Home |
Search |
Today's Posts |
#1
|
|||
|
|||
Can you explain this 50Hz hum??
This is so annoying. The only thing I have on are the computer and mixer
(and hence the power transformer I use here in Germany for my US gear). The mixer's first two channel inserts are connected to delta1010 ins1/2. There are two mics coming into those channels, but even with the mic cables unplugged and trim all the way down, the delta monitor shows the following: www.guitar-dreams.com/misc/delta1010problem1.jpg If I unplug the inserts it goes away. The recorded audio is http://www.guitar-dreams.com/misc/de...0waveform1.mp3 The spectrum analysis shows http://www.guitar-dreams.com/misc/de...0waveform1.jpg So, if I take the unplugged insert and touch it against any jack on the mixer, the input level on the delta then rises back to the level shown in the picture above (first one). I then touched it against one of the screws that is holding the delta on my rack and suddenly both delta ins 1/2 input levels dropped down. Not completely though. There is still a waveform there http://www.guitar-dreams.com/misc/de...0waveform2.mp3 with a similar specal analysis http://www.guitar-dreams.com/misc/de...0waveform2.jpg Any idea what is going on here? In both cases, the spectral peaks are at 50Hz which of course is no coincidence. I would be tempted to think it has something to do with the step down transformer I am using on my US gear. But in this apartment, if I turn on a stereo, I hear 50Hz coming through the speakers regardless of the transformer. I feel like I am just doomed in this apartment. I hear 50Hz everywhere. The fridge, etc,etc. |
#2
|
|||
|
|||
Can you explain this 50Hz hum??
On Mon, 27 Oct 2003 20:36:49 GMT, "me" wrote:
This is so annoying. The only thing I have on are the computer and mixer This sounds like a classic case of ground loop. First read the FAQ, then check back. BTW, it's called a loop because the ground path is one turn of a big transformer. If you break that path, no current can flow; hence, no hum. Good fortune, Chris Hornbeck new email address |
#3
|
|||
|
|||
Can you explain this 50Hz hum??
On Mon, 27 Oct 2003 20:36:49 GMT, "me" wrote:
This is so annoying. The only thing I have on are the computer and mixer This sounds like a classic case of ground loop. First read the FAQ, then check back. BTW, it's called a loop because the ground path is one turn of a big transformer. If you break that path, no current can flow; hence, no hum. Good fortune, Chris Hornbeck new email address |
#4
|
|||
|
|||
Can you explain this 50Hz hum??
I know about ground loops when it comes to driving 2 amps with one guitar,
and I know how that problem is solved. I feel this is different. I have never dealt with a problem that involves the computer. -brian "Chris Hornbeck" wrote in message ... On Mon, 27 Oct 2003 20:36:49 GMT, "me" wrote: This is so annoying. The only thing I have on are the computer and mixer This sounds like a classic case of ground loop. First read the FAQ, then check back. BTW, it's called a loop because the ground path is one turn of a big transformer. If you break that path, no current can flow; hence, no hum. Good fortune, Chris Hornbeck new email address |
#5
|
|||
|
|||
Can you explain this 50Hz hum??
I know about ground loops when it comes to driving 2 amps with one guitar,
and I know how that problem is solved. I feel this is different. I have never dealt with a problem that involves the computer. -brian "Chris Hornbeck" wrote in message ... On Mon, 27 Oct 2003 20:36:49 GMT, "me" wrote: This is so annoying. The only thing I have on are the computer and mixer This sounds like a classic case of ground loop. First read the FAQ, then check back. BTW, it's called a loop because the ground path is one turn of a big transformer. If you break that path, no current can flow; hence, no hum. Good fortune, Chris Hornbeck new email address |
#6
|
|||
|
|||
Can you explain this 50Hz hum??
"me" wrote in message s.com... I know about ground loops when it comes to driving 2 amps with one guitar, and I know how that problem is solved. I feel this is different. I have never dealt with a problem that involves the computer. -brian It is no different with a computer. However, you mentioned it is associated with an insert. I had the same problem and it was the cable. Try a new cable. -- Mike D. www.stopassaultnow.org Remove .spamnot to respond by email "Chris Hornbeck" wrote in message ... On Mon, 27 Oct 2003 20:36:49 GMT, "me" wrote: This is so annoying. The only thing I have on are the computer and mixer This sounds like a classic case of ground loop. First read the FAQ, then check back. BTW, it's called a loop because the ground path is one turn of a big transformer. If you break that path, no current can flow; hence, no hum. Good fortune, Chris Hornbeck new email address --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.532 / Virus Database: 326 - Release Date: 10/27/2003 |
#7
|
|||
|
|||
Can you explain this 50Hz hum??
