Author Topic: Sudden weak left channel with USB dac and extension cable  (Read 4473 times)

0 Members and 1 Guest are viewing this topic.

Offline qguy

  • Trade Count: (+18)
  • PinoyDVD Legend
  • *****
  • Posts: 3,762
  • Usher/Rythmik/S
  • Liked:
  • Likes Given: 52
Setup.

Netbook -> 5 meter USB  extension -> USB Dac - Interconnect -> Amplifier.

This has been working for several months without problems. Then earlier today I noticed my left channel was very weak. Switched to FM and no issus, so the problem was only in the netbook / Dac source. Initially i thought my DAC was the problem, checked for loose connections, change interconnect . Still the Same, not sure why I tried it but I removed the USB Extension cable and the problem was removed.  Reconnected it and the problem was again present.

Now heres, the thing, The USB cable does not have left and right channels, its just one wire for data, which contains left and right channel  info and the rest for ground and power, so why is it that only my LEFT channel is affected ???

Offline Nelson de Leon

  • Trade Count: (+141)
  • PinoyDVD Legend
  • *****
  • Posts: 10,084
  • Let us lead by example
  • Liked:
  • Likes Given: 291
Re: Sudden weak left channel with USB dac and extension cable
« Reply #1 on: Oct 17, 2012 at 10:00 PM »
Nagka handshake issues sa USB wire?

Offline Stagea

  • Trade Count: (+23)
  • PinoyDVD Legend
  • *****
  • Posts: 6,744
  • Hype Fidelity
  • Liked:
  • Likes Given: 600
Re: Sudden weak left channel with USB dac and extension cable
« Reply #2 on: Oct 18, 2012 at 02:40 AM »
Setup.

Netbook -> 5 meter USB  extension -> USB Dac - Interconnect -> Amplifier.

This has been working for several months without problems. Then earlier today I noticed my left channel was very weak. Switched to FM and no issus, so the problem was only in the netbook / Dac source. Initially i thought my DAC was the problem, checked for loose connections, change interconnect . Still the Same, not sure why I tried it but I removed the USB Extension cable and the problem was removed.  Reconnected it and the problem was again present.

Now heres, the thing, The USB cable does not have left and right channels, its just one wire for data, which contains left and right channel  info and the rest for ground and power, so why is it that only my LEFT channel is affected ???

There might be a large voltage drop from the long cable, enough to affect your DAC's operation. Are you using an active extension / repeater cable? If not, I suggest you try one.

Equipment deteriorate over time, and your DAC may be less tolerant of the low voltage now than it was before. Of course, it could also be a deteriorated cable/port or the computer delivering a lower voltage on the 5V line.
« Last Edit: Oct 18, 2012 at 02:41 AM by Stagea »

Offline qguy

  • Trade Count: (+18)
  • PinoyDVD Legend
  • *****
  • Posts: 3,762
  • Usher/Rythmik/S
  • Liked:
  • Likes Given: 52
Re: Sudden weak left channel with USB dac and extension cable
« Reply #3 on: Oct 18, 2012 at 05:55 AM »
No repeater or active extension, just plain Audiophile High End,  Less loss, Low Noise cable, High Purity Cable from CDR King :). Will get a new one later and see how it does.



There might be a large voltage drop from the long cable, enough to affect your DAC's operation. Are you using an active extension / repeater cable? If not, I suggest you try one.

Equipment deteriorate over time, and your DAC may be less tolerant of the low voltage now than it was before. Of course, it could also be a deteriorated cable/port or the computer delivering a lower voltage on the 5V line.

Offline Stagea

  • Trade Count: (+23)
  • PinoyDVD Legend
  • *****
  • Posts: 6,744
  • Hype Fidelity
  • Liked:
  • Likes Given: 600
Re: Sudden weak left channel with USB dac and extension cable
« Reply #4 on: Oct 18, 2012 at 06:07 AM »
No repeater or active extension, just plain Audiophile High End,  Less loss, Low Noise cable, High Purity Cable from CDR King :). Will get a new one later and see how it does.

Great. :) Consider an active extension if you're getting a 5m or longer one (since the total length would be greater once you put in your DAC's cable).

Your high end provider might have it in stock:
http://www.cdrking.com/?mod=products&type=view&sid=11956&main=4

Offline qguy

  • Trade Count: (+18)
  • PinoyDVD Legend
  • *****
  • Posts: 3,762
  • Usher/Rythmik/S
  • Liked:
  • Likes Given: 52
Re: Sudden weak left channel with USB dac and extension cable
« Reply #5 on: Oct 18, 2012 at 07:36 AM »
Tried that one, sadly the USB connection on the PC side easily gets loose.

Offline Nelson de Leon

  • Trade Count: (+141)
  • PinoyDVD Legend
  • *****
  • Posts: 10,084
  • Let us lead by example
  • Liked:
  • Likes Given: 291
Re: Sudden weak left channel with USB dac and extension cable
« Reply #6 on: Oct 18, 2012 at 07:50 AM »
You might want to borrow my powered USB 2.0 port for testing purposes.

