V USB feed and run clean, linear +5V instead.   Good advice is to make sure the PC and your audio equipment are connected to the same AC power source.

    I just purchased this USB converter a few weeks ago and it is turning to be really good value.   Does up to 384K and DSD if that is your thing.  I had to modify the I2S output to reconfigure polarity of a few signals to match my DAC but easy with a $4 chip change.  But it sounds almost as good as my fancy USB converter that sells for 18x the price.

    I bought from Amazon for same price and received in 2 days.
    http://www.shenzhenaudio.com/gustard-u12-32bit-384khz-xmos-usb-digital-audio-interface.html

    zx

    Posts : 194
    Join date : 2011-08-05

    Re: Simple, cost-free USB fix!

    Post by zx on Sat Jun 27, 2015 4:37 pm

    bypass the PC +5V USB feed and run clean, linear +5V instead......yes I was thinking about that...but sand SS... an me find it tuf to get along .....when it comes to mods .....
    for better sound... if you use one of the Behringer UCA202 for digiel out.....if you use your own dac....don't run any other RCA to the 202 box......that way you have no com...from your laptop to preamp..... that way you have floted the ground output from the Audio chain

    like the shenzenaudio box...vary nice...with all the outputs.....an dsd...I gess, I have not got to hear dsd yet........looks good on paper..........thanks for the info





    thanks for the Site Bob..........................

    sKiZo

    Posts : 1312
    Join date : 2013-04-01
    Location : Michigan USA

    Re: Simple, cost-free USB fix!

    Post by sKiZo on Sat Jun 27, 2015 8:10 pm

    Clean power is covered with the use of an add on card I mentioned earlier. Look for one that has a power tap that plugs directly into the power supply, bypassing the system buss.



    Of course, that assUmes the availability of an open slot - or even a slot. Those are getting hard to come by. My new ITX motherboard had ONE, which fortunately, was all I needed.



    You can see it peeking out from the left of the fan ... those boards are getting small!

    Fun fact - an ITX board bolts right into an older ATX case, using the standard mounts.

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    Re: Simple, cost-free USB fix!

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