Hey guys (and girls), this is my first post here, and already I'm in need of help!
I have a compaq armada laptop PIII 700mhz with a built in ESS Maestro Sound Card, and when running this through a mixer and amp, there is background noise that is clearly audible in quiet bits of songs. It seemed to be related to hard drive activity and moving the mouse. I bought yesterday a Hercules Muse Pocket USB Sound Card (Nice and Shiny), expecting the problem to have disappeared, but I can still hear the background noise. Any ideas as to what may be causing this or what I could do to get around this?

Thanks for your help!

James

Always difficult to sort out these problems, and it really has to be done by elimination, or better still, a Laptop Technician. However here are some DIY tips to try and clear it up.

Is your laptop running from the mains, if so try it from its battery pack and see if it solves the problem.

Ensure that all audio leads, are kept clear from mains leads, and especially far away from the laptop PSU.

I get the feeling that something may be in the process of failing within you Hard Drive. It could be that the motor drive supression has failed in the HDD Motor / drive circuitry, or that you HD is about to fail completely. This would be my diagnosis, should the problem only started to occur recently, and non of the above solutions work.

I've emailed this question on to a collague of mine who does laptop repairs and servicing, to see what he suggests, and will post his reply as soon as I get it.

Welcome to the forum, by the way

thank you for your quick reply chris, I hope that you are wrong with the hard drive failing though otherwise I'll have to start saving my pennies! I'll do the smart thing and backup everything on here though should the worst happen. I've only really started dj-ing and only got my mixer and amp last week, so I wouldnt be able to tell you if this has been happening before I'll try the things you have suggested and get back to you!
I look forward to your reply and thankyou for your help!

James

[EDIT] Problem solved, it seems that when the laptop is plugged in to the power supply the interference is happening, Is there anything I can have done to the power supply to stop this, as I cant see my laptop batteries holding out for a whole gig!

Greetings James, my primary answer to this when I saw the title, (un)fortunately has already been covered by Chris. I too was going to ask if the problem is audible when the laptop is on its mains power, as well as when its running on battery. EG: Some mains adaptors "give off" some bad vibes (well, Electromagnetic interference actually).

However, one extra thing to try - although its going to sound (?) stupid.

Does the problem sound worse if using one of the larger, brighter, whiter (even animated) mouse pointers, and does it sound better if you use a really insignificant (almost invisible), low contrast mouse pointer. Some of my previous limited experiences of laptops and audio linking to larger sound systems has been that the more thats happening on screen, and the brighter, more active that "something" is, the worse the noise being passed out to the mixer.

One other thing which concerned me a little ...well lots actually was something that you said in your reply to Chris above.

Yes, very often problems with Audio and Laptops can be attributed to their PSU however unlikely the problem may seem to be related to Power!. Sadly laptop manufacturers tend not to make their products P.A equipment friendly, and the Power Unit is often where any cost savings are made, so they have little or no interference suppression .

Laptops use Switching Power supplies, which means that inside the unit there are components switching on and off 50 times per second, which causes interference, both in the power, and radiated from inside the unit similar to radio waves. The wires used to carry audio, and the components inside you mixer, amp etc can act like antenna's for these waves, and pick it up and amplify it - hence where your problem is occuring (& this is also why they don't allow laptops to be used on planes!!)

There are things you can do to try and stop it

(1) Position your Laptop PSU as far away from the Audio Equipment as possible, and don't allow any audio leads to pass close to it. Even try and plug it into another socket if possible, and NOT in the same multiway adaptor as your Mixer and Amp is plugged into!

(2) Consider buying a filtered mains adaptor / plug top for your laptop PSU. These cost around £15 on the high street and have about a 50/50 chance of working. Belkin are the most effective ones to look out for. Again, only use the filtered socket for the Laptop only, sharing it with your Amp & mixer would defeat the object!.

If 2 and 3 don't solve your problem, then its time to replace the PSU. However this is still a cheaper option than a new HD, it may simply be that the PSU is badly designed, or there may be component failure, or a capacitor dryed out inside it, either way the only way for you to solve it is to replace it.

