New Ultra - Radio Noise

favance

favance

Power User
Hi. First of all thanks for a great product. I can't believe the sounds available in this box compared to my "other" high-end modeling gear. I've only had the Ultra for less than a week and still learning. I am playing w/a Strat Deluxe w/Cobalt Noiseless pickups and a Brian Moore Custom C90P. I am using QSC K12 for the Amp/Speaker. I have the unit plugged into a Monster Power Conditioner and am using high-end cables (Death Valley Cables). My house is was built less than 15 years ago.

The problem is on several patches I'm picking up Radio Stations on several patches. I've never had this issue on any other gear in my studio...w/the same guitars and other amps. Any ideas on what could be the issue? Is this a defective unit?

thanks!
Alan
 
Sounds like Cliff updated the "tuner" module. Can you pull in the "X"? :lol:


Actually, this is probably a case of RF injection (not AC line noise), since you can hear radio-station traffic in the noise floor. Something in your rig may need additional shielding, or to have faulty shielding corrected.

Before you can resolve an interference problem you must isolate the actual interference source. Interference originates from many sources - the equipment itself, your residence, or the neighborhood.

The two most common causes of interference are transmitters and electrical equipment. Communication systems that transmit signals (transmitters) are capable of generating interference; these include amateur radios, CBs, and radio and television stations. Electrical interference may be caused by power lines or electrical equipment in your home.

Transmitter interference is normally caused by the actual design of the (interfered-with) equipment itself. Many manufacturers do not protect internal wiring with adequate shielding or sufficient filtering, so the interfered-with equipment is susceptible to receiving unwanted signals – interference.

The source may be as simple as a frayed wire that connects a signal input to an amplifier. A faulty wire can act as an antenna that will carry interfering signals.

To determine whether the interference is coming from the interfered-with equipment itself, unplug one component at a time on the interfered-with equipment or on other equipment to see if you can isolate the source. Also, disconnect other electrical equipment (answering machines, telephones, fax machines, etc.) one by one.
 
I'm not sure I understand everything you're saying. However, when I unplug the guitar, dead silence. Both guitars are quite plugged into other gear in the same room (I own a Vetta II). I've used other gear w/the QSC. The only thing that seems to subject to the Radio Interference in the room is the Axe-Fx...and only when there's an instrument plugged in and only on certain high-gain patches (not all patches produce this noise). Does this make any sense?
 
Bear in mind that the Axe-Fx has a built-in Noise Gate -- this may be the reason why it's "dead quiet" when no cables are inserted into its inputs.

It makes sense that you'd hear the injected RF noise on higher-gain presets, exactly because the extra gain in those presets is amplifying the noise (and your guitar signal) appearing at the input.

Which guitars does it seem to happen with?
 
Ii think I may know why .. The guitar cord happens to be a certain partial wavelength of the frequency from the transmitter. So when you plug into the Ultra on high gain settings the guitar cord acts like an antenna of sorts amplified by the ultra's preamps, and wah la, a ham radio... Try a different length premo guitar cord and see if it(radio noise) is gone....

Thats my guess anyway :cool:
 
RF can be very, very frustrating....but most likely it is not the axefx, but you are now noticing it because of the gain staging in the axefx.
Guitar shielding and guitar cables are the most common factors introducing RF.
Try moving you rig to another room, face your guitar in different directions around the room and listen for dropouts in the RF signal.
How far are you away from the axefx while tweaking or playing...how far away are you from other electrical equipment in the room?

One thing to be sure is that the axefx is properly grounded if in a rack...ground that Monster Power conditioner to the rack rails (i use copper speaker wire from the ground post to a screw in the rack rail). Use Hum-free's rack isolators or some method to isolate the pieces of gear from each other.
I had real issues when i first set up my rack, and it wasn't one little thing that solved the issue. it was a combination of things which cleaned up the signal...but now, it is dead quiet.
Good luck, dont get too frustrated, you'll find it. Dont spend your time thinking it;s the axefx, most likely it is not the source.....focus on achieving proper grounding first and isolate each piece so you can rule out items.
 
Mike Snider said:
RF can be very, very frustrating....but most likely it is not the axefx, but you are now noticing it because of the gain staging in the axefx.
Guitar shielding and guitar cables are the most common factors introducing RF.
Try moving you rig to another room, face your guitar in different directions around the room and listen for dropouts in the RF signal.
How far are you away from the axefx while tweaking or playing...how far away are you from other electrical equipment in the room?

