PC noise in scope/pulsar card

[aum7]

before i give up on this card and buy something else, i wanted to see if anyone else has this issue or if it can be solved?.........

i have a pulsar I, 4 DSP PCI card, V5 scope OS
Win 7 32 bit & Cubase 5

basically whats happening is that when my HDD is in use or i move my mouse, i hear a weird 'digital' type noise coming through the record bus of scope.
so anything i record has this noise on the track.

i have a mixer plugged into the analog IN's of the scope card.
if i disconnect the mixer the noise is still there, so the mixer is not the issue.

i have also tried the card in another PC and have the same problem.

when i contacted Scope support, they said its an inherent problem with pulsar cards and that i should use the ADAT connection. which isnt an option for me, nor is this a satisfactory response from Scope.

has anyone else experienced this problem or knows a way around it?

Thanks Scopers

[w_ellis]

Hi,

I'm afraid I've had exactly the same problem and I'm pretty sure it's to do with the quality of our electricity supply and general RF issues inside the PC. I bought myself a Behringer ADA8000 for around £100 and am now very happy.

Probably not the answer you're looking for, but I reckon it's cheaper (in time at least) that trying to debug electrical noise issues.

Thanks,
Will

[garyb]

there shouldn't be any significant noise from the mouse or hdd. what is sharing an irq with the Scope card, if anything? are you sure the motherboard is well grounded?

[the19thbear]

I have had the same issue. Its a power problem. The cards have a tendency to to Pick up noise easily... I solved it by NOT grounding the computer and grounding other studio stuff... I guess youll have to experiment.
.. Turned out the pc was "leaking" noise via the power gavle to alot of other audio equpiment.
The ulimate solution was to move All of my stuff to another location though.

But see if somebody Will lend you an adat interface, maybe that Will help.

Happy hunting!

[garyb]

the adat interface will reslove the ground loop, but not the problem. 19th bear is correct, a power supply with issues will make noise. actually, grounding in the studio is a serious thing, maybe even life threatening in some cases. but usually it's just not good for gear, especially stuff with ics.

i'd check the grounding in the computer itself first(not the wall, but inside the case. the wiring in the wall must be correct too, of course..). if you don't have a high quality power supply, i'd just replace it, if you do have one, there is software that monitors the voltages during operation. check it.

also, what about those irqs?

[dawman]

I had a similar issue w/ a mouse and other oddities and it turned out to be my APG 4x Matrox Video card. I didn't have these issues while it was just a Gigastudio DAW using an EGO-SYS WaMiRack. But adding my first Scope Pulsar card brought this trouble. The builder upgraded the card to a Matrox AGP 8x w/ 32MB's of RAM and this fixed the issue.
Wow I just realized how long ago that was....

[aum7]

thanks for the reply guys......

ive tried the card in 3 different PC's and in 3 different premises and all have the noise issue, so i doubt that 3 different PC's would have the same problems, wheather it be graphics cards or power supplies etc.....

the P/supply i am using now is a very good 750W supply.


Another bit of info i didnt mention before was that, 3 months ago i updated my PC, everything was replaced.
the noise WAS NOT present for the first 2 months of using this new PC.
then out of the blue it started again. NO changes were made to the PC hardware or software in this time.
go figure!

im not sure how to check the IRQ's though? the IRQ's would not change once set, so why would the problem start up again after a couple of months of use?

[aum7]

oh one more question..........

excuse my ignorance but what the hell is ADAT and is it an interface that i can connect my mixer to to get audio into the scope card?


And, if i bought a sound card thats connected externally via USB or Firewire will it resolve any earthing or grounding issues? or do i still risk having these probs?

cheers

[w_ellis]

http://en.wikipedia.org/wiki/ADAT_Lightpipe

It's a multi-channel digital audio transport, that uses toslink optical cables. Various devices support ADAT to analog (in both directions) conversion, including the ADA8000 I mentioned above and the A16 Ultra (which is a lot more expensive).

You will probably be able to get a USB/FW sound card that will get rid of your noise issues, but using it with your Scope card might not be as straightforward as you're thinking. Routing audio within a PC is typically a bit annoying and almost always introduces latency.

Thanks,
Will

[aum7]

OK, i found that my video card and scope card share the same IRQ 16.

can i change this? and what would i change it to?

[garyb]

yes, firewire and usb are also prey to grounding issues, but i don't think that that is your problem.

ahhh, the old video shared irq. it doesn't always make trouble, but when it does the trouble looks like yours...

the best thing would be to move to another slot. when you do that, tell me what the card is sharing with, and i'll tell you how to eliminate the shared irq all together(assuming that you get another shgared irq).

[aum7]

hey gary,

i moved the video card to another slot and the problem is still there
they still share the same IRQ 16.

i cant move the scope card cause i have a X58UD7 MB and it only has 1 PCI slot.

any other suggestions mate?

thanks

[CroNiX]

Google how to change IRQ for your particular OS version. Most likely it will involve disabling ACPI, which in later OS's is responsible for IRQ assignment. With ACPI enabled, the OS makes the decisions on IRQ assignment and you can't change it. With it disabled, you can, although its also possible to lose some functionality of your PC (like being able to shut it off from windows start button or from other software...it will start shutting down and at the end you get a message that its now safe to shut off your pc instead of it doing it for you).

[garyb]

bad news.
i would consider a different motherboard. the cost will likely be less than a new sound card...