[Dorito123]

I am looking to buy a new amp and I mainly use a computer as a source. So I was looking at the manual for the new MF X-CANv8 and I noticed a passage at the end of the manual and I applied this wisdom to my own rig and I have to say that is works. I had been bothered lately by some slight noise and sometimes noise from other programs comming through my system. I had my dac pluged into a USB Hub with three other devices. I then moved the USB dac to a port on the computer and removed the other device on that channel to the hub. IT WORKS!!! Here is the passage from the XCAN manual.

Please note:
This device is a high speed serial data processor, and by its nature, requires a very high volume of USB bandwidth. It will benefit greatly from being the only device connected on its USB ‘bus’. Sharing the same bus with other devices may cause unwanted artefact's such as dropouts or temporary loss of signal. This especially includes the use of the X-CAN V8 on a USB hub/splitter alongside other USB components

 

[soundfreq]

would it matter if the hub is powered externally?

 

[Dorito123]

Mine was, I don't think that is what they are getting at, I think its a matter of sharing bandwidth with other devices. Usually USB ports come in sets of 2 on your computer. 2 channels = 4 ports. I left one channel devoid of devices except my Dac and that made a noticeable improvement.

 

[warrior05]

Hmm... I find this interesting. I wonder if it would solve the occasional drop in signal I get with my MiniDAC. The USB controller on my mobo crapped out so I had to buy a 4 port card. All of those are being used plus one of them is feeding a hub. I could get a 2 port card and just have the MiniDAC plugged into that. May be worth giving it a try.

Thanks for the heads up!

 

[sejarzo]

Quote:

Originally Posted by Dorito123 /img/forum/go_quote.gif ... I had been bothered lately by some slight noise and sometimes noise from other programs comming through my system. I had my dac pluged into a USB Hub with three other devices. ...

Just curious, what sort of noise? Did you have clicks or dropout issues?

When you mention noise from other programs......I never noticed that on a USB device, but my onboard ConexantHD sound device on my notebook always seems to have some very low and varying levels of static coupled with faint beeping noises at times.

I often find comments on home recording forums that folks using USB interfaces generally have a hardware setup that eliminates every other USB device possible, all networking is disabled, and unnecessary drivers are not loaded to avoid any possible glitches on the bus.

 

[Gaara]

One strange thing that I noticed using a USB Dac is that even using a USB device like a mouse adds noise. When I move the mouse around i can hear a little bit of staticy noise that is reproduced through my system. It isn't loud and is only noticeable if I listen for it with nothing else playing.

When I used a different mouse with one of the regular ports instead of USB the noise wasn't there. I can only imagine how other devices add their own sort of noise.

 

[Dorito123]

I noticed random noise (buzzing) and also I noticed music or speech which I assumed was from another program ie: IE 7 open and watching a video clip. I guess its possible that came from a cell phone but the voices and or music? I was becoming disappointed in my equipment and when I moved the cable last night I was so happy, it was like having my old (new) system back.

 

[slowth]

I'm also experiencing some sorta noise.. I don't even know what it is.. it's just like everything cracks up.. It doesn't seem to be my speakers cos when I plug in my music without the DAC it works fine..

What could it be? I don't think it's a usb issue either..

 

[Dorito123]

Give the usb thing a try, cant hurt.

 

[slowth]

ok! i'll take your word on it!

 

[mchang]

I had extreme buzzing with my Mac Mini > USB/Firewire Hub + hard drive > USB > EMU 0404 USB > Darkvoice 332. Same thing with Pico instead of 0404. Only fix was to use optical toslink to 0404, which eliminates use of Pico.

I'll have to try what you're suggesting. Thanks!

 

[sejarzo]

Ummm, guys, ever hear of the term "RT?M" ???

Page 48 of the E-MU 0404 USB owner's manual....under the heading "Pops & Crackles" , no less:

"USB hubs can create problems with digital audio and should be avoided whenever possible."

 

[jilgiljongiljing]

Yes the manual clearly states to connect directly to the computer to prevent pop and crackles. I think I mentioned in in one of my posts earlier as well.

 

[mchang]

I just remembered... strangely enough, I had no such buzzing problems with 0404 USB with CanAmp or GLite.

It's possible that I was using an onboard USB at the time. And just unknowningly switched to hub with DV.

Oh, and what's a manual?

 

[sejarzo]

If it's buzzing, that seems as if it's a ground loop.....you should try to connect everything in your playback chain to the same power strip.

I couldn't understand why I had a problem when first connecting my 0404 USB outputs into my speaker rig, until I realized that the HT receiver, the LFE output of which was connected into my Outlaw ICBM sub xover, was on a different circuit....and apparently modulating the signal ground on the xover.