Alright, I haven't the kit I'd like to have, but I promised someone I'd record some tunes for them. I have on hand at the moment only a few microphones, nothing like what I wish I had. For example, top down, I have a pzm boundary mic, a tip-of-the-little-finger electret lapel mic and a Labtec computer mic. I have worse, but these three will do for now. As intermediary between computer and microphone I have an Edirol UA-4FX, which I mostly use to process old field recordings, LPs and tape, for which it has worked charmingly. For recording it has plug access for 1/4" mic/instrument and 1/8" powered, as well as being able to take a 3-pin...
Now, the problem I can't shake, and I admit that most of my background will be live sound (in the past somewhere, so I'm rusty) and I'm familiar with the fact that microphones, especially powered ones, which all three are, two battery and one USB, have their own noise, low noise, often beyond the perception of old ears. But what I am consistently getting is a lot of background noise, grumble, rumble. The male plugs are 1/4" & 1/8" & USB respectively...
I've got the meters set to read between -78 to 0 db. The floor of this rumble comes up to about midway and it's driving me nuts. It doesn't matter what microphone I use. If I lower the level then I lose the recorded signal too. If I raise the recorded signal so I can hear it, the rumble follows. It is almost like a recording made off of a really bad bit of vinyl, like those awful vinyl inserts that used to come in music books... It is also similar to the rumble of a cassette player, such as when picking up its own motor while recording, only louder... I then tried using an old mono transcription tape recorder ~ and oddly it seems to be doing the same thing. So the source of the interference seems to be the powered microphones. Maybe I'm used to better microphones than this. I've done recording in the past, better equipment, but no problems like this, so no experience with this problem before.
Aside from the craic, does anybody out there have any idea of what the problem might be? "Shight equipment" is a reasonable answer, but I've had better results with bad equipment in the past...
I've an Edirol UA20 usb interface that is noisy if I use it at 'mic' sensitivity. Its not a rumble tho - more of a digital tweet!! Its fine at line level.
I got round the problem by using a small mixing desk with mic preamps to boost the signal from the mics, then sending the signals from the desk into different ports on the edirol (you could pan hard left for one, hard right for the second (and then use left and right main outs) and use an aux send for the third).
This solution does require a mixer, but maybe the edirols are inherently a bit noisy with mic signals.
Gotta wonder if the rumble is a real sound you are picking up and which is perhaps being amplified by resonance in say the microphone stand, or surface the mic is placed on. Do you get this when the recording kit is set up somewhere else completely, or if the mics are mounted differently?
Have you tried using a different intermediary between the mics and the computer? Also it might be just one mic giving you trouble you might try recording with only one mic at a time to single out the problem.
I ran cabling out to a room that allowed me to isolate it all from most outside noise, rooms all around, and I tried different set-ups as far as microphone placement, avoiding the speaker cabinets and stereo in that room ~ same problem. The pzm and electret are battery powered. I admit I've been spoiled, in the past working with AKG & Neumann microphones and the full kit, including a decent mixing board. The mics on hand were from other work, the boundary for recording lectures and the electret from the deep dark past when it was used for its portability as an interview mic. With these two microphones ending up producing a similar result as far as the noise, I had to wonder if there was some power source nearby, some source for a signal that might be picked up on the cables. These are not the robust cables I've worked with in the past, hardly well shielded, 1/16" on the old lapel mic and just under 1/8" on the boundary pzm...
I'm going to go ahead and try some cheaper kit I've got, an old ball dynamic and maybe some other items too.
The intermediary is a good idea, a mixing board with pans. I also could rig things up and drive the signal through a set equalizers, such as parametrics... But, face wringling and brow furrowing worse than usual in a wry squint, I just feel like it shouldn't be giving me this kind of trouble. It has been a long time since I did any live recording, in this sense, but this low hum/rumble has me flumuxed...
I pulled out my print resources to pour over possibilities, but nothing seemed to ring true there, not yet anyway, and I checked some online as well. I have to confess too that past recording of this sort, not field, were in the main group efforts, or at least two of us present to bounce ideas off of...
Thanks for the prompt responses, appreciated.
I was worried someone like Danny or Dow might blame it on my tinnitus. Just to answer that possible suggestion ~ no, my tinnitus is in a different key from this...
Sometimes you can get that sort of rumbling sound from poor electrical contact (say in a battery-powered mic) but if you're getting that trouble with more than one mic then not sure.