One thing to be sure is that the axefx is properly grounded if in a rack...ground that Monster Power conditioner to the rack rails (i use copper speaker wire from the ground post to a screw in the rack rail). Use Hum-free's rack isolators or some method to isolate the pieces of gear from each other.
I had real issues when i first set up my rack, and it wasn't one little thing that solved the issue. it was a combination of things which cleaned up the signal...but now, it is dead quiet.
Good luck, dont get too frustrated, you'll find it. Dont spend your time thinking it;s the axefx, most likely it is not the source.....focus on achieving proper grounding first and isolate each piece so you can rule out items.
Click to expand...

Thanks Mike. I don't have the Axe in a Rack yet. I've tried several different cables and it happens on more than one Guitar (Strat and Brian Moore guitars). So, I'll try your other suggestions. How did you ground/isolate the axefx in the rack? Thanks again.
 
i'll assume you have the monstor 2500 conditioner.
there is a grounding post on the back of the unit- it screws in and out like the terminal post on a home stereo spreaker. I took a piece of speaker cable- connected it to the terminal post on the conditioner,fed it to the rack rail and using a screw in one of the open mounting positions on the rail,- secured the speaker wire to the rail.
In my case, this went a long way to cleaning up my interference- the conditioner was actually intruducing noise.

http://accessories.musiciansfriend.com/ ... sku=544710
these iso tabs will help to keep the pieces isolated- basically you are trying to avoid metal to metal contact.

Again, there may be more than one source- there was in my case. The key to finding it, even with just a few components, is to test mythodically. Just swapping things out wont confirm anything. Strip your gear down to minimum, adding pieces only after confirming the absence of RF. I know you would rather just play guitar- but you will chase your tail if you just swap things out. I did.
 
Mike Snider said:
i'll assume you have the monstor 2500 conditioner.
there is a grounding post on the back of the unit- it screws in and out like the terminal post on a home stereo spreaker. I took a piece of speaker cable- connected it to the terminal post on the conditioner,fed it to the rack rail and using a screw in one of the open mounting positions on the rail,- secured the speaker wire to the rail.
In my case, this went a long way to cleaning up my interference- the conditioner was actually intruducing noise.

http://accessories.musiciansfriend.com/ ... sku=544710
these iso tabs will help to keep the pieces isolated- basically you are trying to avoid metal to metal contact.

Again, there may be more than one source- there was in my case. The key to finding it, even with just a few components, is to test mythodically. Just swapping things out wont confirm anything. Strip your gear down to minimum, adding pieces only after confirming the absence of RF. I know you would rather just play guitar- but you will chase your tail if you just swap things out. I did.
Click to expand...

Mike, I will probably put a Furman Power Conditioner (can you recommend one over the other...what are you using?) in the 4-up Rack Box, along w/my Sure P4T Wireless In-Ear transmitter and the Axefx. So, I will start by putting a good, grounded, power conditioner and iso-tabs in the rack. If the problem still persists, what would I check next? How do I break it down?
 
lets try to figure out the issue before it goes in the rack (i missed that you mentioned that it was not in a rack on the last response).
First off- are there any obvious factors contributing to the RF? Antenna nearby? radio stations nearby? Is your guitar near a router, are you tweaking 1-2' away from your axefx?
remove the power conditioner, go- guitar to axefx to QSC...make sure the axefx is plugged into a grounded source, cables are not crossed or touching anything else. play- note the occurances of RF. When you get an RF signal- identify the spot, then change you playing position in the room- see if the signal goes away. I used to get it when i faced a certain direction in my house, and other times in our practice room when i leaned against walls framed with metal studs (that one still puzzles me).
Then return to the spot with the RF signal and change cables (including brand- use any other instrument cable not made by the same manufacturer) without changing anything else.
If the result is the same- try a different guitar and go thru the exact same process. Does it happen in the exact same place, is the RF louder, softer, etc.
Set up in a different room, go thru the same process.
The idea is to isolate each component to find which piece receives the RF signal.

Ultimately, i reshielded my guitar- you may not have to go that far.

Others may have a better process, these are the kind of steps i went thru to find the problem.
 
