Axe-FX II "Microphoning"

Morbid

Morbid

Inspired
I noticed recently when I set something on my rack case, that the thump the object made when it hit the rack, came through my cabinet, delay effect and all.

So I started testing. Tap on the power amp...nothing. Tap on the axe-fx, and it comes through the cab with whatever effects I have going. Unplugged the guitar, tapped the Axe-FX, still coming. Hit the tuner, and no microphoning to be heard.
Anyone have any ideas? Something I'm missing perhaps?

I took a look through the manual and a quick search on the forums and didn't find anything.
I have the Axe-FX running to a Matrix GT1000FX with a standard quarter inch cable.
 
Cliff: "Anything with lots of gain will be microphonic to some degree. If you pull the input cable you exacerbate the microphonics by orders of magnitude since there is no load. Microphonics are normal. Try cranking up a tube amp and tapping on the chassis"
 
Bummer. This is microphonic enough that it's feedbacking from vibration in the room from other instruments, even with my guitar turned down or unplugged.
Pulling the input cable doesn't seem to change anything.
 
MOrbid, if you can share a preset and recording so we can see how much gain you're using. It could be to much gain, it could be something else, would be nice to hear and see.
 
Weird, I usually use way more gain than I really need for the type of music I play, and I've never run into this issue. I even keep my gate pretty light to the touch too.


Sent from my iPhone using Tapatalk
 
I've got a pretty hefty amount of gain on the patch, not gonna lie. Maybe even a little overkill.
I of course notice it must when I'm using my lead patch, which has a distortion pedal in front.

I'll get a screenshot posted later. The axe is in another room and I have to reinstall all of the software.
 
I believe Cliff made an admission about this for the Mark I, and possibly the Mark II units.

It was one of the items addressed in the designs for the XL series. Something to do with the way the circuit boards were made/designed, as I vaguely recall.

I have a Mark I and fortunately, have never experienced this. However, I play with in-ears and direct into a system, and my rack has never been within 50 feet of the drums on stage. So, I've never had to deal with vibrations aggravating the unit.
 
From Cliff last fall...
FractalAudio said:
Anything with enough gain will be microphonic. It's primarily due to the circuit board and any ceramic capacitors. The ceramic caps are piezoelectric so they will convert any acoustical energy into electrical energy. The circuit boards flex (microscopically) which causes strain in the traces which is converted to electrical signals.

The Axe-Fx II strives to minimize this. The Mark II is comparable to most other modeler products. The XL has nearly completely eliminated this due to the use of PPS film caps in critical locations and a stiffer board mounting design.
Click to expand...
 
I play guitar with two hands so I don't have anything left (at least mentionable on a family forum) to tap on the Axe unit with while playing a high gain patch.....
 
Morbid said:
So what you're saying...is I Should go ahead and open up my Axe-FX, and replace the ceramic caps with PPS film caps.


I'm kidding.
Mostly.
Kind of.
Mostly...
Click to expand...
:lol

Actually, what I'm roundly hinting at is that, if you're getting so much microphonics that other instruments are causing you feedback, your gain may be set toward the impractical side of insane. Even the most outrageous death-and-destruction music starts to suffer when the gain is too high. If you can afford to back it down even a little, you'll reduce the problem.
 
A video of it and a preset would help. This doesn't sound right to me, you may have a fault or not
 
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electronpirate said:
Are you tapping your case Live so this is a problem?
Click to expand...

I like to practice my Samba in between songs.
Everyone likes a good Samba.

GotMetalBoy said:
Check out my Thread I started about this and there's links to other threads regarding it:
http://forum.fractalaudio.com/axe-f...-feedback-issue-when-no-guitar-connected.html

Here's a post I made too:
Click to expand...

Looks like there was never really a 'solution' found, eh?

At any rate, NMG asked, so I'm here to deliver.
2 Screenshots through Axe-Edit of my beloved patch, and a quick video to demonstrate. Sorry for the lack of volume, took the video with my phone.

Amp Block
patchamp.jpg


Drive Block:
patchdrive.jpg


Listen to me ramble like a blithering fool:
https://www.youtube.com/watch?v=MQVu3pwedvk
 
Your rhythm gain is already pretty nuts, even without the drive block: Input Gain approaching 9, Master up over 5...if you back down from there, you'll get more clarity, rawness and attitude out of your preset, and you'll get less microphonics.

The noise you're hearing is interference getting in through your pickups, exacerbated by the high gain (note that it goes away when you zero your guitar's volume pot; I bet it also changes a lot when turn to face different directions :) ) See what it sounds like when your dimmable lights are turned completely off (not just dimmed down, but "click" off).
 
Rex said:
Your rhythm gain is already pretty nuts, even without the drive block: Input Gain approaching 9, Master up over 5...if you back down from there, you'll get more clarity, rawness and attitude out of your preset, and you'll get less microphonics.

The noise you're hearing is interference getting in through your pickups, exacerbated by the high gain (note that it goes away when you zero your guitar's volume pot; I bet it also changes a lot when turn to face different directions :) ) See what it sounds like when your dimmable lights are turned completely off (not just dimmed down, but "click" off).
Click to expand...

I'll have to mess with the gain settings tomorrow, because it's a little late in the evening to be blasting the neighbors now, lol.
How far down would you suggest backing down?

As far as the dimmable lights, I tried that once and it didn't really change. BUT, while messing with the switch, it seems to create more interference. The closer I get to the switch too, the more gnarly it sounds, haha.
 
Morbid said:
How far down would you suggest backing down?
Click to expand...
That's up to your ears. You need enough gain to get the sound and feel you're looking for. Any reduction in gain will help your microphonic and interference problems. Maybe start by backing down the Input Gain, but experiment with both. I think you'll find a lower-gain setting that you like even more than you like your current tone.


Morbid said:
As far as the dimmable lights, I tried that once and it didn't really change. BUT, while messing with the switch, it seems to create more interference. The closer I get to the switch too, the more gnarly it sounds, haha.
Click to expand...

It might be one of those dimmers that's just noisy all the time. If you want to get funky, use an extension cord to run your rig from another circuit elsewhere in your hose, and then kill the circuit breaker that feeds your dimmable lights. See if you still get the interference.
 
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