"me" wrote in message s.com... I know about ground loops when it comes to driving 2 amps with one guitar, and I know how that problem is solved. I feel this is different. I have never dealt with a problem that involves the computer. -brian It is no different with a computer. However, you mentioned it is associated with an insert. I had the same problem and it was the cable. Try a new cable. -- Mike D. www.stopassaultnow.org Remove .spamnot to respond by email "Chris Hornbeck" wrote in message ... On Mon, 27 Oct 2003 20:36:49 GMT, "me" wrote: This is so annoying. The only thing I have on are the computer and mixer This sounds like a classic case of ground loop. First read the FAQ, then check back. BTW, it's called a loop because the ground path is one turn of a big transformer. If you break that path, no current can flow; hence, no hum. Good fortune, Chris Hornbeck new email address --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.532 / Virus Database: 326 - Release Date: 10/27/2003 |
#8
|
|||
|
|||
Can you explain this 50Hz hum??
Invert the phase.
"me" wrote in message s.com... This is so annoying. The only thing I have on are the computer and mixer (and hence the power transformer I use here in Germany for my US gear). The mixer's first two channel inserts are connected to delta1010 ins1/2. There are two mics coming into those channels, but even with the mic cables unplugged and trim all the way down, the delta monitor shows the following: www.guitar-dreams.com/misc/delta1010problem1.jpg If I unplug the inserts it goes away. The recorded audio is http://www.guitar-dreams.com/misc/de...0waveform1.mp3 The spectrum analysis shows http://www.guitar-dreams.com/misc/de...0waveform1.jpg So, if I take the unplugged insert and touch it against any jack on the mixer, the input level on the delta then rises back to the level shown in the picture above (first one). I then touched it against one of the screws that is holding the delta on my rack and suddenly both delta ins 1/2 input levels dropped down. Not completely though. There is still a waveform there http://www.guitar-dreams.com/misc/de...0waveform2.mp3 with a similar specal analysis http://www.guitar-dreams.com/misc/de...0waveform2.jpg Any idea what is going on here? In both cases, the spectral peaks are at 50Hz which of course is no coincidence. I would be tempted to think it has something to do with the step down transformer I am using on my US gear. But in this apartment, if I turn on a stereo, I hear 50Hz coming through the speakers regardless of the transformer. I feel like I am just doomed in this apartment. I hear 50Hz everywhere. The fridge, etc,etc. |
#9
|
|||
|
|||
Can you explain this 50Hz hum??
Invert the phase.
"me" wrote in message s.com... This is so annoying. The only thing I have on are the computer and mixer (and hence the power transformer I use here in Germany for my US gear). The mixer's first two channel inserts are connected to delta1010 ins1/2. There are two mics coming into those channels, but even with the mic cables unplugged and trim all the way down, the delta monitor shows the following: www.guitar-dreams.com/misc/delta1010problem1.jpg If I unplug the inserts it goes away. The recorded audio is http://www.guitar-dreams.com/misc/de...0waveform1.mp3 The spectrum analysis shows http://www.guitar-dreams.com/misc/de...0waveform1.jpg So, if I take the unplugged insert and touch it against any jack on the mixer, the input level on the delta then rises back to the level shown in the picture above (first one). I then touched it against one of the screws that is holding the delta on my rack and suddenly both delta ins 1/2 input levels dropped down. Not completely though. There is still a waveform there http://www.guitar-dreams.com/misc/de...0waveform2.mp3 with a similar specal analysis http://www.guitar-dreams.com/misc/de...0waveform2.jpg Any idea what is going on here? In both cases, the spectral peaks are at 50Hz which of course is no coincidence. I would be tempted to think it has something to do with the step down transformer I am using on my US gear. But in this apartment, if I turn on a stereo, I hear 50Hz coming through the speakers regardless of the transformer. I feel like I am just doomed in this apartment. I hear 50Hz everywhere. The fridge, etc,etc. |
#10
|
|||
|
|||
Can you explain this 50Hz hum??
Mike Dobony wrote: I had the same problem and it was the cable. Try a new cable. We have the 60Hz hum here. It's "10 louder". But seriously, it does sound like it's the cable, especially if there's stereo mini involved. Don |
#11
|
|||
|
|||
Can you explain this 50Hz hum??
Mike Dobony wrote: I had the same problem and it was the cable. Try a new cable. We have the 60Hz hum here. It's "10 louder". But seriously, it does sound like it's the cable, especially if there's stereo mini involved. Don |
#12
|
|||
|
|||
Can you explain this 50Hz hum??
It happens with a variety of cables.