Offline qguy

  • Trade Count: (+18)
  • PinoyDVD Legend
  • *****
  • Posts: 3,762
  • Usher/Rythmik/S
  • Liked:
  • Likes Given: 52
Re: Sudden weak left channel with USB dac and extension cable
« Reply #7 on: Oct 18, 2012 at 08:28 AM »
Thanks for the offer.. Sadly North and South locations natin.  Where did you get yours ?


You might want to borrow my powered USB 2.0 port for testing purposes.
« Last Edit: Oct 18, 2012 at 08:31 AM by qguy »

Offline JojoD818

  • Trade Count: (+147)
  • PinoyDVD Legend
  • *****
  • Posts: 14,558
  • Bring it on!
  • Liked:
  • Likes Given: 57
Re: Sudden weak left channel with USB dac and extension cable
« Reply #8 on: Oct 18, 2012 at 10:22 AM »
surely you can carry the laptop near the USB DAC and then plug the USB DAC directly to your laptop. also check the interconnect between your DAC and amplifier.

try those first before thinking of other stressful things.


Offline Nelson de Leon

  • Trade Count: (+141)
  • PinoyDVD Legend
  • *****
  • Posts: 10,084
  • Let us lead by example
  • Liked:
  • Likes Given: 291
Re: Sudden weak left channel with USB dac and extension cable
« Reply #9 on: Oct 18, 2012 at 10:24 AM »
Thanks for the offer.. Sadly North and South locations natin.  Where did you get yours ?

I bought it from a computer shop.

Offline JoeyGS

  • Trade Count: (+28)
  • PinoyDVD Legend
  • *****
  • Posts: 2,717
  • Let your ears decide!
  • Liked:
  • Likes Given: 181
Re: Sudden weak left channel with USB dac and extension cable
« Reply #10 on: Oct 18, 2012 at 10:39 AM »
+1

Try with a short regular usb cable, because you may have a disconnected wire.  Also, test the rest of the cable system by isolating your digital source.  Install another source, CD/DVD player perhaps, and see if there is no problem from the rest of the components (including speaker cables)


surely you can carry the laptop near the USB DAC and then plug the USB DAC directly to your laptop. also check the interconnect between your DAC and amplifier.

try those first before thinking of other stressful things.



Offline qguy

  • Trade Count: (+18)
  • PinoyDVD Legend
  • *****
  • Posts: 3,762
  • Usher/Rythmik/S
  • Liked:
  • Likes Given: 52
Re: Sudden weak left channel with USB dac and extension cable
« Reply #11 on: Oct 18, 2012 at 10:53 AM »
Tried these and the problem only appears when the extension USB cable is present. Connecting the netbook directly to the USB Dac removes the problem. 


surely you can carry the laptop near the USB DAC and then plug the USB DAC directly to your laptop. also check the interconnect between your DAC and amplifier.

try those first before thinking of other stressful things.


+1

Try with a short regular usb cable, because you may have a disconnected wire.  Also, test the rest of the cable system by isolating your digital source.  Install another source, CD/DVD player perhaps, and see if there is no problem from the rest of the components (including speaker cables)



Offline JojoD818

  • Trade Count: (+147)
  • PinoyDVD Legend
  • *****
  • Posts: 14,558
  • Bring it on!
  • Liked:
  • Likes Given: 57
Re: Sudden weak left channel with USB dac and extension cable
« Reply #12 on: Oct 18, 2012 at 10:56 AM »
Tried these and the problem only appears when the extension USB cable is present. Connecting the netbook directly to the USB Dac removes the problem. 




I can only think of one thing that can cause that, you are not powering your USB DAC optimally due to the long cable.


Offline AppleMan

  • Trade Count: (+2)
  • DVD Addict
  • ***
  • Posts: 809
  • Liked:
  • Likes Given: 7
Re: Sudden weak left channel with USB dac and extension cable
« Reply #13 on: Oct 18, 2012 at 04:05 PM »
^_Maybe the USB extension cable isn't good quality.....
KEF Q100
NAD C326BEE

Offline JoeyGS

  • Trade Count: (+28)
  • PinoyDVD Legend
  • *****
  • Posts: 2,717
  • Let your ears decide!
  • Liked:
  • Likes Given: 181
Re: Sudden weak left channel with USB dac and extension cable
« Reply #14 on: Oct 18, 2012 at 04:10 PM »
If a short USB cable would work then you need to power up your usb connection.

Offline Nelson de Leon

  • Trade Count: (+141)
  • PinoyDVD Legend
  • *****
  • Posts: 10,084
  • Let us lead by example
  • Liked:
  • Likes Given: 291
Re: Sudden weak left channel with USB dac and extension cable
« Reply #15 on: Oct 18, 2012 at 05:48 PM »
^_Maybe the USB extension cable isn't good quality.....

Minsan kasi sir, maski maganda ata ang quality, sa haba ng wire, nagkakaroon ng resistance na.