One other issue is: if your rumble is somewhere between -78dB and 0dBm, depending on your meter scale, that's something like -39dB (possibly!!) which is not necessarily bad for a domestic quality mic assuming the "wanted" sound takes the meter reading right up to 0dB. If you're seeing stuff happening down around -40dB below the signal, that's not too bad (but not fantastic) for a domestic mic.
Ground loops can be an issue, but another source might be the electronics picking up noise. I have a soundcraft mixer that's particularly bad in this respect. Or it could be a small transformer somewhere (one of those little ones which give out a low voltage for powering equipment) which is putting noise into your system.
Proper xlr (balanced) cables with balanced mics and balanced inputs would eliminate most things other than the noise contributed by the mic or the input you're feeding it into.
Rereading your initial post, it sounds a lot like a poor connection somewhere in the analogue signal path, perhaps within your Edirol box. Solder connections, for example, can go a bit iffy over a long period, and these would be more noticeable with mic-level signals than they would with the line output from a tape machine, where you don't have to amplify anything much.
Thanks, I think your on to something Mark. I had this inkling I'd come across a similar sound before. Your comments made the link. It was with solder failure cable to plug, and this has a similar sound, though constant. You're right about the level, but the source, me, isn't overriding the interference, not enough to make for a decent recording. These are hoped for back-up to help some students, and one of them is involved as a 'distant learner'. I'm going to chase up some studio junkies this weekend and see if I can get some more ideas and maybe borrow some kit.
Another source for similar aggravation in the past was with plugs that didn't quite fit, they didn't make a clean contact. That just came to mind too. But as well, these are old mics and that means the cabling is old too. I have another memory your comment raised which was with a cable once that had had failure down the line. I'm not sure what had caused it originally but there was a break inside the cable that didn't show oustide, you had to feel for it... I also wonder if there might have been a fault caused when a certain someone, me, tried running a battery powered mic through the 'powered input', both having 1/8" plugs and not thinking clearly... What was weird is I ended up with a clean floor and what looked like a decent signal response on the Edirol box, but nothing recorded. It fooled me, but I quickly removed the plug when I realized my mistake...
It's the fool in me that wants these recorings to be reasonably clean for the intended recipients. It's bad enough it's me, the least I can do is give them something that won't do too much damage to their ears...
If the problem is in the sockets, you could try pushing the plug in and out a few times - but it sounds as if it could be the box or the cable. At least it would eliminate one potential source - plugging things in and out will clean any connections a bit. Good luck in your quest to find the problem!
Just replied at length but post got swallowed... If this double posts I apologize now.... Maybe bit obvious but Are your batteries fresh? could be a gain staging issue..weak batteries = low signal meaning you have to over crank the gain thus bringing out low level noise present on all mics and cables. May well be dirty , oxidized or greasy jack plug. this can produce that rumbling " wind noise on a mic" type sound even when the plug is not being moved about. its cos of bad contact. Another strong possibility for the type of noise you describe could be your cable oxidized inside or with microfractures in its core.(through age, coiling / uncoiling). Mark's right ,mic level signals are much more critical regarding noise cos of the massive gain which is applied. I know you said it was on all mics but did you try them all one at a time whist unplugging the others? Good point someone made about isolating the problem . Doubt is ground loop as this is usually a clean but annoying sounding low hum....does the noise get worse when you wiggle jacks./cables.? if yes probably is bad contact / microfractures respectively. Try the XLR (3 pin) input (combo sockets on the edirol, right?) with a mic and cable you KNOW is ok then see how that goes, then you will know if problem is on your interface or your original mics/cables Oh.... I just thought, you are using a 1/4" mic input , these come in two flavours balanced and unbalanced, if it is expecting a balanced signal and you send it an unbalanced signal this would account for serious signal/noise ratio issues .you would get a very weak signal with plenty of gain noise being added as you try to get the levels up.. maybe should check specs to see which type of signal format your 1/4" input is expecting. Anyway, best of luck , Hope you get it sorted.. I feel your pain!
Damn you guys are great. I had been thinking that too. In this visit to the studio jocks I was also going to check out new batteries. It's not beig expense to give that a try too... The jacks are all well maintained and clean... but as Mark mentioned, there is a nod of familiarity about this sound and previous problems with dirty contacts. However, I haven't generally used battery mics before, since any that needed power drew it from phantom sources, the board for example... Yes, the cables are old...
