Hum from Hell

dogman211296

dogman211296

Member
Hey guys. Still fairly new here and to the fractal gear but I have a major hum crisis running my fx8 through my cameron atomica and my modded jcm800. I was hoping someone knows whats going on or what Im doing wrong. Any help would be greatly appreciated.

I've tried running it with my full board and also running just the fx8 in 4cm. I am using humbuster cables for the send & return ends on the fx8 and an ebtech hum x at my power source. I've also tried running it through just the front end and not using the loop at all. There is no clipping and if I go in to the global settings and lower either the pre or post gain it does go away to the point that my decimator will kill the remaining hum completely but its gated so hard the tone is unusable.

This rig sounds great but the hum is so bad I could never gig with it mic'd up. I've tried everything and read all the threads concerning ground loops but man, this is brutal and Im not sure if its just doing something stupid or if I've got something wrong. Im ready to throw it out the window. lol

Thanks
 
I usually start by disconnecting each cable (and then plug back in) and see which ones change the level of hum.
If you disconnect the input cable to the AFX, does the hum stop? Take note.. Then on to the next cable, etc..
The devices in your rig should be powered from a single strip.
Try drawing a block diagram of the units in your rig, including signal chain, and AC power chain, and post it here.
 
Thanks for the reply.

For testing purposes I have simplified the rig to minimize the possible problems and is as follows:

Whole rig is run off of the same AC supply strip plugged in with a hum x
Cameron Atomica head into a 4x12 cab running at 16ohms
FX8 in 4cm so the chain is

guitar> fx8 in pre
amp send to ebtech hum eliminator 1 in then out to fx8 post in using humbuster cable
amp return to ebtech hum eliminator 2 in then out to fx8 return post out using humbuster cable
fx8 pre out to amp input

I have pulled each cable one at a time to see if there was a difference in hum and the findings are

pull fx8 send or return noise gone
pull pre out to amp and noise drops in intensity
pull send out of back of amp no difference
pull return out of back of amp noise gone

Im pretty sure its hooked up right hopefully...lol
 
what side of the humbuster cable is the TRS side plugged into? who made the humbuster cables?

have you tried without the ebtechs?
 
chris said:
what side of the humbuster cable is the TRS side plugged into? who made the humbuster cables?

have you tried without the ebtechs?
Click to expand...
Right now the fx8 side. But I've run it both ways without the ebtech and using and switching sides of the humbuster cables. Which are brand new direct from fractal.
 
dogman211296 said:
Right now the fx8 side. But I've run it both ways without the ebtech and using and switching sides of the humbuster cables. Which are brand new direct from fractal.
Click to expand...
the TRS side always goes on the FX8 side. smart to try the other way as a test though.

what happens if you unplug the guitar and its cable, but leave all other cables in - still has the noise?
 
chris said:
the TRS side always goes on the FX8 side. smart to try the other way as a test though.

what happens if you unplug the guitar and its cable, but leave all other cables in - still has the noise?
Click to expand...
Yes.
The only time is doesn't hum is when running the guitar straight into the amp.
 
To beak a ground loop, the ebtech Hum-X is only plugged into the power cord of the amp you are using. This breaks the ground loop & changes polarity or something like that.

If you plug it into the end of the power strip & everything goes thru it, you've changed nothing.

You may already know this & be doing thIs, but I can't tell from how it's worded here.

Do you have any pictures of your set-up that you can share? This may help in trouble shooting this hum issue.

Are you running 2-amps at the same time?

Or was it just your example the both amps have the issue when used seperatly in 4cm?

X
 
Last edited:
I am using it on the amp only but I did try it both ways. Its quite perplexing. When I run my analog board using the same cables, no hum.
 

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My suggestion (it'll take some time) would be to disconnect everything including all signal cables (not speaker cables of course), and the Hum X.

Now you start from SCRATCH. You already said Guitar into one amp = no hum so...with step you are figuring out where the hum starts. And don't use any humbuster cables at all yet. Also, remember to set your FX8 I/O settings appropriately for each step. Okay, so...

1. Plug one amp into the power strip (I'd actually prefer straight into the wall here, but I'll leave that up to you).
2. Setup the FX8 with one amp in PRE only (as in manual).
3. Change to FX8 post only, same amp
4. FX8 4CM same amp

Using one amp, you really shouldn't have ground loop issues. 4CM can sometimes cause that depending on your loop. So my guess is you'll have no hum yet.

5. Now plug the other amp into the power strip (or the same wall socket if you didn't start with the power strip) and turn it on. Don't even connect anything to the input or FX loop. Just check for hum with both amps powered on.
4. Next, FX8 PRE only with both amps
5. FX8 post only with both amps
6. FX8 4CM with both amps

Remember, don't use humbuster cables or the hum X yet.

So do those in order and stop and report back as soon as you get the hum.
 
ok plugging amp straight into the wall, hum started right out of the gate at step 1 pre only with just the guitar and pre out.
I went through the rest of the steps anyway just to see if there was any change, but the hum is consistent.
 
So direct into the amp's preamp, there is no hum - but direct into the AFX, and AFX direct into 'effects return' of amp there is hum.
Have you matched gain in each instance? The more gain the more hum.
So to compare hum, the AFX and the amp's preamp should be set to the same gain, and output the same level to the power section of the amp.
 
dogman211296 said:
ok plugging amp straight into the wall, hum started right out of the gate at step 1 pre only with just the guitar and pre out.
I went through the rest of the steps anyway just to see if there was any change, but the hum is consistent.
Click to expand...

And here's no hum when plugged into the wall and guitar straight into the amp, right? Does that still happen with the pre-only setup with your other amp? If this is the case, it does suggest there may be an issue with your FX8. It's possible that wall outlet or power in the house is a problem. Can you try other outlets in different rooms? I'd even suggest trying someone else's house if you can. If that pre only setup is causing noise even with good power from mains, it may be time to contact Fractal support.
 
Dogman, did you try any different patch cables in that pre only setup? Just to make sure you don't have a wonky cable? I didn't think of that because you mentioned having no hum with the analog board, but that's also worth checking since it's so easy to swap one out. I'm really hoping you get it sorted because the FX8 is badass.
 
I did try using all new cables and tested them. I was really starting to dig the fx8. This is a major bummer. Im gonna keep trying to figure it out and hopefully its just something stupid. smh

Lance Holland said:
Just wondering. I have an 80's JCM 800 and the effects loop is completely unusable.
Click to expand...
The effects loop in the 2205 is rough, but Ive been able to use it with success. Now the Atomica is just a friggin beast of an amp and the tone is to die for. It sucks when I can have that for tone with the fx8.
 
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