Help with 'Hiss' on Home Voice Recordings!

[sprout21]

Hello All,

I am new to the site and probably majorly lacking in the abundance of technical knowledge I imagine most of the users here to have...Therefore, please find my technical query in simplified 'newbie' terms:

I have a Behringer C3 Mic connected via Gold XLR to an original MBox, then via USB into laptop where I am using Protools to record voiceover clips.
I have been having constant issues with hiss/static/feedback/white noise on my recordings. (Previously used a Art MP Preamp straight into the laptop until I came to the conclusion that the lack of an audio interface - other than rubbish RealTek HD Soundcard - was the reason I was getting the hiss.)
Since purchasing the MBox in place of the stand-alone Preamp, the sound quality seems better, however I am finding getting the balance difficult between lowering the input volume on my Mbox to reduce the hiss - but then struggling to retain a high volume of the recording to get that warm, narrative sound with enough volume to avoid as much normalising/amplifying in post, (that in affect brings the noise up too.) Do you have any suggestions for abolishing the hiss? - other than just using noise removal software in post/sound gate -

And...

Being closer to the mic and speaking louder as a result of the unwanted noise is also bringing some unwanted vibration and pops into my recordings. I have a pop shield to prevent plosive issues but want a slip-on windshield instead to completely cover the mic head...Will this help to resolve the situation when combined with the Spider Shock Mount SP01 that I have just purchased? And if so, does anyone know what WindShield (and corresponding dimensions) fits snuggly on the C3?

Thanks in advance for any help whatsoever as I have been seeking advice and scrolling the internet over this for weeks Please no product criticisms as I know all of my equipment is very low-end and budget - I have just read elsewhere that you still should be able to get clear, 'noise-free' recordings using the C3 Mic with enough volume and warmth to avoid lots of editing in post...

J

 

[gecko zzed]

The cause is most likely to be found somewhere between mike and USB, i.e. the culprits could be the mike itself, the XLR lead or the Mbox.

Some first things to check are: is the phantom powered switched on for the mike? Have you tried a different XLR lead?

With the set up you have, you should be able to get a good, clean, strong signal. You should not need to cover the mike head.

 

[Bobbsy]

Most Behringer C3s are pretty good but the quality can be variable. I've heard of the odd one that is just inherently noisy.

Can you find somebody else who could plug your mic into a mixer or decent sound card to check it--and if it's noisy Behringer are generally good about exchanging goods if they're within the warranty period.

Beyond that, gecko zzed offers some good suggestions, though hiss is generally a product of active electronics, not cables.

Bob

 

[witzendoz]

Maybe an earth loop on the usb? to eliminate this, does the noise reduce when running the laptop on the battery unplugging the power lead?

Cheers
Alan

 

[sprout21]

Thanks for reply

The cause is most likely to be found somewhere between mike and USB, i.e. the culprits could be the mike itself, the XLR lead or the Mbox.

Some first things to check are: is the phantom powered switched on for the mike? Have you tried a different XLR lead?

With the set up you have, you should be able to get a good, clean, strong signal. You should not need to cover the mike head.

Thanks for replying and for the info
The phantom power is switched on, yes. I don't think you can use the mic without it. Re: The XLR lead - I bought a new gold plated one as I thought that maybe the cause, however since setting it up there is no change.
Re: not covering the mic head, that is good and what I thought should be the case. I was looking into that area just because I am positioning myself closer & closer to the mic in order to reduce the 'noise' and that is causing vibration when speaking loud. Will the spider shock mount solve that on its own as I am still using a pop shield?

 

[sprout21]

**********************

 

[sprout21]

Most Behringer C3s are pretty good but the quality can be variable. I've heard of the odd one that is just inherently noisy.

Can you find somebody else who could plug your mic into a mixer or decent sound card to check it--and if it's noisy Behringer are generally good about exchanging goods if they're within the warranty period.

