[sparrows78]

This soundcard sounds really great, but after a while I noticed a slight noise coming from the right channel. It's only in right channel and only from Front Out. The noise is always present - even with all volumes turned all the way down. I have tried all obvious things, like changing the cord/headphones/speakers etc. - I even replaced the opamp - without succes. It sound like some kind of interference - what do you guys think?

A recording can be found here:
brus2.wma

Please take a second to listen and give me a thought of what you think might be the problem!
I'm grateful for all help!

 

[infinitesymphony]

If you can, try moving the card to a different PCI slot; it may be picking up EMI from other components in the computer. Could you post the sample as a MP3? That will make it easier to decode in order to view the waveform.

 

[sparrows78]

Quote:

Originally Posted by infinitesymphony /img/forum/go_quote.gif If you can, try moving the card to a different PCI slot; it may be picking up EMI from other components in the computer. Could you post the sample as a MP3? That will make it easier to decode in order to view the waveform.

I have tried it in all PCI slots, still the same noise - my first thought was also about EMI, too bad its hard to experiment inside a small computer.
I'll repost it as mp3:
http://www.mediafire.com/?biuefbjn2im

 

[RoosterX]

I am curious how did you record this, using your auzentech line out -> line in?

I would if possible try the card in a different computer if it's the same problem there you have saved yourself a lot of trouble and just RMA the card..

 

[infinitesymphony]

After normalizing it in an audio editor, I see that the left channel is white noise (probably the overall noise floor of the card+computer), but the right channel is filled with static. The static itself appears to have a positive offset. I also hear a 50 Hz tone, which reveals a potential electrical ground loop problem (and also means that you aren't in America

). Are all of your devices plugged into the same outlet / circuit?

 

[sparrows78]

Quote:

Originally Posted by infinitesymphony /img/forum/go_quote.gif After normalizing it in an audio editor, I see that the left channel is white noise (probably the overall noise floor of the card+computer), but the right channel is filled with static. The static itself appears to have a positive offset. I also hear a 50 Hz tone, which reveals a potential electrical ground loop problem (and also means that you aren't in America ). Are all of your devices plugged into the same outlet / circuit?

Man I'm really grateful for the work you put into this! You say the static itself appears to have a positive offset, what does that actually mean?
And you are right btw - I dont live in the States - I live in Sweden!

But its' very rare with grounding problems here. I have two outlets in my apartment - the noise is present with both. But maybe I should look over the grounding here.

 

[infinitesymphony]

A positive offset means that the waveform is centered around a point above 0... Think of a sine wave that alternates between +10 and -2 instead of +6 and -6; the former is centered around +4 while the latter is centered around 0. The fact that the static is positive may mean that the device causing the problem (the sound card itself, motherboard, PSU, etc.) isn't properly filtering the power.

Ground loop problems occur due to differing ground potentials when parts of the same audio system are plugged into different circuits. The ensuing 'loop' is audible as a hum at your mains frequency (50 Hz in your case). This would explain the slight 50 Hz content in the sample you provided, but it's very faint; normal ground loop hum would be loud enough drown out the static--this means that the hum is only a secondary problem.

My guess at this point is that it's hardware-related. What kind of motherboard and PSU are you using? If you can, try testing the Prelude in another computer to be 100% sure that it isn't the card.

 

[Gollie]

I had to dig up this thread and repost because I am getting this same issue. I went through my whole set up and isolated the floor noise that i'm getting in my right channel only.

For note: swapped my output tubes, swapped to a cheapo Monster RCA cable, tried RCA cables in Amp only. All options yielded a dead silent floor.

When I unplug my Firemine from my DAC, I get a silent floor. When I unplug my Firemine from the card, the hum goes away also. The noise is definitely coming from the card.

This sux because I just upgraded from a Creative brand X-Fi Fatality and I don't remember having this issue.

Is there anyway to eliminate electric noise inside the PC?

 

[Diesp]

Quote:

Originally Posted by Gollie /img/forum/go_quote.gif Is there anyway to eliminate electric noise inside the PC?

Building an electric shield for the card ? Some of them have one, we should be able to build one ourselves.

If anyone has info on this it could be useful.

 

[Ricey20]

I used to get random static through my prelude too. I read that a lot were having this same problem and its centered around either the drivers or motherboard. Driver wise was mostly Creative's fault but even the Prelude uses creative's drivers as a foundation.

What version of windows do you use and what mobo? Also does it happen in every single mode? (gaming, entertainment, creation)