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Écrit par : crazyoval ven. 4 janv. 2008, 20:17

Hi guys.

I've just got myself a 2nd hand dual 2.7Mhz G5 running 10.4 and 4Mb RAM. Ive upgraded from a G4.

I have an issue with the G5 in that there is a lot of background noise, when I turn the volume up its like a bleeping sound mixed with buzz and crackle as I move the mouse around the screen. I had this on a G4 Powerbook and I could only stop it when I disconnected the power, clearly an option I don't have on the G5.

Has anyone else experienced this and has got to a solution? Ive done a search for 'noise' but couldn't find anything else.

Thanks in advance....

Écrit par : leegrainge sam. 5 janv. 2008, 15:24

I also have had this issue in the past.

I worked out that (if you're using active speakers) if the 1/4 - XLR cables run too close to the computer then you will get these interferences.

You could try getting grounded cables, and or, you could buy a condenser (around 100£) The condenser will cancel out these unwanted noises. If you're using the built in sound card then that's a real issue, mine is awful in terms of noise, my external sound card is fine.

If I had more info on your specs then I might have more ideas.

Hope this helps.

Lee

Écrit par : lepetitmartien sam. 5 janv. 2008, 22:46

- You can try a SMU or motherboard reset (see the http://nav.440network.com/out.php?mmsc=forums&url=http://docs.info.apple.com/article.html?artnum=300341) according to your G5 model.

- You can install the CHUD tools from the developer's tools (on the OS X install DVD, or from Apple developer's connection site for the latest). With these there's a Processor system preference which allows you to disable the CPU "nap" ability. Try to. You'll have to set it this way each time you need a noise free recording as the settings disables itself at each system start up.

If neither option works… I don't know…

Écrit par : Mac Daddy dim. 6 janv. 2008, 08:13

crazyoval
(Hi guys.

I've just got myself a 2nd hand dual 2.7Mhz G5 running 10.4 and 4Mb RAM. Ive upgraded from a G4.

I have an issue with the G5 in that there is a lot of background noise, when I turn the volume up its like a bleeping sound mixed with buzz and crackle as I move the mouse around the screen. I had this on a G4 Powerbook and I could only stop it when I disconnected the power, clearly an option I don't have on the G5.

Has anyone else experienced this and has got to a solution? Ive done a search for 'noise' but couldn't find anything else.

Thanks in advance....)

Yo, crazyoval... You can put your computer in another room... Only hassle CD's/DVD's... The best solution is below... But, it is expensive... Probably take the money you saved on your G5...



Noren Acoustilock gCab Computer Cabinet

Paul White

Computer noise is a major problem in the computer-based studio, especially where instruments or vocals have to be recorded in the same room. This product is designed to tackle such noise, and is essentially a soundproof cabinet with in-built cooling system. It's designed to accommodate anything up to the height of a Mac G5. There's a little width to spare, but it's not much room for any external drives, unless you can stand them on edge next to the computer. A modern Firewire drive might also fit on top of a G5 at a pinch.

Noren's cooling technology uses rods with exceptional thermal conductivity. One end of the rod projects into the box with the heat source while the other is fan cooled in a separate chamber, which means that up to 800W of heat can be extracted without needing a direct air path.

Separate fans circulate air over both ends of the rods, and extract the warm air via an acoustically absorbent ducting system. Because of the width of the heat exchanger system and the thick foam cabinet linings, the cabinet ends up being a fairly bulky 26 x 24 x 32 inches, even though the computer section measures only 22.75 x 12 x 24 inches.

The cabinet is black (although Maple finish is also available at no extra cost) and built from laminated MDF. Doors to the front and rear, held closed by basic catches, are kept airtight with foam gaskets. The rear door's gasket is thick enough to allow cables to exit the box simply by being 'trapped' in the door. A sliding base allows the computer to be slid out if necessary.

Even without the castors supplied, the gCab was too tall to fit under my studio worksurface. However, having set it up to one side, its top provided useful extra workspace.

The specifications state that the noise level of a desktop G4 computer can be reduced from 61.5dBA to 37dBA in the gCab. Tested subjectively, I found the gCab to be virtually inaudible, even when listened to in a quiet room, which after all is what you need to know. Given the complexity of building and shipping a unit like this, the UK price seems pretty fair, though it still seems a lot to pay for keeping your computer quiet, as you could buy a halfway decent PC for the same price. Nevertheless, if you need a quiet environment and you have space to accommodate the gCab, it could make the difference between being able to record in the same room and not.

Published in SOS January 2005

Écrit par : leegrainge dim. 6 janv. 2008, 14:31

Mac Daddy. Although your second option is a great one, the price is a bit high for the general user. Your original option of "stick it another room" or at least at the other end of the room, I think, suites well.
Considering VGI or VGA cables are around £50 each, with a small expense of all the other long cables you might need, such as MIDI USB FIREWIRE ETC... you probably won't have to shell out the expense of having a cabinet.

Lepetitmartien. The SMU motherboard. Has that got anything to do with cable or mixer noise reduction?

Your choice crazyoval.

