Anybody know what's up with my performance laptop?

Riaan-Combrink

Hi guys.

I've been struggling for two weeks now with the weirdest problem with the laptop I use on stage to play my backtracks through.

Its a really sturdy old-school HP notebook (circa 2004), and I've used it onstage off and on since then. Since 2007 almost weekly, so it it's a work-horse and mega reliable. Would hate to lose it.
http://h18000.www1.hp.com/products/quickspecs/11599_na/11599_na.html

I run XP (SP2), and use the machine only for stage. No internet or business apps. Play midi through Cakewalk / Sonar and mp3s through Itunes.

About two weeks ago, the laptop slipped as I took it out off the travel bag and sort of nudged the desk-top. I cushioned most of the blow, and it couldn't be described as a fall in the true sense. But still, my first thought was whoa - did it damage? When I connected it to my PA, I heard the weirdest thing. It can best be described as a whooshing, crunching sound - almost as if the working parts inside the laptop are being amplified (drive noise, creaking sounds, etc). Its really annoying. One can't hear it if a track is being played, but during a quiet intro or fade out - and obviously between tracks - its VERY noticeable (especially at gig volume). Muting that channel between every track is a major inconvenience and obviously disrupts the flow of performance.

Anybody have any idea? A very reputable laptop tech-type (recommended by two computer shops in my area) telephonically advised that the laptop may have gone "microphonic". I googled this (usually also mentioned in relation to amps), and it seemed plausible. Took it to the tech, who serviced machine and confirmed that she could find no fault whatsoever on the audio components and output. Cost me a whack of money and still the noise is there. >☹

I did all the standard diagnostics first. Changed laptop lead to another channel on mixer. Ditto. Changed the cable connecting laptop to mixer (same channel). Ditto. Used a different laptop with same and different cable to same and alternative channels on mixer - NO NOISE! So I appear to have eliminated the cable, mixer channel and mixer settings as potential causes. Also checked the obvious stuff - battery and disc drives not loose, etc.

Anybody have any ideas? I'm already a few hundred down and wary of walking up to the next guy who'll charge me the same amount and the problem may still persist. I even did a system restore to an earlier time to eliminate any possible software conflicts, etc (pretty pointless as nothing was loaded, but none the less!).

Any ideas about specific angles I may follow up, rather than just blindly asking someone new to look at it? Any advice would be greatly appreciated.

TomCat

What happens when you unplug the mains power to the laptop and run on battery only?

Warren

Can you try testing with an external audio device, like a USB external sound card? Just to try and isolate where the problem might be?

Bob-Dubery

Did you somehow turn on some kind of built in mic?

AlanRatcliffe

Ceramic caps can become microphonic, and it would have to be in the audio circuitry. It would probably be on the input side (probably mic input, which has a fair bit of gain). Try disabling or turning down the inputs in your software mixer (I presume you are not using them for anything anyway).

Otherwise, not much that can be done short of replacing the motherboard. Six years old is quite old for a hard working laptop, and after a knock you can never really rely on them for mission-critical stuff - other things tend to start going wrong in quick succession. It might be a bit difficult to find a motherboard for an older machine though and they tend to be expensive.

One way of sidestepping the repair issue is to disable the internal soundcard and use a USB or PCMCIA soundcard (although still no guarantee that other parts of the mobo won't start failing). If you get a reputable music brand interface (Edirol, M-Audio, ESI, etc.), you will probably find that your sound quality will improve drastically over what you had using the internal. Not expensive for what you need either - a line level only 2-in, 2-out like the Edirol UA-1.

Riaan-Combrink

Thanks, guys. I'll check for the microphone input and disable if possible.

An audio interface has been top of the 'next buy' list in any event for some time (for recording). May be the way to go as opposed to getting another laptop (small netbook or something). Will then get the dual benefit of being able to use to record (rarely) and use as performance soundcard (often). I have a better specced laptop that I was going to use for recording.

