Today I decided to track down a problem that I have in my guitar sound and annoied me for a long time. And I found a very odd situation.

The problem: a high pitched buzzlike distortion.

Have noticed earlier that it may come from the guitar, but first I though the pedals do it in my chain. What revealed is that pedals only enhance it, but they are not the source of the problem.

I did some tests today. I compared two sources:

1. I connected my guitar to my Zoom G1 multieffect. I plugged my JBL headphone into the multieffect, and started listening for the buzz. It is most articulated when playing note pairs around the frets: 20-24 (I opened posts earlier about intermodulation in that range, but it is not the same sound effect).
And I did not hear it.

2. I connected my guitar directly to my Alesis iO4 interface. And the buzz was audible. Recording the guitar directly, it may not be audible at normal mixing and mastering levels. But when the signal goes through compressors or other effects before the interface, it may be audible at that level, too.

I experimented further and I got very odd results:

- Interface switched on, its USB cable disconnected from the computer: buzz is audible from the JBL headphone plugged into Interface OUT

- Interface switched on, its USB connected to the computer: buzz is audible from the JBL headphone plugged into Interface OUT

- Interface switched on, USB disconnected from the computer: buzz is not audible from my Oneodio 64 monitor headpones plugged into Interface OUT

- Interface switched on, USB connected to the computer: buzz is not audible from my Oneodio 64 monitor headpones plugged into Interface OUT

At this point you may say: okay, the JBL headphones are faulty. But remember: plugging the JBL into the multieffect and listening from there directly the buzz was inaudible. And you may say: ok, the multieffect changes the sound. So I also tested:

- Guitar plugged into multieffect, multieffect connected to the interface, listening with JBL from the interface: the buzz is there.

So from all this, it may seem like the problem might be the interface.

And this is where things got interesting.

- Plugged my guitar directly to the interface. Recorded the note pairs that makes the buzz in the JBL. Saved them as .wav. Opened the wav in Spectralayers. Set the interface to be the output (through ASIO) : bamm, the buzz is there in the JBL headphones. Changed output in Spectralayers to Laptop out (Windows driver): NO BUZZ in the JBL!!!

Now you can say if you did not read what I wrote properly: the Asio driver is crap. But remember: the buzz was there as well when the interface was not connected to the computer, too.

Experimenting further the things just became more interesting:

- Connected the interface to the computer. JBL was connected to interface out. Opened the recorded wav in Windows Media Player: TADAAM NO BUZZ from the INTERFACE!!!

Anyone understands what's happening here?

By the way: I tried this on Mac, connected the interface to the computer, opened Logic, set the monitoring to software monitoring (direct monitoring on interface was turned down) and the buzz was there.

Here is the sample I recorded. Once more: this is from the guitar connected directly to the interface. The interesting is: the wave seems to be clipping on the top half at certain moments, but then at other moments for larger amplitudes it is still not clipping. How is that possible??? You may say that is the source of problems, but why can't you hear the buzz when playing the recording with Windows Media Player then, or when the JBL headphones are plugged directly into the Multieffect? I checked and I did not have EQ on in Windows Media Player.

Crank up the volume when listening or you may not hear it:
https://drive.google.com/file/d/1hQQyvS ... sp=sharing