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I had my system cranked right up the other day and I noticed that there was quite a lot of computer noise (buzzing etc. (this noise stops if I grab a software fader with the mouse)) coming from my Pulsar II board.

The only way that I can see to find out how 'normal' this noise is, is to test the signal to noise ratio of the card.

This is where I fall down!

Does anyone know the best/easyest way to test the signal to noise ratio?

Any help would be great.

Cheers guys/gals

Are you using an optical mouse by any chance?
Got any virus protection or firewall software running in the background? Which OS are you using?

Have you checked your ground connections? Noted any ground loop hum at all in addition to the mouse noise?

This "mouse" problem has been reported many times both here and at the old CW forum. I'm not sure I ever read any response that definitively isolated the cause. I suspect you have a grounding problem - or perhaps a software issue or both. Do a search here and see. There may have been some OS tweaks reported a while ago in response to this.

as Krizrox already wrote: it has nothing to do with the signal to noise ratio of the card.
Your problem can be influenced by interupts, but it's more likely related to the powersupply. The accellerator chip on the graph card draws a lot of current when active - it's getting pretty hot, so it has to

You should be able to increase the noise (or at least modify it) by moving windows around on the screen. Try with nothing connected to the analog ins and pulling the mixer up full throttle. If anything on the screen gets updated this should be reflected in the noise.

I had the same problem and I remember something around -60 dB on the meters for an empty analog input. Since I've exchanged the PSU I have -85dB.
My case is an extreme example because the original PSU was a tiny 90 Watt thingy in a small office box with an all-in-one mobo.

cheers, Tom

XP
P4 2gig
512mb Rambus
ASUS P4TE Mobo

There are my stats!

I am using an optical mouse, and this does change the noise as you click and drag a window around the screen. Infact the noise just about dissapears whilst dragging the window.

The noise is apparent without even having the Analog I/P connected.

Ihave had the Pulsar O/P Connected directly to the amp; thus removing the possibility of it being any form of hardware cable problem (I was also using the computer in my post production studio (in down time for music) and the noise was there also).

I have got a silent PSU in the computer (great for ambient noise - you dont even know that the computer is turned on) which I have a feeling may be causing the problem. I can't remember its power o/p at the mo though.

The only reason I was talking about signal to noise is that I would like to know just how loud this noise is....

Anyway, more tips are always apreciated.

Laterz

Your hardware is similar to mine. The biggest difference is your OS (I'm using WinME).

But I remember experiencing the same problem about a year or so ago (in addition to what I believed was a ground loop problem). I tried every possible "fix" known to man including, but not limited to:

1) replacing the mobo, processor & RAM
2) replacing the monitor (with a flat LCD model)
3) replacing the PS two or three times (now using a 400W silent model)
4) replacing the tower case with an industrial-style rack-mount case
5) dressing the wiring inside the case in such a way that everything was out of the way and neat
6) using rounded IDE cables on my drives
7) tweaking the OS (tried every possible tweak known to man)

Tried a Furman balanced power supply (this was an expensive and very heavy unit that I bought from and ultimately returned to Musician's Friend)
9) I may have tried a regular (non-optical) mouse at one point and that didn't resolve the problem either
10) Partitioning my hard drive so I could have a separate OS for recording and another for general purpose (internet) work.

I literally broke my entire studio down to a few pieces (PC, monitor, mouse, keyboard, mixer) and moved it to other locations in my house. We didn't use the dining room table for about a week while I was poking around at the guts of my PC. I had make-shift ground wires running from the PC to the sink in the kitchen and other parts of the house. It was a trip man, let me tell you. I spent hours scouring the internet looking for any reference material I could find on the subject of PC audio noise. I can tell you there is a lot of voodoo out there. In fact I think I actually hired a witchdoctor to come dance around the table at one point. I was willing to try anything

After beating my head against the wall for about a month or so, most of my noise problems seemed to disappear when I:

1) Bought and installed an A16 Ultra
2) Used the Firewire interface instead of the ADAT optical interface
3) installed some Ebtech hum eliminators between my PC and my mixer

Those last 3 items reduced my noise floor to practically nothing and I considered my problem resolved. These were guerilla tactics to be sure. All I can say is good luck!


PS: that little red happy face you see above is the result of trying to type "8" and the ")" character together. I guess this BBS must think I'm trying to be funny. I'm not.

<font size=-1>[ This Message was edited by: krizrox on 2003-10-07 15:02 ]</font>

Hi mgranger,

The power supply could still be the noise culprit in your system. The noise you described as coming from your Creamware card appears to be induced noise (i.e. electrical noise) which can result if not all is well in your system. The noise which your power supply is most likely designed to reduce is acoustical noise. The only way acoustical noise should affect your Creamware s/n ratio is if you mic' it and it somehow gets into your mix.

So, how many watts is your power supply rated for? 500 watts is good, 400 watts should do, anything less, get suspicious.

you can perform (loopback) signal-to-noise analysis and loads of other interesting figures using the free program RightMark

A good while ago, I performed a test of my Creamware Pulsar 2 and and my Fostex VC-8 ADAT I/O for a Dutch synth forum. Both interfaces performed surprisingly well! Take a look to see what RightMark can do for you......

<font size=-1>[ This Message was edited by: ernest@303.nu on 2003-10-07 19:39 ]</font>

Thanx guys

I shall try all these options in due time.

I think my PSU is a silent 350w jobby, so I think I will try out a 500w one and go from there.

It will be interesting to see whether the noise is purely from the analog outs or the ADAT o/p also.

I should be getting an Alesis 8in/8out ADAT unit soon, so should be able to test this.

Anyway thanx again guys - back to the music grindstone untill some more cash comes in now!!