Offline ProtegeManiac

  • Trade Count: (+5)
  • DVD Addict
  • ***
  • Posts: 531
  • Hi, I'm new here!
  • Liked:
  • Likes Given: 0
Re: Sudden weak left channel with USB dac and extension cable
« Reply #16 on: Oct 18, 2012 at 09:46 PM »
surely you can carry the laptop near the USB DAC and then plug the USB DAC directly to your laptop. also check the interconnect between your DAC and amplifier.

Just to add, there are remote apps for Android and iOS phones and other devices, for some media players. There's MonkeyMote for MediaMonkey, for example. That way you can keep the computer near the other equipment and you can sit back, or work elsewhere in the room or house, and use your phone or tablet to control your main audio or multi-room background music system. Remote works via WiFi so no need for line of sight to use.

Offline JojoD818

  • Trade Count: (+147)
  • PinoyDVD Legend
  • *****
  • Posts: 14,558
  • Bring it on!
  • Liked:
  • Likes Given: 57
Re: Sudden weak left channel with USB dac and extension cable
« Reply #17 on: Oct 18, 2012 at 10:13 PM »
Just to add, there are remote apps for Android and iOS phones and other devices, for some media players. There's MonkeyMote for MediaMonkey, for example. That way you can keep the computer near the other equipment and you can sit back, or work elsewhere in the room or house, and use your phone or tablet to control your main audio or multi-room background music system. Remote works via WiFi so no need for line of sight to use.

Dang, I really need to brush up on those Android gadgets... :)

Offline Stagea

  • Trade Count: (+23)
  • PinoyDVD Legend
  • *****
  • Posts: 6,744
  • Hype Fidelity
  • Liked:
  • Likes Given: 600
Re: Sudden weak left channel with USB dac and extension cable
« Reply #18 on: Oct 19, 2012 at 03:43 AM »
Minsan kasi sir, maski maganda ata ang quality, sa haba ng wire, nagkakaroon ng resistance na.

The USB spec recommends a maximum total cable length of 3 - 5m because of electrical and timing constraints (3m for USB 1.1 and 3.0, and 5m for USB 2.0). Active extenders/repeaters/boosters/etc. allow for longer extension cables by buffering and relaying data traffic passing through the data pins at the proper signalling level. Better ones also regulate the output of the power pins to the USB spec (5V +/- 5%).

Tried these and the problem only appears when the extension USB cable is present. Connecting the netbook directly to the USB Dac removes the problem. 

You can also try hooking up a powered hub between the extension cable and your DAC. :)
« Last Edit: Oct 19, 2012 at 03:48 AM by Stagea »

Offline ProtegeManiac

  • Trade Count: (+5)
  • DVD Addict
  • ***
  • Posts: 531
  • Hi, I'm new here!
  • Liked:
  • Likes Given: 0
Re: Sudden weak left channel with USB dac and extension cable
« Reply #19 on: Oct 19, 2012 at 03:31 PM »
Dang, I really need to brush up on those Android gadgets... :)

Focus on the USB Audio feature Sir Jojo, some have a new kind of USB host protocol (even the ones that work with self-powered USB DACs have issues sometimes). There might be a market for USB (NOS?) DACs with Android-compatible USB DACs; at least unlike Apple (with the exception of the iPad), you won't need to license that chip that enables using it as a transport.


Offline JojoD818

  • Trade Count: (+147)
  • PinoyDVD Legend
  • *****
  • Posts: 14,558
  • Bring it on!
  • Liked:
  • Likes Given: 57
Re: Sudden weak left channel with USB dac and extension cable
« Reply #20 on: Oct 19, 2012 at 05:25 PM »
Focus on the USB Audio feature Sir Jojo, some have a new kind of USB host protocol (even the ones that work with self-powered USB DACs have issues sometimes). There might be a market for USB (NOS?) DACs with Android-compatible USB DACs; at least unlike Apple (with the exception of the iPad), you won't need to license that chip that enables using it as a transport.



They must have deviated from the usual protocols to protect their interests in the compatible ones. I hear the new iPhone has also deviated from the usual too. Anyway, I just want to get a simple Android and dive with whatever it can offer me. ;D

Offline ProtegeManiac

  • Trade Count: (+5)
  • DVD Addict
  • ***
  • Posts: 531
  • Hi, I'm new here!
  • Liked:
  • Likes Given: 0
Re: Sudden weak left channel with USB dac and extension cable
« Reply #21 on: Oct 19, 2012 at 09:30 PM »
They must have deviated from the usual protocols to protect their interests in the compatible ones. I hear the new iPhone has also deviated from the usual too. Anyway, I just want to get a simple Android and dive with whatever it can offer me. ;D

Samsung went back to the old system with the S3 and the Note2, most likely because the USB audio petition to Android developers really got a lot of attention. They're anticipating audio geeks finally getting tired of lugging around a separate phone and quality music player/transport and you won't hear your phone ringing while listening.
« Last Edit: Oct 19, 2012 at 09:36 PM by ProtegeManiac »