Most laptops operate using the same voltage, current etc, so it shouldn't be too difficult to find a generic which works, if you can't obtain an original part, but DO double check the spec is equal to or better than the original before parting with your money.

no need to worry, my laptop has windows 2000, trial versions of OTS, PCDJ, visual discomix etc. and about 5gb of music, and thats pretty much it. Its not used for general stuff, only dj-ing. The mouse pointers dont seem to make any difference but thankyou for your suggestion. I'm going to invest in another battery, as my laptop can take 3, this should give me around 6 hours of battery life which should do for most gigs. I've had the power supply plugged in to its own socket, away from any other cables, and it still causes interference. Is there anything you know of that will stop this? would it be worth me getting another power supply?

thanks for your help

James

I supposed that wrapping the PSU in a nice thick sheet of Superman-proof Lead sheet wouldn't help would it?

I think everyone who has a laptop that isnt a Panasonic has had this trouble, I can't say how I got around it because it involves taking the earth off and fitting a RCD but as it is not recommended I cannot tell you this !

I think we'll leave the disassembling of PSU's to the professionals then!
The power supply i'm using now is a medion one which does the trick, no interference at all. Shame I cant keep it though so i'll have to go out and spend some more hard earned cash!

Actually it may not be the design of the PSU thats at fault. Components in circuitry can fail easily, and commonly the main smoothing capacitor in PSU's can "dry out", this means that the capacitance (Storage of charge) level can fall and ultimately interference can pass through.

If you are skilled in electronics, you may be able to repair it for a few £ but unless you know what you are doing then stay well clear and just buy a new one. Replacing the smoothing capacitors may well solve the problem but it's still a gamble and one that it would be worth doing only if you were good with a soldering iron, had the correct desoldering tools and can obtain spares.

At least you've now confirmed that it is the PSU at fault, all you need to do is to bite the bullet and buy a new one.

This used to happen with my Laptop , my problem was caused by the Mixer , it was an un earthed type , adding an an earth lead to metal case of the mixer stopped all the power supply buzzing and mouse movment noises.

I have since changed mixers to a Soundlab Fusion as supplied by Chris P and this mixer does not have any laptop noise problems for me.

I also now use a Soundblaster MP3+ external USB soundcard, which has realy improved the sound quality from the laptop.

When i was using a laptop i too had power supply interfearance. Fortunately, plugging it in to a totally seperate socket from the amp and mixer fixed the issue.

I'm very pleased i did not have to resort to dismantling power supplies etc as having found out the hard way over the years, i have a healthy respect for mains electricity !

Ian Stuart

I am now using a Hercules Pocket GameSurround, the sound quality is much much better than the integrated sound card. Anyone used these before? care to share your opinions?
I was going to get a Soundblaster MP3+ But I thought that the 5.1 Surround sound could come in useful one day!

Alot of Dell Laptops old and new seem to generate this noise which has an earthed mains supply to PSU When the earth is disconnected the noise stops but you should not leave the earth off.
My own laptop (Fujistu) is suppled with a PSU without any problem but I notive theirs does not come with an earthed pSU only live and net

Whats is an MP3 Soundblaster?
Any more info on these ?

Thanks for the link
Did you notice a difference using this then?
Is it the external sound card that improves the sound of MP3's or the bundled software that comes with it?

Dudes and Gurlz,

I don't no if the problem is fixed, but is it the audio file???
Sum CD's or Download Music can get background noises.
Try cleaning the audio files that do it, because if it happens only some of the time, then it not likely a power problem.

Remember when ripping to rip at the highest posible quality, regardless of the size!
If it sound good at the start, then you don't need to EQ much, and yes you should EQ pc's because here is no such thing as the perfect sound card.

Adrian

AND ANOTHER THING!!!!!!!!!!!!!!!!!

DON'T REMOVE THE EARTH FROM A LABTOP IF IT HAS ONE!!!!!!!!!!!!!

IF THATS WHAT YOU WANT RING THE MAKER AND ASK IF IT IS OK, BECAUSE SOME LABTOPS NEED THEM SO THEY DON'T BLOW UP!!!

AND GET A QUILIFIED SPARKIE TO DO IT, BECAUSE IF IT BLOWS UP AND HURTS SOME ON, YOU WILL TAKE THE FALL!

I used to have problems with my sound card.

My problem I found was stopped by adjusting the volume controls within Windows. By only having the 2 I need (Master and WAVE) this stopped all problems.

If I want to use the CD drive, I just simply un-mute it and use it. The same applies for anything else.