-brian "Mike Dobony" wrote in message ... "me" wrote in message s.com... I know about ground loops when it comes to driving 2 amps with one guitar, and I know how that problem is solved. I feel this is different. I have never dealt with a problem that involves the computer. -brian It is no different with a computer. However, you mentioned it is associated with an insert. I had the same problem and it was the cable. Try a new cable. -- Mike D. www.stopassaultnow.org Remove .spamnot to respond by email "Chris Hornbeck" wrote in message ... On Mon, 27 Oct 2003 20:36:49 GMT, "me" wrote: This is so annoying. The only thing I have on are the computer and mixer This sounds like a classic case of ground loop. First read the FAQ, then check back. BTW, it's called a loop because the ground path is one turn of a big transformer. If you break that path, no current can flow; hence, no hum. Good fortune, Chris Hornbeck new email address --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.532 / Virus Database: 326 - Release Date: 10/27/2003 |
#13
|
|||
|
|||
Can you explain this 50Hz hum??
Invert the phase of what?
-brian "Walter Chan" wrote in message ... Invert the phase. "me" wrote in message s.com... This is so annoying. The only thing I have on are the computer and mixer (and hence the power transformer I use here in Germany for my US gear). The mixer's first two channel inserts are connected to delta1010 ins1/2. There are two mics coming into those channels, but even with the mic cables unplugged and trim all the way down, the delta monitor shows the following: www.guitar-dreams.com/misc/delta1010problem1.jpg If I unplug the inserts it goes away. The recorded audio is http://www.guitar-dreams.com/misc/de...0waveform1.mp3 The spectrum analysis shows http://www.guitar-dreams.com/misc/de...0waveform1.jpg So, if I take the unplugged insert and touch it against any jack on the mixer, the input level on the delta then rises back to the level shown in the picture above (first one). I then touched it against one of the screws that is holding the delta on my rack and suddenly both delta ins 1/2 input levels dropped down. Not completely though. There is still a waveform there http://www.guitar-dreams.com/misc/de...0waveform2.mp3 with a similar specal analysis http://www.guitar-dreams.com/misc/de...0waveform2.jpg Any idea what is going on here? In both cases, the spectral peaks are at 50Hz which of course is no coincidence. I would be tempted to think it has something to do with the step down transformer I am using on my US gear. But in this apartment, if I turn on a stereo, I hear 50Hz coming through the speakers regardless of the transformer. I feel like I am just doomed in this apartment. I hear 50Hz everywhere. The fridge, etc,etc. |
#14
|
|||
|
|||
Can you explain this 50Hz hum??
You have a grounding problem. The three types are "not enough ground,"
"too much ground," or "mislocated ground." To see if you have "not enough ground," just connect a wire from the chassis of the mixer to the chassis of the Delta1010. If that solves the problem, then you can fix it "for real" by figuring out why you weren't getting a solid ground connection in your audio cable. To see if you have "too much ground," you need to disconnect a ground wire someplace. The safest way to do this is to use an audio cable with its shield cut at one end. It's not considered safe to lift the ground on the power cable. If neither of these is your problem, then you're in a tough spot because you can't do much about the 3rd possibility. My suspicion is that the equipment is expecting to see a solid ground connection through the power cable, but that you have inadvertently lifted that ground by using a 220:110 stepdown transformer that is ungrounded. ulysses In article m, me wrote: This is so annoying. The only thing I have on are the computer and mixer (and hence the power transformer I use here in Germany for my US gear). The mixer's first two channel inserts are connected to delta1010 ins1/2. There are two mics coming into those channels, but even with the mic cables unplugged and trim all the way down, the delta monitor shows the following: www.guitar-dreams.com/misc/delta1010problem1.jpg If I unplug the inserts it goes away. The recorded audio is http://www.guitar-dreams.com/misc/de...0waveform1.mp3 The spectrum analysis shows http://www.guitar-dreams.com/misc/de...0waveform1.jpg So, if I take the unplugged insert and touch it against any jack on the mixer, the input level on the delta then rises back to the level shown in the picture above (first one). I then touched it against one of the screws that is holding the delta on my rack and suddenly both delta ins 1/2 input levels dropped down. Not completely though. There is still a waveform there http://www.guitar-dreams.com/misc/de...0waveform2.mp3 with a similar specal analysis http://www.guitar-dreams.com/misc/de...0waveform2.jpg Any idea what is going on here? In both cases, the spectral peaks are at 50Hz which of course is no coincidence. I would be tempted to think it has something to do with the step down transformer I am using on my US gear. But in this apartment, if I turn on a stereo, I hear 50Hz coming through the speakers regardless of the transformer. I feel like I am just doomed in this apartment. I hear 50Hz everywhere. The fridge, etc,etc. |
#15
|
|||
|
|||
Can you explain this 50Hz hum??
Brian Huether wrote: It happens with a variety of cables. I wonder if there's a short in back of the panel, then. Don |
#16
|
|||
|
|||
Can you explain this 50Hz hum??