Écrit par : Mac Daddy lun. 7 janv. 2008, 06:41

leegrainge... I could not think of the names of the VGI or VGA Cables.

I always think Professional first when considering any purchase, I think it's a small price to invest for the millions I'll one day make... Though I'm beginning to wonder, maybe a couple hundred thousand????

The amount of anguish and daily suffering caused by Hummmmmmmmmmm is worth whatever it takes. I'd get the Cabin if I needed it... Actually, I want it, but can't afford it! I know several people with the VGI /VGA cables... They love it.

In closing, finally... leegrainge, you are 100% correct...

Écrit par : fictionmusic lun. 7 janv. 2008, 08:53

What you need to do is download and install CHUD tools from the apple site.


http://nav.440network.com/out.php?mmsc=forums&url=http://developer.apple.com/tools/download/

Once you do that you'll have a little icon on the top menu bar (by the date on the top right). If you click it a menu appears and at the bottom of it there is the line
"open hardware prefs"

click that and a window opens up. Under power there is a dialog box that says "nap"


click it and your noise issues should vanish.


Every time you restart you'll need to go back and turn off the nap function, but other than that you should be good to go. I use CHUD tools version 3.5 and not the later ones so if possible, I'd recommend you getting that.










here is a better link....

http://nav.440network.com/out.php?mmsc=forums&url=ftp://ftp.apple.com/developer/Tool_Chest/Testing_-_Debugging/Performance_tools/


I'd go with 3.52 release.

Écrit par : crazyoval lun. 7 janv. 2008, 15:18

HI guys, thank you for your support. I will check my xlr cables. Im also using an emagic 6\2 that came with Logic Gold. I intended to upgrade later last year. Now I have a G5 Im wondering about the fibre in and out so there's even less noise issue. Ive also got an analogue mixer which routes in audio and routes audio out to the active Tannoys.

So there's a few things I could do here, but none of this was an issue with my G4. I moved to a G5 because of speed issues and fan noise. I heard my mate's G5 and it sounded so quiet I felt it was worth the hassle upgrading.

Blime, Ive never heard of a CHUD before but thanks I will also give this a try since the G5 is the only thing that has changed and now Im getting a lot more noise.

Aa mate of mine uses a G5 for his studio and hes not had to do this. Perhaps a G5 is more sensitive than a G4 to radiation issues maybe...

Thanks for your support everyone

Guy

Écrit par : abcdaniel lun. 7 janv. 2008, 16:12

Just a note, there´s an older thread on this: http://en.440forums.com/forums/index.php?act=ST&f=6&t=21592
There is a somewhat useful link in there to an xlr8yrmac article. Chirping and weird noises are due to advanced power managment, especially when it comes to powering the graphics card, and strikingly poor hardware design for the power components in the G5.

Having a G5 myself, annoyed as hell at the chirping, I decided against disabling nap cause I was concerned with hardware longevity. I might be too cautious. My Mbox doesn't get get any of these interferences however, with the Mbox placed on the desk and the G5 below.

Hope it works out or you learn to cope!

Écrit par : crazyoval lun. 7 janv. 2008, 17:00

thank you abcdaniel, I shall look there too. My emagic 6/2 is on the desk too well away from the G5 but Ive not got yet to checking the XLRs. Ive re-routed and separated all audio and data devices to separate power supplies too.

Ive now read the other docs and it doesnt seem clear if nap will have any adverse effect on your G5 or not. I guess if you have to turn it off when you use it for sound only, it aint off all the time.

Ive just checked the nap button and it definately stops the churping sound. I still have some sound but I think I need to upgrade my audio device and mixer as well as check my XLR cables too.

Thanks all again, really appreciate your help.

Écrit par : fictionmusic mar. 8 janv. 2008, 07:30

I have been using CHUD tools and the nap thing for 5 years now with no adverse effects. I think that if you have the chirping (not all do by any means) then not disabling nap means that you'll get the noise into your audio output. I have used the Firewire 410, the RME Fireface 800 and 400 and they all let the chirping through so I had no choice but to disable nap.

I also have had my mac on for about 5 years now so I really don't think any hardware issue as far as longevity is really relevant. I have never had a single system crash (after the three I had switching sampling rates on the firewire 410 5 years ago; that was solved by updating the drivers....since then every thing has been rock solid) and I run a studio 24 hours a day.

This was a fairly known problem when the G5 came out, and everyone I have talked to about it reports flawless long-term use, so I really wouldn't worry about any hardware damage as a result of disabling nap.

Écrit par : crazyoval mar. 8 janv. 2008, 08:44

thanks fictionmusic, from the posts the other guys referred me to it did seem ambiguous. Since its something that you have to switch off each time you turn on the studio (assuming you turn off your studio which in you case seems not to be the case) I can turn it on when I need it.

Thanks for your advice. Wish I had done this with my powerbook nearly 5 years ago now.

Écrit par : leegrainge mar. 8 janv. 2008, 17:26

Mac Daddy, what a great sense of humour you have!
I only found out what they were called by joining another forum that only talks about such things
Best.
La Grainge (as my ancestors called it)