I have tried the mics each individually, standard practice... It doesn't get worse wiggling the cables Also a good point I was planning to exercise ~ testing with XLR...
Great comments all. You're gems... Thanks for the consideration... At least sharing this has lessened my irritability and frustration. It's true in this case, a worry shared is halved... You've put me in a better spirit and from there I can deal with this in a reasoned way, much appreciated...
...or you could play the cassette to me, I could play it on the harp, and then play it down the phone to someone else! Not sure if de Selby is being serious here!! but I love the idea of a musical version of that children's game where you pass a phrase between people and see where it ends up.
Dirty Floors ~ Grumble, Rumble
Dirty Floors ~ Grumble, Rumble
Alright, I haven't the kit I'd like to have, but I promised someone I'd record some tunes for them. I have on hand at the moment only a few microphones, nothing like what I wish I had. For example, top down, I have a pzm boundary mic, a tip-of-the-little-finger electret lapel mic and a Labtec computer mic. I have worse, but these three will do for now. As intermediary between computer and microphone I have an Edirol UA-4FX, which I mostly use to process old field recordings, LPs and tape, for which it has worked charmingly. For recording it has plug access for 1/4" mic/instrument and 1/8" powered, as well as being able to take a 3-pin...
Now, the problem I can't shake, and I admit that most of my background will be live sound (in the past somewhere, so I'm rusty) and I'm familiar with the fact that microphones, especially powered ones, which all three are, two battery and one USB, have their own noise, low noise, often beyond the perception of old ears. But what I am consistently getting is a lot of background noise, grumble, rumble. The male plugs are 1/4" & 1/8" & USB respectively...
I've got the meters set to read between -78 to 0 db. The floor of this rumble comes up to about midway and it's driving me nuts. It doesn't matter what microphone I use. If I lower the level then I lose the recorded signal too. If I raise the recorded signal so I can hear it, the rumble follows. It is almost like a recording made off of a really bad bit of vinyl, like those awful vinyl inserts that used to come in music books... It is also similar to the rumble of a cassette player, such as when picking up its own motor while recording, only louder... I then tried using an old mono transcription tape recorder ~ and oddly it seems to be doing the same thing. So the source of the interference seems to be the powered microphones. Maybe I'm used to better microphones than this. I've done recording in the past, better equipment, but no problems like this, so no experience with this problem before.
Aside from the craic, does anybody out there have any idea of what the problem might be? "Shight equipment" is a reasonable answer, but I've had better results with bad equipment in the past...
Perplexed and frustrated ~ 'c'
# Posted on April 30th 2008 by ceolachan
Re: Dirty Floors ~ Grumble, Rumble
I've an Edirol UA20 usb interface that is noisy if I use it at 'mic' sensitivity. Its not a rumble tho - more of a digital tweet!! Its fine at line level.
I got round the problem by using a small mixing desk with mic preamps to boost the signal from the mics, then sending the signals from the desk into different ports on the edirol (you could pan hard left for one, hard right for the second (and then use left and right main outs) and use an aux send for the third).
This solution does require a mixer, but maybe the edirols are inherently a bit noisy with mic signals.
# Posted on April 30th 2008 by bodatcha
Re: Dirty Floors ~ Grumble, Rumble
just read your bit about using the tape recorder...durrr.....strange that you should get the same problem with all the mics.
# Posted on April 30th 2008 by bodatcha
Re: Dirty Floors ~ Grumble, Rumble
perhaps a ground loop? A DI box would sort that out....Are the devices powered from the same plug socket?
# Posted on April 30th 2008 by jig
Re: Dirty Floors ~ Grumble, Rumble
Gotta wonder if the rumble is a real sound you are picking up and which is perhaps being amplified by resonance in say the microphone stand, or surface the mic is placed on. Do you get this when the recording kit is set up somewhere else completely, or if the mics are mounted differently?
Liam
# Posted on April 30th 2008 by billiamconkey
Re: Dirty Floors ~ Grumble, Rumble
Have you tried using a different intermediary between the mics and the computer? Also it might be just one mic giving you trouble you might try recording with only one mic at a time to single out the problem.
