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i have a pulsar II on a pc. i get a low level mid/high frequency noise from the analog outputs, like the interference you pick up when a radio is placed near a computer. this noise is affected by mouse movements, and by performing windows operations - sometimes the noise stops altogether, for example when i start recording in sound forge.

also if i move my mouse while running cubase 5 (recently installed), i get unpleasant sounding clicks and pops. it's fine as long as i dont move my mouse. these noises do not appear anywhere on the level meters of the cubase mixers. i went to look at the pulsar bigmixer to see if these clicks and pops appeared on the levels there, but when i switch to the pulsar window cubase stops making any noise at all. ???

Hiya bud:

Have you got a USB mouse? I used to have my trackball on one of my USB ports but had to replace it on the PS/2 port to kill the nasty noise, (really apparent from my badly designed Terratec EWS64 ISA card). I don't know any reason why USB would be particularly noisy...

yeah i have a usb mouse...that solution occurred to me. the interference noise still happens when i unplug the mouse though. maybe the mouse driver is creating the prob? but radio style interference sounds like a hardware thing to me. could it be that there is some kind of ground loop somewhere? i don't know enough about the guts of computers to know if that's possible.

maybe i should try a serial mouse .

what about cubase not working when i switch to pulsar window?

Easy one first: have you got both audio and midi setup to play in the background? They're not both enabled by default, so you could lose all sound or just your audio tracks when you flip to another application, (I can't remember if it's just audio that's disabled... hence being vague).

Are there two types of noise, a high-pitched continuous one and something that sounds like a zipper when you move the mouse?

I was only talking about the noise that occured when you moved the mouse - I reckon that'll be the USB. (By the by, I've disabled USB completely: I haven't got any USB devices - save the trackball - and the USB interface wants an IRQ. Bad for timing! See 'Hints & Tips')

The other noise is probably the electromgnetic interference ubiquitous in soundcards which have their analogue output stages within a computer's box. I think this comes off the CPU and the data busses, and I don't think there's any way to completely eliminate it. (I've heard of people wrapping their cards in tin foil ... that'd scare the shit out of me - shorts galore!).

Dunno why it's affected by windows opening / mouse movements, but I've heard this with my own ears before... A window opening would presumably send a whole load of data (possibly generating a load of noise) to your graphics card. Perhaps the noise would be worse if you had a PCI graphics card than if you had an AGP device.

A way of getting around this box-noise is to get your digital to analogue converter's out of and away from your computer. I use a Fostex VC-8 on one of the ADAT interfaces - that's a box with a 8 analogue inputs and 8 analogue outs. I only use two of the outs (stereo to my monitoring sys) but all of the inputs (from outboard synths). Gonna put a headphone amp on the outputs too as soon as I get around to building one.

<font size=-1>[ This Message was edited by: Sam Glass on 2001-07-18 06:05 ]</font>

<font size=-1>[ This Message was edited by: Sam Glass on 2001-07-19 01:57 ]</font>

no the noise is not really continuous at all, it changes depending what the computer is doing. like you can hear the cogs going round if it was clockwork...and it completely disappears as soon as i start recording in sound forge, which suggests to me it can be got rid of.

i would just think it was the natural way of things if i hadn't heard how comparitively quiet friends' pulsars sound.

woops just read your message more carefully, you did mention the changing nature of the noise, sorry. thanks for the cubase tip tho, i'm sure that's it.

By the way did you check the ac/dc adaptor? Most of the computers are equipped with a lousy one...

I find the analog outputs from my Pulsar II quite noisy even though I have a low noise PSU for my PC. So I use dont use them and always IO using my Fostex VC-8

N.

well the noise is either radiation(poor shielding)or a ground problem.my card is relatively quiet.every system has SOME noise problem, but it shouldn't be distracting.if it's unworkable then a solution must exist.(maybe a different ps or case,maybe a wiring problem in the building...........)wish i could give you real help tho....

I've noticed the silence when the computer's doing something computationally intense too. I used to use a software CPU cooler which, when there weren't any instructions to solve, sent some code to the processor which "turned it off" (I dunno), reducing the power consumption and hence the heat produced. That was *really* fkng noisy.

Now I don't have it installed, but if I listen to "silence" I can hear the change in intensity in box noise wih change in workload. The noise is mainly coming from my EWS card mentioned above, but is also coming into the Fostex box on my synth interconnects! This means either that the shielding on my case is shite, (very possible - my radio doesn't like my computer one bit), or the computer's putting interference on the electrical ground as suggested by Gary.

One day I'll buy an all-aluminium case and some proper power supply equipment, but at the moment my prob ain't too big You can't hear it often, and Cool Edit's noise-reduction feature gets rid of it a treat.

Scuse the ramble but I'm at work

Has anyone successfully used ferrites to reduce noise on mains cables?

I noticed that even the high-quality mains cleaning inductor advertised here under Earth Henry only blocks noise appreciably above 100kHz. I guess any noise that is audiable to my club blown ears is going to be substantially lower in frequency than this...

my ears are fucked too!! haha!

anyway, my initial feelings were that i have some kind of grounding prob actually. that would explain why the interference sounds like what you pick up with a radio, because there is a ground loop (ie radio circuit) in the pc somewhere...?? yes?

My setup have just about the same problem, namely the high almost rattling noise when the PC is idling (no noise during device-load or similar action).

I have come to the conclusion, that the noise derives from either my analog I/O cables acting like antennas and picking up digital noise from the PC or the fact that the A/D conversion on my Pulsar I (and yours too, I guess )is taking place just inside the box where it is exposed to digital noise in a major way.

Why there is no noise when the PC is working beats me.

I can confirm that ferite rings will do you no good in the audible freqs, no matter how little time you spend in the most silent club The ring that is already there is supposed to work on the SP/DIF's.

That was my $0,00002, anybody else ?

Cheers
Stubbe

I have no noise at all. The Pulsar is the most quiet synth/card I ever heard. I wonder what's up with yours:-) I use the Pulsar 2 plus which as balanced XLR ins/outs so if you're using unbalanced that might be the problem... I'll never buy a soundcard with unbalanced IO again.