I don't know if you have looked into this, but is your computer connected
to the internet by cable or phone? Does the hum go away when you physically disconnect? rob R. me wrote: This is so annoying. The only thing I have on are the computer and mixer (and hence the power transformer I use here in Germany for my US gear). The mixer's first two channel inserts are connected to delta1010 ins1/2. There are two mics coming into those channels, but even with the mic cables unplugged and trim all the way down, the delta monitor shows the following: www.guitar-dreams.com/misc/delta1010problem1.jpg If I unplug the inserts it goes away. The recorded audio is http://www.guitar-dreams.com/misc/de...0waveform1.mp3 The spectrum analysis shows http://www.guitar-dreams.com/misc/de...0waveform1.jpg So, if I take the unplugged insert and touch it against any jack on the mixer, the input level on the delta then rises back to the level shown in the picture above (first one). I then touched it against one of the screws that is holding the delta on my rack and suddenly both delta ins 1/2 input levels dropped down. Not completely though. There is still a waveform there http://www.guitar-dreams.com/misc/de...0waveform2.mp3 with a similar specal analysis http://www.guitar-dreams.com/misc/de...0waveform2.jpg Any idea what is going on here? In both cases, the spectral peaks are at 50Hz which of course is no coincidence. I would be tempted to think it has something to do with the step down transformer I am using on my US gear. But in this apartment, if I turn on a stereo, I hear 50Hz coming through the speakers regardless of the transformer. I feel like I am just doomed in this apartment. I hear 50Hz everywhere. The fridge, etc,etc. |
#17
|
|||
|
|||
Can you explain this 50Hz hum??
In article ,
Justin Ulysses Morse wrote: You have a grounding problem. The three types are "not enough ground," "too much ground," or "mislocated ground." SNIP If neither of these is your problem, then you're in a tough spot because you can't do much about the 3rd possibility. I think that sometimes the Cable as in cable TV or Broadband connection jack has it's ground elsewhere, try pulling that if you have one ... -- Joakim Wendel Remove obvious mail JUNK block for mail reply. My homepage : http://violinist.nu |
#18
|
|||
|
|||
Can you explain this 50Hz hum??
I don't know your step-down transformer, but could it be operating non-linearly
(perhaps saturating) and sending 50-Hz-modulated trash in through a power supply? me wrote: This is so annoying. The only thing I have on are the computer and mixer |
#19
|
|||
|
|||
Can you explain this 50Hz hum??
"Brian Huether" wrote in message ... Invert the phase of what? -brian In an unbalanced situation, the 'hot' and 'ground'. In a balanced situation the 'hot' and 'cold'. unbalanced: RCA. balanced: XLR - swap pins 2 and 3 balanced: TRS - swap ring and tip. Alternatively, ground any unused pins on a balanced connector (i.e. solder pin 2 (or pin 3) to pin 1 on the XLR) I'd do it with a separate adapter (always have them handy). "Walter Chan" wrote in message ... Invert the phase. "me" wrote in message s.com... This is so annoying. The only thing I have on are the computer and mixer (and hence the power transformer I use here in Germany for my US gear). The mixer's first two channel inserts are connected to delta1010 ins1/2. There are two mics coming into those channels, but even with the mic cables unplugged and trim all the way down, the delta monitor shows the following: www.guitar-dreams.com/misc/delta1010problem1.jpg If I unplug the inserts it goes away. The recorded audio is http://www.guitar-dreams.com/misc/de...0waveform1.mp3 The spectrum analysis shows http://www.guitar-dreams.com/misc/de...0waveform1.jpg So, if I take the unplugged insert and touch it against any jack on the mixer, the input level on the delta then rises back to the level shown in the picture above (first one). I then touched it against one of the screws that is holding the delta on my rack and suddenly both delta ins 1/2 input levels dropped down. Not completely though. There is still a waveform there http://www.guitar-dreams.com/misc/de...0waveform2.mp3 with a similar specal analysis http://www.guitar-dreams.com/misc/de...0waveform2.jpg Any idea what is going on here? In both cases, the spectral peaks are at 50Hz which of course is no coincidence. I would be tempted to think it has something to do with the step down transformer I am using on my US gear. But in this apartment, if I turn on a stereo, I hear 50Hz coming through the speakers regardless of the transformer. I feel like I am just doomed in this apartment. I hear 50Hz everywhere. The fridge, etc,etc. |
Reply |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Explain me this | Audio Opinions | |||
TS/TRS balanced/unbalanced can someone explain | General | |||
60 hz cassette deck on 50hz power? | General | |||
60 hz cassette deck on 50hz power? | General | |||
Reverb & EQ and "damping" etc .. please explain .. | Pro Audio |