# Posted on April 30th 2008 by Fellenbaum
Re: Dirty Floors ~ Grumble, Rumble
I ran cabling out to a room that allowed me to isolate it all from most outside noise, rooms all around, and I tried different set-ups as far as microphone placement, avoiding the speaker cabinets and stereo in that room ~ same problem. The pzm and electret are battery powered. I admit I've been spoiled, in the past working with AKG & Neumann microphones and the full kit, including a decent mixing board. The mics on hand were from other work, the boundary for recording lectures and the electret from the deep dark past when it was used for its portability as an interview mic. With these two microphones ending up producing a similar result as far as the noise, I had to wonder if there was some power source nearby, some source for a signal that might be picked up on the cables. These are not the robust cables I've worked with in the past, hardly well shielded, 1/16" on the old lapel mic and just under 1/8" on the boundary pzm...
I'm going to go ahead and try some cheaper kit I've got, an old ball dynamic and maybe some other items too.
The intermediary is a good idea, a mixing board with pans. I also could rig things up and drive the signal through a set equalizers, such as parametrics... But, face wringling and brow furrowing worse than usual in a wry squint, I just feel like it shouldn't be giving me this kind of trouble. It has been a long time since I did any live recording, in this sense, but this low hum/rumble has me flumuxed...
I pulled out my print resources to pour over possibilities, but nothing seemed to ring true there, not yet anyway, and I checked some online as well. I have to confess too that past recording of this sort, not field, were in the main group efforts, or at least two of us present to bounce ideas off of...
Thanks for the prompt responses, appreciated.
I was worried someone like Danny or Dow might blame it on my tinnitus. Just to answer that possible suggestion ~ no, my tinnitus is in a different key from this...
# Posted on April 30th 2008 by ceolachan
The boundary was for lectures and seminars ~ but it had to produce a clean enough sound for transcription, which it used to...
# Posted on April 30th 2008 by ceolachan
Re: Dirty Floors ~ Grumble, Rumble
Sometimes you can get that sort of rumbling sound from poor electrical contact (say in a battery-powered mic) but if you're getting that trouble with more than one mic then not sure.
One other issue is: if your rumble is somewhere between -78dB and 0dBm, depending on your meter scale, that's something like -39dB (possibly!!) which is not necessarily bad for a domestic quality mic assuming the "wanted" sound takes the meter reading right up to 0dB. If you're seeing stuff happening down around -40dB below the signal, that's not too bad (but not fantastic) for a domestic mic.
Ground loops can be an issue, but another source might be the electronics picking up noise. I have a soundcraft mixer that's particularly bad in this respect. Or it could be a small transformer somewhere (one of those little ones which give out a low voltage for powering equipment) which is putting noise into your system.
Proper xlr (balanced) cables with balanced mics and balanced inputs would eliminate most things other than the noise contributed by the mic or the input you're feeding it into.
# Posted on April 30th 2008 by Mark Harmer
Re: Dirty Floors ~ Grumble, Rumble
Rereading your initial post, it sounds a lot like a poor connection somewhere in the analogue signal path, perhaps within your Edirol box. Solder connections, for example, can go a bit iffy over a long period, and these would be more noticeable with mic-level signals than they would with the line output from a tape machine, where you don't have to amplify anything much.
# Posted on April 30th 2008 by Mark Harmer
Re: Dirty Floors ~ Grumble, Rumble
Thanks, I think your on to something Mark. I had this inkling I'd come across a similar sound before. Your comments made the link. It was with solder failure cable to plug, and this has a similar sound, though constant. You're right about the level, but the source, me, isn't overriding the interference, not enough to make for a decent recording. These are hoped for back-up to help some students, and one of them is involved as a 'distant learner'. I'm going to chase up some studio junkies this weekend and see if I can get some more ideas and maybe borrow some kit.
Another source for similar aggravation in the past was with plugs that didn't quite fit, they didn't make a clean contact. That just came to mind too. But as well, these are old mics and that means the cabling is old too. I have another memory your comment raised which was with a cable once that had had failure down the line. I'm not sure what had caused it originally but there was a break inside the cable that didn't show oustide, you had to feel for it... I also wonder if there might have been a fault caused when a certain someone, me, tried running a battery powered mic through the 'powered input', both having 1/8" plugs and not thinking clearly... What was weird is I ended up with a clean floor and what looked like a decent signal response on the Edirol box, but nothing recorded. It fooled me, but I quickly removed the plug when I realized my mistake...
It's the fool in me that wants these recorings to be reasonably clean for the intended recipients. It's bad enough it's me, the least I can do is give them something that won't do too much damage to their ears...