Beyond that, gecko zzed offers some good suggestions, though hiss is generally a product of active electronics, not cables.

Bob

Thanks for your reply and info - that is nice to hear as they are pretty slated by some people.

I will have to try and find someone who does so I can test it as good suggestion. Could it be dust on the mic or something? If so, is there a way of cleaning it using a hoover or compressed air etc? I know I need to eliminate each source in the chain so if not the XLR cable or the Mbox (which was tested when I bought it - and the noise was present before in my previous setup) then could very well be the mic...

I will try dig out my warranty...

 

[sprout21]

Thanks for reply and info

Maybe an earth loop on the usb? to eliminate this, does the noise reduce when running the laptop on the battery unplugging the power lead?

Cheers
Alan

Hi Alan,

That was something I experimented with before as I do get feedback/noise on another amp I use when doing DJ sets. Once I removed the power cable, it stopped. However, that was more of an electrical buzzing than the 'white noise' I get on my voice recordings - sounding just like a TV on with no signal...

How would I go about earth looping the USB? I will try another USB cable too to see if that is where the problem lies...

Does it matter if the XLR cable runs under my bed along a carpetted floor from the MBox to the Mic? Could that cause feedback? And also does it matter if the Mbox sits next to the laptop due to the USB cable being fairly short? The noise was present before I got the MBox though so leads me to think that isn't the issue...

Thanks in advance of more help and advice

 

[JB's Studio]

I don't have a MBox. I have a M-Audio Fast Track Pro. I have noticed that if I turn up the input levels on the FTP that after a certain point about 1/8th turn below max I get bad hiss from the FTP. That happened when I was using the pad on the mic and had to make up the gain there. I solved the problem by getting a separate mic preamp. Now I can run the levels on the FTP around noon and adjust the gain on the preamp and voila! no more hiss. Mic Preamps can go cheap to expensive (low end ART, mid Presonus, and after that there's a big price jump). What you pay will depend upon your use, and budget. You probably can get by just fine with a $70 tube preamp. Check Sweetwater and when you order (if) tell your sales rep what you're doing and what your budget is.

 

[sjjohnston]

My only thought:

Usually hiss of the type you describe (high-pitched, "white" noisesque) is just the ordinary noise that's present - to some degree - in all audio signal chains. Mis-wiring, broken stuff and interference more often produces buzzes, hums, crackles, distortion and (of course) silence.

How much gain are you using in the preamp? If the mic signal is, for some reason, very low, the huge amount of preamp gain necessary to get up to a line-level signal would almost certainly produce audible hiss. From your own question, it sounds like you're fully aware of that, and are already doing what you can to get the signal from the mic as hot as possible. Just to mention another incredibly obvious issue: make sure you're not padding the mic signal. I'm not entirely sure how the MBox works, but I think you can activate a pad by pulling out the gain knob. Don't do that.

I suppose the most likely culprits are something like:
- the mic: something's wrong with it, causing it not to produce as hot a signal as it should;
- the mic: something's wrong with its internal preamp (condensors all have one), which is itself just plain noisy;
- the preamp: somewhere in its internal signal chain it's dropping the signal level in a way it shouldn't, or introducing noise that it shouldn't;
- snakes.

 

[sprout21]

Trial but still error

Thanks everyone for all of the help...

I spent this evening testing all of the connections and equipment to try and locate where the noise is coming from.
Keeping the earphones on (attached to MBox), I can hear that the noise does seem to be mildly present even with Phantom Power and Protools off - just with the MBox connected to the laptop. It is very quiet but is amplified further when Phantom Power is turned on, and then record enabled/armed ready to start recording a track.
If I have the gain up to a certain point on the MBox I can keep the noise to a minimum, whereas as soon as I turn it up past that point (say 85 out of 100) it becomes very loud. Keeping it on the border of 85 keeps the noise low-ish, but between 85 & 100 is the realm where I need to creep into to have my speaking/raised speaking just below peak on the track volume. Therefore by keeping it where it is, the recordings sound ok but I am always having to amplify in post which brings me into noise removal territory