Now I see the 'sold" sign for the UA-25 in your springclean list. Aaarghh! >☹ I just remembered I have a very basic interface boxy (behringer :-[) that a buddy got with a mixer that I can use to test the basic concept. I also bought some nice gold-plated cables to go with the box when i got it (but lost interest after I couldn;t figure out how to record!).

PS: Will it then go into my laptop's usb slot, and then via RCA (x2) from the interface to (presumably) the line in (1/4") on the mixer (or do they come with XLR also)? Or to the RCA (tape?) ins on the mixer?

AlanRatcliffe

Most have RCA for consumer line level, 1/4" for pro line level and mostly only the bigger rack units have XLR. Use whatever matches best on the mixer (some mixers only use XLR for mic level, not line). Some of the 1/4" jack models use balanced TRS jacks so you can use balanced TRS to XLR cables. Tape ins are fine, but if you want to use any of the features on the channel strips (EQ, FX sends, inserts, etc.), you can just use RCA - jack cables.

Renesongs

It sounds to me like you have been very lucky for the last for years. All the internal sound cards I have tested on HP and other laptops intermittently go micro-phonic and start picking up the sound of the hard drive spinning up to speed the little clickity click of data being transferred etc. External USB sound cards are a necessity if you are doing mission critical stuff like live performance. Be careful what you buy though because even External sound cards can be pretty shoddy even some of the reputable brands.Best way to find out is to take your laptop to the store and test the interface before you buy. If they don't want to let you do that then they were probably trying to flog you rubbish. BTW I would recommend you upgrade your XP to SP3 or Windows 7 (runs like a dream on my old HP Aspire laptop ) and reinstall your sound drivers (search the net for new ones) this may solve your problems for a while.

Riaan-Combrink

Thanks, Alan and Rene. Will shout if I need more help!

Riaan-Combrink

TomCat wrote: What happens when you unplug the mains power to the laptop and run on battery only?

@ Tom: on battery, NO noise. Plug in the AC, it's all there, phishing, and fwaashhing away!

Would this then be something in the AC adapter itself that is faulty, or is it pointing to something else (that the laptop does with the current it receives)?

Renesongs

Doh - rule number one when using a laptop and sound external or internal : Remove the earth on the wall plug of the power supply. I sincerely hope that is not the answer because how you managed to get no noise before the incident would then become a complete mystery.

Riaan-Combrink

Renesongs wrote: Doh - rule number one when using a laptop and sound external or internal : Remove the earth on the wall plug of the power supply. I sincerely hope that is not the answer because how you managed to get no noise before the incident would then become a complete mystery.

Rene, I'm electronic illiterate. But the replacement I made when my power cable shorted just before the noise started, was to swop out the cable that was supplied by HP (with one of those two prong Euro-type things on - not the flat,cheapy ones, but the big round ones that you can't fit into any RSA-made multi-plug without cutting off the little lip on the round hole), and replace it with a clover cable that ends in a three point plug (from an electronics shop - Zakspeed, I think). Am I reading you right that the Euro-plug doesn't have an earth, and I've actually added an earth by using a normal three-point plug? :-\

AlanRatcliffe

Renesongs wrote: Doh - rule number one when using a laptop and sound external or internal : Remove the earth on the wall plug of the power supply. I sincerely hope that is not the answer because how you managed to get no noise before the incident would then become a complete mystery.

+1. Or D'Oh2. You didn't say anything about the power cable change!

Yup. From what you've said, sounds like you inadvertently lifted the earth with the old cable - which is what you need (it's earthed by the mixer when hooked up to the sound system). When you replaced the cable, you "fixed" it and added the Power supply's earth back into the equation, creating an earth loop. Disconnect the earth in the plug (if it's a moulded plug, cut it off and replace it) and all should be well again.