# Posted on April 30th 2008 by ceolachan
Re: Dirty Floors ~ Grumble, Rumble
If the problem is in the sockets, you could try pushing the plug in and out a few times - but it sounds as if it could be the box or the cable. At least it would eliminate one potential source - plugging things in and out will clean any connections a bit. Good luck in your quest to find the problem!
Mark
# Posted on April 30th 2008 by Mark Harmer
Re: Dirty Floors ~ Grumble, Rumble
Just replied at length but post got swallowed... If this double posts I apologize now.... Maybe bit obvious but Are your batteries fresh? could be a gain staging issue..weak batteries = low signal meaning you have to over crank the gain thus bringing out low level noise present on all mics and cables. May well be dirty , oxidized or greasy jack plug. this can produce that rumbling " wind noise on a mic" type sound even when the plug is not being moved about. its cos of bad contact. Another strong possibility for the type of noise you describe could be your cable oxidized inside or with microfractures in its core.(through age, coiling / uncoiling). Mark's right ,mic level signals are much more critical regarding noise cos of the massive gain which is applied. I know you said it was on all mics but did you try them all one at a time whist unplugging the others? Good point someone made about isolating the problem . Doubt is ground loop as this is usually a clean but annoying sounding low hum....does the noise get worse when you wiggle jacks./cables.? if yes probably is bad contact / microfractures respectively. Try the XLR (3 pin) input (combo sockets on the edirol, right?) with a mic and cable you KNOW is ok then see how that goes, then you will know if problem is on your interface or your original mics/cables Oh.... I just thought, you are using a 1/4" mic input , these come in two flavours balanced and unbalanced, if it is expecting a balanced signal and you send it an unbalanced signal this would account for serious signal/noise ratio issues .you would get a very weak signal with plenty of gain noise being added as you try to get the levels up.. maybe should check specs to see which type of signal format your 1/4" input is expecting. Anyway, best of luck , Hope you get it sorted.. I feel your pain!
# Posted on April 30th 2008 by peter wsll
Re: Dirty Floors ~ Grumble, Rumble
Damn you guys are great. I had been thinking that too. In this visit to the studio jocks I was also going to check out new batteries. It's not beig expense to give that a try too... The jacks are all well maintained and clean... but as Mark mentioned, there is a nod of familiarity about this sound and previous problems with dirty contacts. However, I haven't generally used battery mics before, since any that needed power drew it from phantom sources, the board for example... Yes, the cables are old...
I have tried the mics each individually, standard practice... It doesn't get worse wiggling the cables Also a good point I was planning to exercise ~ testing with XLR...
Great comments all. You're gems... Thanks for the consideration... At least sharing this has lessened my irritability and frustration. It's true in this case, a worry shared is halved... You've put me in a better spirit and from there I can deal with this in a reasoned way, much appreciated...
# Posted on April 30th 2008 by ceolachan
Re: Dirty Floors ~ Grumble, Rumble
There's a great expression where I used to work:
"A problem shared is the blame halved"
Always loved that one.
# Posted on April 30th 2008 by Mark Harmer
Re: Dirty Floors ~ Grumble, Rumble
Yeah, that got a chuckle out of me too, but all blame here is confined to this side of the digital divide...
# Posted on May 1st 2008 by ceolachan
Re: Dirty Floors ~ Grumble, Rumble
I can help you out with this. Play the tunes down the phone to me. I'll pick them up on my Sony Walkman and send you the cassette.
# Posted on May 1st 2008 by de Selby
Re: Dirty Floors ~ Grumble, Rumble
...or you could play the cassette to me, I could play it on the harp, and then play it down the phone to someone else! Not sure if de Selby is being serious here!! but I love the idea of a musical version of that children's game where you pass a phrase between people and see where it ends up.
# Posted on May 1st 2008 by Mark Harmer
Re: Dirty Floors ~ Grumble, Rumble
Chinese whispers ? Yeah, that sounds like fun...
# Posted on May 1st 2008 by wolfbird
Re: Dirty Floors ~ Grumble, Rumble
We've done it a few times via this site Mark, starting as a discussion...
Group efforts ~
jig: James and the Giant Peach / Peach Schnapps
http://www.thesession.org/tunes/display.php/4605
jig: Sauerkraut, Wurst Und Kartoffelbrei
http://www.thesession.org/tunes/display/7786
# Posted on May 1st 2008 by ceolachan