Have I Blown it?

Howard Warehand · Post by **Howard Warehand** » 24 Jun 2015 12:32 am

For convenience I have been playing my lapsteel through my HP Compaq using an effects prog called GNUitar. The pickup is a single coil run direct to the computer line in.
This has been just fine until yesterday when I switched on the system and found no sound from the speakers except a high pitch buzz, this is constant with an occasional variation . Alternative speakers were tried but the buzz is still there. The PC functions OK otherwise.
I had a look at the onboard hardware manager which reports that there are no inputs connected.The headphone socket is dead except for the buzz too.
I am told that I have been pushing my luck with the standard sound card,have I fried it?
I would be grateful for any help please.
Howard

Charlie McDonald · Post by **Charlie McDonald** » 25 Jun 2015 3:32 am

This makes me very aware that I need that USB interface for recording to DAW. I've heard about frying soundcards. Yike.
Thanks for the heads-up, Howard, and I hope you get answers that account for the many variables.

Jack Stoner · Post by **Jack Stoner** » 25 Jun 2015 1:46 pm

I doubt that the guitar directly to the PC's input will fry it. In fact an "instrument level" is way below what the input is expecting. Its expecting more a "line level" signal.

Recycle the sound and see if that makes a difference. Go to the Device Manager, RIGHT click on the entry for your PC's sound card to highlight it (will be something such as Realtek, Conexant,) then LEFT click "Uninstall". DO NOT uninstall the drivers. Restart the PC and when Windows starts it will detect and reinstall the sound. See if this fixes it.

To access the Device Manager, Click on Start then RIGHT click "Computer" and then LEFT Click Properties. When the Panel comes up Device Manager can be accessed from the list at the upper left of the Panel.

Let me know if you need more info.

Dave Potter · Post by **Dave Potter** » 26 Jun 2015 4:36 am

Jack Stoner wrote:I doubt that the guitar directly to the PC's input will fry it. In fact an "instrument level" is way below what the input is expecting. Its expecting more a "line level" signal.

I had the same thought; a "line level" signal can be anything up to about 1 volt, and a guitar pickup, since it's unpowered, can't get anywhere near that.

Given that, I'm surprised it worked at all. But the symptoms are odd.

Charlie McDonald · Post by **Charlie McDonald** » 26 Jun 2015 4:56 am

What I find running direct through the audio port of my laptop is a lot of noise along with the signal.
A computer needs a USB interface to do the job right.

Howard Warehand · Post by **Howard Warehand** » 26 Jun 2015 8:30 am

Thanks to all for your input, it's a great help. OK , Jack, I tried your suggestion and as you predicted the system picked up the Realtek audio again when the system was rebooted.
Sadly still the same buzz. Here's what I have observed or fiddled with so far.
The buzz starts immediately the power is turned on and before Windows completes boot up.. The Speaker icon in the tool tray has a red X beside it but it the X comes and goes and when the mixer is displayed the sliders and "nothing connected" are displayed alternately but the buzz is not changed during this on,off mode. The HP trouble shooting system advises reinstall of the audio driver, this was done with no improvement .
So far I can't link this noise with anything in particular .
If you think of something to try, please let me know .
Howard

Jack Stoner · Post by **Jack Stoner** » 26 Jun 2015 10:48 am

This sounds like a hardware problem, but it was probably just coincidental with plugging the guitar in, assuming that is all you did is plug the guitar directly to the PC with no other devices connected.

For testing, check the BIOS and see if there is an option to disable the audio. If there is, disable it and see if that eliminates the buzzing at power on.

Howard Warehand · Post by **Howard Warehand** » 27 Jun 2015 9:46 am

Jack,
I have disabled all audio from the BIOS and the buzz still persists. I did notice that when power is applied and the speakers are active, the sound starts low, quickly climbs to a high level and then settles down to the constant note which is about middle "C" by the way. I'm coming around to your way of thinking that this fault coincidently arrived when I was using it for my lapsteel and was caused by some other "Force".
As this system (HP SG3-140UK Compaq) has a one piece board so the cost of the replacement may make me think about my options, it's unfortunate that the computer works just fine even if the sound system is on the blink.
So, Jack, what say you?? and I thank you for your interest in my problem , it is much appreciated . One last word from you and according to what you think I believe its time to draw a line under the event.
Kind Regards
Howard

Jack Stoner · Post by **Jack Stoner** » 27 Jun 2015 2:39 pm

This is a desktop system. If the sound on the motherboard is trashed, you could install a separate sound card and use that (assuming that is the only thing wrong).

Looking at the motherboard, there are two PCIe expansion slots, so a PCIe sound card would work.

Another option is a USB connected sound card, but my choice would be the PCIe.

Here is a listing for e-bay UK.
http://www.ebay.co.uk/sch/i.html?_nkw=pci-e+sound+card

Howard Warehand · Post by **Howard Warehand** » 1 Jul 2015 10:58 pm

Thanks, Jack, I'll give your suggestion a go.