I'm having the exact same problem with multiple guitars. It started recently and I'm really hoping it has to do with some new cables I swapped into my rig. I'm really getting tired of hearing the hispanic gospel station on my high gain patches. :lol:
 
favance said:
I'm not sure I understand everything you're saying. However, when I unplug the guitar, dead silence. Both guitars are quite plugged into other gear in the same room (I own a Vetta II). I've used other gear w/the QSC. The only thing that seems to subject to the Radio Interference in the room is the Axe-Fx...and only when there's an instrument plugged in and only on certain high-gain patches (not all patches produce this noise). Does this make any sense?
Click to expand...
Yes. The guitar/cable is always picking up RF, but the other equipment has sufficiently high RF immunity that it is not being detected (converted to audio frequency). Something in the Axe-Fx's input circuitry is detecting the RF. The resulting audio is at a low enough level that it is only audible on higher-gain presets.

Given that this problem hasn't, to my recollection, been reported on the forum before, I'd say it is likely - but not 100% certain - that something is amiss in the input circuitry of your unit, perhaps a cold-solder joint, which can function as a detector diode.
 
marshall2553 said:
I'm having the exact same problem with multiple guitars. It started recently and I'm really hoping it has to do with some new cables I swapped into my rig. I'm really getting tired of hearing the hispanic gospel station on my high gain patches. :lol:
Click to expand...

Ok...my RF is also picking up a spanish radio...for a minute I thought Estaban was trying to remote control my AxeFx :cool:
 
Jay Mitchell said:
favance said:
I'm not sure I understand everything you're saying. However, when I unplug the guitar, dead silence. Both guitars are quite plugged into other gear in the same room (I own a Vetta II). I've used other gear w/the QSC. The only thing that seems to subject to the Radio Interference in the room is the Axe-Fx...and only when there's an instrument plugged in and only on certain high-gain patches (not all patches produce this noise). Does this make any sense?
Click to expand...
Yes. The guitar/cable is always picking up RF, but the other equipment has sufficiently high RF immunity that it is not being detected (converted to audio frequency). Something in the Axe-Fx's input circuitry is detecting the RF. The resulting audio is at a low enough level that it is only audible on higher-gain presets.

Given that this problem hasn't, to my recollection, been reported on the forum before, I'd say it is likely - but not 100% certain - that something is amiss in the input circuitry of your unit, perhaps a cold-solder joint, which can function as a detector diode.
Click to expand...

I wont negate what Jay said- he knows far more than i do.
I will only offer that i did have the same experience....it's been about 2 years. I went as far as sending the unit back. New unit arrived and had the same problem. In my case it was guitar shielding that caused a majority of the RF- but i didnt figure it out untill i isolated the component.

Jay you may be right on the money. Is there any way for the OP to test this?
 
Jay Mitchell said:
favance said:
I'm not sure I understand everything you're saying. However, when I unplug the guitar, dead silence. Both guitars are quite plugged into other gear in the same room (I own a Vetta II). I've used other gear w/the QSC. The only thing that seems to subject to the Radio Interference in the room is the Axe-Fx...and only when there's an instrument plugged in and only on certain high-gain patches (not all patches produce this noise). Does this make any sense?
Click to expand...
Yes. The guitar/cable is always picking up RF, but the other equipment has sufficiently high RF immunity that it is not being detected (converted to audio frequency). Something in the Axe-Fx's input circuitry is detecting the RF. The resulting audio is at a low enough level that it is only audible on higher-gain presets.

Given that this problem hasn't, to my recollection, been reported on the forum before, I'd say it is likely - but not 100% certain - that something is amiss in the input circuitry of your unit, perhaps a cold-solder joint, which can function as a detector diode.
Click to expand...

Jay, Mike and others have reported they have the same issue...here's a thread that talks about a similar issue: http://www.fractalaudio.com/forum/viewtopic.php?f=11&t=11398&hilit=radio+noise

I really don't want to send the unit back...but it does appear there may be something to this. I will try to do some more work tonight to isolate the issue...per Mike, my unit is in a room were less than 2 feet (through the wall) I have my wireless router. I will try to isolate this...but, since no other gear I have used (for rehearsals/recording) has ever had this issue, it does seem that the Axefx may be more succeptable or that a few of us may have an issue on our specific units.
 
marshall2553 said:
I'm having the exact same problem with multiple guitars. It started recently and I'm really hoping it has to do with some new cables I swapped into my rig. I'm really getting tired of hearing the hispanic gospel station on my high gain patches. :lol:
Click to expand...

