AUDIOBOX USB Hummmmmm

  • Thread starter Thread starter Kip Carter
  • Start date Start date
Yes that is nasty, not really a hum more your buzz.

In fact it is what us old radio jocks' used to call a "griddy" hum and generally indicates an earth or screen open circuit somewhere.

From you later description Kip, that it increased as you approached the kit, I, like you, though of RFI and a buzz would indicate TV rf but that would give you a strong 50Hz field component.

You need to narrow this down as exiting a specific piece of kit and than get that looked at. Do try the whole rig out on another computer.

Dave.
 

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As a matter of fact I did that last night in another process of examining the DAW I'm using. I downloaded the eval of Reaper. I did this on my desktop in my office/studio and simply unplugged the USB cable from the laptop and plugged it into the desktops USB interface. Of course my next set was to test out the functionality of Reaper and so in that process (successful by the way) I was able to confirm that the hum is independent of the laptop. Same hum. Same intensity level (not greater or less).

Now my next step I'm going to consider is that the power sources are distributed across two different outlets. So I was planning on consolidating all the power source to one outlet on a strip so that I avoid any potential ground differential. I"m not optimistic that this will resolve it but figured it might be a worthwhile test.

Your thoughts?

Regards,
Kip...
 
Kip. Do you have lights in that room that are on dimmers by any chance?
 
mdainsd said:
Kip. Do you have lights in that room that are on dimmers by any chance?
Click to expand...

No but now that you mention it I do have some compact florescent lights in the room. I know standard fluorescents will at times throw RF. I'll add that to my testing sequences and report.

Regards,
Kip...
 
Kip Carter said:
No but now that you mention it I do have some compact florescent lights in the room. I know standard fluorescents will at times throw RF. I'll add that to my testing sequences and report.

Regards,
Kip...
Click to expand...

Ok but I think you have a faulty interface. Lights can radiate crap (but are MUCH better theses days) but with no inputs connected it is hard to see how it could get in?

Duff internal switch mode PSU is my bet.

Dave.
 
I've disconnected all inputs it affects the level somewhat (marginal at best). And ...
ecc83 said:
Duff internal switch mode PSU is my bet.
Click to expand...

Think I had one when I was a kid but the left wheel fell off! WHAT???? lol.
Regards,
Kip...
 
Ah well the power source was completely swapped out when I tested using the desktop vs the laptop as the AudioBox USB is powered by the USB interface.

Regards,
Kip....
 
Kip Carter said:
Ah well the power source was completely swapped out when I tested using the desktop vs the laptop as the AudioBox USB is powered by the USB interface.

Regards,
Kip....
Click to expand...
Dumb question, do you have the main output on the Audiobox cranked up? I keep mine about 1/2 to 3/4 the way. My apologies if this is overly obvious, but I had an issue with mine due to setting the volume and gains too high on the box.
 
No not a dumb question. I have i pegged! Reason being is that amplitude is suffering terribly already on the recording so I do have it maxed. if that is not allowable why on earth have a pot that goes beyond a usable range? But anyhow I digress, yes it is capped out.

Regards,
Kip...
 
Kip Carter said:
No not a dumb question. I have i pegged! Reason being is that amplitude is suffering terribly already on the recording so I do have it maxed. if that is not allowable why on earth have a pot that goes beyond a usable range? But anyhow I digress, yes it is capped out.

Regards,
Kip...
Click to expand...

So, the loudness issue is a different matter. If your monitors are not powered, you will need to get an amp as this box is too small to have any real power, it is more of a pre-amp. Now, if you have an issue with the loudness of the music, that is why you are here. You will work to fix that as a part of your mixing undertaking.
 
DM60 said:
So, the loudness issue is a different matter. If your monitors are not powered, you will need to get an amp as this box is too small to have any real power, it is more of a pre-amp. Now, if you have an issue with the loudness of the music, that is why you are here. You will work to fix that as a part of your mixing undertaking.
Click to expand...

Oooer! I might have given you a bum steer here Kip!
Bet you have Win 7? If so look in the Sounds and Audio menus and find the Recording Device (prob call it a USB mic!) and I bet you will find it at 100%,. Crank it back to 5%, maybe less.

