7500 hz

Necrobump, I know.

But I have the same problem here, just tried a few things out and I'm stumped, it's really annoying me now, seems to get worse as I get near my comps PSU, but it's not a cheap psu, maybe a cheap cable I dunno.

A DI box plugged in with no guitar plugged in and I get noise.

Any ideas?
 
Just an educated guess but, if it sounds more like a distorted sine wave (square wave), it would be the switching frequency of the power supply, in which its frequency is high enough to make it through the shielding of the cable since the cable rejects interference through capacitance, if the interference is high enough frequency to get past the capacitance of the cable (which is determined by cable length) it could get into the desired signal. It (the PSU) could also inflict a noise into the actual ADC through the motherboard itself if you are using a PCI type interface if you have a poorly designed motherboard (not enough filtering for the switching frequency). Without proper equipment and training, it could become really hard to find the culprit however.
 
lol thread from the dead. dude... if you havent solved this yet, plug in the power supply to your firebox. you can suffer an electrical ground loop even if all of your gear is plugged into the same outlet.... i can get a couple db drop (volume cranked) if i simply plug in the powersupply. the power - through firewire - from the computer isnt clean enough to provide more floornoise and can produce noises/hums in any range depending on a lot of things like transistors and cable wires... try different power supply cables on your dekstop machine too. the only other thing i can think of is if someone is broadcasting around you, maybe an AM station or someone with old broadcasting gear something like that.

.... if nothing else man.... try to come in contact with an electrical engineer. my brother in law is one so ill talk to him about it see what he says.

and just for futures sake of no noise for anyone, if a piece of equipment can run without a powersupply, dont take chances, just plug it in. if you dont need it, dont put more hours on it by leaving it on.
 
Did Joey ever fix this? Or is he just outsourcing all the DI recording?
Would be nice to know.

But is Joey even checking this forum since he got his own ?

After all that flaming directed at his followers - flaming that came from some of our beloved drama queens on a rag...
 
I was getting a noise from my RME babyface, took me forever to figure it out. But one day all i did was slightly loosen one of the screws that hold the breakout cable to the interface and it went completly away, tightened it back up, noise came back. Weird!
 
I think my issue is due to the power to my computer, as it happened when I had my Delta1010LT as well as the Saffire I'm using now, so it's not a power to the interface problem I don't think.
 
i had a similar issue a couple of years ago... with 8khz.

it was everywhere. turned out that somebody had a metal-work-shop around the corner with a huge cnc cutter which interfered into the power network as the power consumed by the cnc machine (60 amperes) was to much for the the power connections to his shop (only 63 amperes).

he upgrade to a 126 amperes connection and build in some power low pass filters* (yes there is a low pass filter for power). he got some "gleichrichter" for his cnc cutter to, but it just lowered the noise, you could still here it in amps with distortion... we tried power low pass filters our self for our power connection, but we've had no luck, we moved the studio...


*power low pass filter cuts out everything over 60hz from the power line