Happens to me, too...
 
Mike Snider said:
I will only offer that i did have the same experience....it's been about 2 years. I went as far as sending the unit back. New unit arrived and had the same problem. In my case it was guitar shielding that caused a majority of the RF- but i didnt figure it out untill i isolated the component.
Click to expand...
As I pointed out, the RF is present in all cases with the OP. It is the detection of the RF that is happening with the Axe-Fx and not with the other gear. Minimizing RF susceptibility is a huge design challenge, and ultimately it is the design of the signal processing gear that determines whether RF can be inadvertenly downconverted to AF (Audio Frequency) and amplified.

Jay you may be right on the money. Is there any way for the OP to test this?
Click to expand...
Well, he's already established that there are no radio stations playing when he connects the same guitar/cable into other gear. That does a pretty good job of narrowing down the problem to the Axe-Fx. Clearly it's happening at the input, because it's only audible with high-gain presets. Here's the point it is the job of audio gear to limit its bandwidth to the intended one (i.e., audio frequencies). It is possible that shielding the guitar will be helpful, but the Axe-Fx really shouldn't be detecting RF.
 
Jay Mitchell said:
[quote="Mike Snider":1sxymu5s]I will only offer that i did have the same experience....it's been about 2 years. I went as far as sending the unit back. New unit arrived and had the same problem. In my case it was guitar shielding that caused a majority of the RF- but i didnt figure it out untill i isolated the component.
Click to expand...
As I pointed out, the RF is present in all cases with the OP. It is the detection of the RF that is happening with the Axe-Fx and not with the other gear. Minimizing RF susceptibility is a huge design challenge, and ultimately it is the design of the signal processing gear that determines whether RF can be inadvertenly downconverted to AF (Audio Frequency) and amplified.

Jay you may be right on the money. Is there any way for the OP to test this?
Click to expand...
Well, he's already established that there are no radio stations playing when he connects the same guitar/cable into other gear. That does a pretty good job of narrowing down the problem to the Axe-Fx. Clearly it's happening at the input, because it's only audible with high-gain presets. Here's the point it is the job of audio gear to limit its bandwidth to the intended one (i.e., audio frequencies). It is possible that shielding the guitar will be helpful, but the Axe-Fx really shouldn't be detecting RF.[/quote:1sxymu5s]

favance - perhaps it is wise to contact fractal support to discuss the issue.

I dont want to mislead you in any way - i chased my tail for a long time addressing this issue. For me, reshielding my guitar was the answer. I dont know enough about electronics to know wether the shielding or the mod i did at the same time addressed the issue- but i did eventually fix the problem (in my case it very well may have been by chance).
to correct an eariler statement i made- grounding the conditioner was not a factor in solving the RF, i am now recalling the multiple issues i had and addressed many at the same time. Isolation and grounding are important- just not direct contributors the the issue of RF I was experiencing.
One of the reasons i chased my tail for so long is that i had multiple issues -RF, grounding, and others- and was addressing all at the same time. it wasnt until i isolated everything and worked the issues one at a time that i was able to clean things up. My memory is a casualty of hard living in my younger days.
 
Thanks Jay/Mike and all others who contributed...I did notice last night that the "Input 1" Level control was scratchy when I rotated it. So, my analysis (along w/Fractal Support) was that there may be some component issues w/the unit I had. I returned the unit for Fractal's inspection...

The bottom line is, this has been a very positive experience for me. I had an issue and within a few hours basically, I have several great recommendations and a very rapid response from Fractal. There will always be some product issues (other manufacturer's have many more). What they DO NOT have is what I believe we have with the Fractal...i.e. a very responsive, supportive, and knowledgeable user community and a company dedicated to providing the best product and support possible, something that is very rare in this day and time.

Again, thanks!
 
Mike Snider said:
For me, reshielding my guitar was the answer.
Click to expand...
As I pointed out above, this may address the immediate problem - that of RF being applied to the input of the Axe-Fx - but it does not address the underlying issue: the Axe-Fx detecting and amplifying RF signals. It is true that an unshielded guitar is more likely to pick up RF, but it is equally true that well-designed processing gear will reliably reject the RF, and you will never hear it.

Here are some links with good information: http://svconline.com/mag/avinstall_unde ... olling_rf/

http://www.rane.com/note166.html

http://ieeexplore.ieee.org/Xplore/login ... ision=-203
 
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