This will not cure the hummy buzz but it will put it well down into the noise floor...I think!

Dave.
 
DM60 said:
If your monitors are not powered, you will need to get an amp as this box is too small to have any real power, it is more of a pre-amp.
Click to expand...

DM Dave, did you see the drawing I posted earlier about my layout. The Harmony-G XT functions as a preamp for the vocal and guitar input. Out the back of the AudioBox USB obviously is my usb cable to my computer and DAW then the I run the headset or monitor out to the AUX on my 60w PA.

I'm not savvy but my novice mind says this is plenty of preamp to at least lay down tracks that will approach the limiters. But what I'm seeing is considerably low perhaps 20% of potential.

I wouldn't be surprised to find out I've done something wrong.

Regards,
Kip...
 
ecc83 said:
Bet you have Win 7?
Click to expand...
Yes Windows 7 for the laptop but desktop (doing the same) is windows 8.

ecc83 said:
If so look in the Sounds and Audio menus and find the Recording Device (prob call it a USB mic!)
Click to expand...
Negative - I have the Presonus driver loaded so it is the AudioBox

ecc83 said:
and I bet you will find it at 100%,. Crank it back to 5%, maybe less.
Click to expand...
The AudioBox drive IS set to 100% by default. Interesting that I found another tab on this driver that is called 'Enhancements' and on that tab there is a box that is called 'Low Frequency Protection'. This was not checked. Going to check that and see what happens.

ecc83 said:
This will not cure the hummy buzz but it will put it well down into the noise floor...I think!
Click to expand...
Will play with it but at 5% it likely will have no sound! lol ... well we are exploring more avenues anyhow. thx!

Regards,
Kip...
 
Update...
master volume = 0%
Input 1 = 0%
Input 2 = 0%
hum still present

I also turned down both output and input levels on windows driver for the AudioBox USB with same results.

I have managed to find a way to mitigate the hum (not eliminate it by adjusting the PA's Aux and master volumes. It is still apparently when I'm not playing or singing but the guitar and vocals cover it fairly easy. I think i'm headed for the hum destroyer (HD400) from the looks of it. Had hoped to avoid spending more money but beginning to look doubtful that is possible.

Regards,
Kip...
 
Master volume on the box itself, 50%/75%. Input gains on the box less 75%.
 
Kip Carter said:
On the headphone bit. As i fully expected same hum there as well. Now what I did notice when I went to reach for the plug to undo it is that the amplitude increased as my hand got close to the jack so it would seem like some form of RF energy generating the hum.
Click to expand...

Was the PA system completely removed from the setup at this point, rather than just turned off?

Unplug absolutely everything - All mains plugs, jack cables: Everything.
Start with laptop and headphones (built in audio). Check the mic input in your DAW.
If that checks out introduce the interface and plug the headphones in there.
Check the interface inputs in your DAW. Try with and without the laptop mains supply.

If there's buzz at this point either take it all to a different room of the house and try again, or methodically go around the room turning off everything :- Fans, TVs, lights, A/C.
Replace any cables that you can, incuding the USB cable. Even try a different USB port.


IDK, all worth a try I guess.

Has this setup ever worked without buzz?
 
yes with just headset no input and Audiobox hum present. I guess what the follow up question should be is what about the USB interface (AudioBox USB) is there a better interface I could use? If i'm gonna end up spending 30 dollars to eliminate the buzz, how much more would I have to spend to have better setup? I didn't win the recording studio setup from GC so I'm on my own dime. <sigh>

Regards,
Kip...
 
Kip Carter said:
yes with just headset no input and Audiobox hum present. I guess what the follow up question should be is what about the USB interface (AudioBox USB) is there a better interface I could use?
Click to expand...

If you have buzz in the headphones with just the interface connected, the laptop psu unplugged and no other mains devices connected to the laptop, then either your laptop is bust or your interface is.

I'd try the interface on a friend's computer to figure out which. :)
 
Then it would sound like my interface because I used it on my desktop with the very same results. Guess I'm shopping for a new interface even though this one is like brand new. Shessh..

Regards,
Kip...
 
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