Riaan-Combrink

Alan Ratcliffe wrote: You didn't say anything about the power cable change!
Yup. From what you've said, sounds like you inadvertently lifted the earth with the old cable - which is what you need (it's earthed by the mixer when hooked up to the sound system). When you replaced the cable, you "fixed" it and added the Power supply's earth back into the equation, creating an earth loop. Disconnect the earth in the plug (if it's a moulded plug, cut it off and replace it) and all should be well again.

OK, just ran all my tests! This is definitely it. I installed ASIO4ALL (Jun 2010 version) onto the laptop and connected up the Behringer UCA200 interface. ASIO4ALL automatically made itself the default for both Itunes and Cakewalk. Scratched my head and figured out that the two RCA from the interface's "out" had to go to my mixer's "in". Oops, i only have one line in 1/4" slot on backtrack channel, but two 1/4" jacks needing to go into mixer. Ah-ha, channel 13/14, where the RCAs would go in, have a L and R 1/4" (just like you projected, Alan ?). In there, and brilliant. Fortunately its a nice mixer and I still have my 3-band roll-off EQ on the dual channels to the end.

Turned volume up, and the horrible sound is STILL there. Played two tracks (one mp3 through Itunes and 1 midi through Cakewalk) and the audio response was phenominally better than when I used to stick an instrument cable from the laptop out into the line in on the mixer. You guys were right - even on the crappy Behringer unit, the lows were tighter, sounds appeared in the mid-range I'm sure I hadn't heard before. Much better backtrack sound (x 1 000) 8). Can't wait to try some of the better interfaces.

And for the test. Stopped playback, and horrible noise still there. Unplugged mains from PC, and BOOM,everything quiet. Beautiful silence on battery only.

So that backs up the diagnosis. Earth loop. Now just have to Google to see whichwire inside the plug is the earth :-[.

For present purposes, the little UCA200 is already a huge improvement on playing through the internal soundcard.
http://www.free-instrumentals.com/behringeruca200.html

But I'm glad I bought some good RCA/1/4" cables at the last Bothner's sale - Proel Die-hard Gold-Line pro audio cables. They seem to do the job nicely. At 3m they're perhaps a bit unwieldy for the live set-up, but I'll figure that out. Next gig I'll definitely use this set-up.
http://diehard.proelgroup.com/diehard/en/product.jsp?id_prod=11099296328400&id_scat=11103895625210&id_cat=11103895626290

Now I'll try to figure out where to connect the interface's "ins" on the mixer, and give this recording lark a go again for at least one competition before the end of 2010. My Yamaha mixer has many more buses than the 1-bus behringer I struggled with, so should be able to do it this time. Now I also probably know why my recording laptop (which also has a three point plug stock fitted) gave me the same noise that discouraged me from recording). Probably also has earth connected. :?

So what a learning curve day, guys. Thanks! That'll teach me to be "too busy" for GFSA over the last few months!

Thanks again.

evolucian

IT Crowd: Is it plugged in?

Is the screen on?

'Ave you pushed the power button... the little button over there...

TomCat

Glad you got it sorted. I've never been a fan of Laptop sound cards. Going the USB/Audio Interface route is always better.

Turned out to be cheaper than a new Laptop..... ? ?

Renesongs

Rene, I'm electronic illiterate.

Don't beat yourself up about . I come from a family of engineers at least one Electrical and I did my first gig on stage with a laptop humming away through the PA fortunately a had the good sense to pull the power supply out of the laptop for the the second set. I was just flabbergasted that you hadn't had the problem right from the start. ???

AlanRatcliffe

Now just have to Google to see whichwire inside the plug is the earth :-[

Green/yellow. In a Standard 3-pin plug, it's the fat pin.

cain

It could be a number of things, best to open her up and have a quick look.

But ...

TBH at that age, i would just buy something new, considered a netbook? On raw power it should outperform your old notebook. Be more portable etc.

cain

Sorry, accidentally went to the first post, didnt see its been sorted ☹