I agree with sjjohnston's comments about some level of noise being present anyway - just surely not the constant, weighty static that I am getting?? - which is a lot louder on the recordings than the only slight noise in the room when silent: my computer hum...
I just hate to accept that this is the best that I can get out of my equipment and that most of my time is lent to noise removing and intense volume tweaking in post - rather than just being able to simply lower or raise the volume of a clip before adding music/sfx etc

I know I am setting myself up for 'buy better equipment' comments, I am just sure that this there is a switch or setting or obvious thing I am overlooking/missing that is causing this - especially as it completely disappears say when I switch the function knob on the MBox from input to playback when nothing is playing.

I have switched USB's, swapped XLR's, tried both Mic Inputs, tried adding my Art MP Amp into the chain as suggested outputting via both XLR and 1/4 jack - all to no avail.

I would be happy with the noise if it was just a little quieter when I want max gain (without peaking).

Here is a example clip of the noise:View attachment 'Noise' Example Clip.mp3 Hope it works and hope someone might have any more suggestions as I am coming to the conclusion that it must be a slightly noisy mic

Thanks in advance for any additional advice and apologies for the long rant

 

[sprout21]

P.S. The noise clip is just me coughing/walking around the room etc and has been amplified

I fear people may say this is normal and then I will just have to accept that this level of noise is a formality, however if with the equipment I have got you think I should be getting more 'silence' and a true depiction of the room's ambient noise level - any help is muchly appreciated!

 

[tomanderson1991]

I have the C-2's which are the small Condensers and I haven't had any noise like that from them. As other people have said keep the main level down when I record from mine I never have it past the half way on my interface, as for your latest post regarding the 'amplified' part do you do that on all your recordings or just that one.

 

[RAMI]

Is it possible you're simply trying to record at too high a level? What level are you shooting for? Hopefully you're not trying to get "as close to 0db as possible". Beause if you are, then you're probably turning your pre-amp too high. You should go for an average level of well below -10db, with peaks hitting maybe at about -6db. Don't worry about volume when tracking.

 

[Shadow_7]

That seems almost normal to me if you have noisy mic(s). 20+dB noise A-weighted. Or if the A/C is running. Or there's a computer fan in play. You could probably lower that noise a bit with some room treatment. Otherwise normal to me on a < $500 a channel chain with high gain 40+dB in an untreated room. If there some air circulation going on (ceiling fan / vent), you might try a wind sock over the mic and see if that helps.

If you suspect the preamps, you can disconnect the mic and record it's noise, and use that as your noise profile for the noise removal phase. If you suspect the mics and have a stereo pair (that's matched) you can use both mics with elements close and gain matched, and phase reverse and mix them to get a noise floor and then mix it inverted with one of the original tracks to cancel out the noise. But the gain has to match, which might be hard to do. As in inverted cable + headphone preamp + manually tweaking until best no signal with the mono button on. But none of that really solves the noise issue.

It does seem a tad high, but not really I'm using a webcam high. If you have a microphone preamp in the mix you shouldn't need to be adding that much gain IMO. Relative to what you're describing anyway.

Behringer C3 mic
-------
BEHRINGER: C-3

Noise - 23dB (A weighted) (IEC 651)

 

[witzendoz]

I do a fair bit of voice recording in my studio, the speakers are often very soft as the project is usually of a meditation nature. My gear is very quiet but with the soft voice I still get some noise, it's around - 90 dB and on a band recording the amps and singer breathing is much louder.

Sometimes I have to resort to a noise reduction plugin, I have had good results with sony noise reduction and even better results with wave x-noise, both let you sample the noise so the plugin knows what it has to remove, then you have to spend time setting it up so it has no effect on the actual voice. I sometimes add a little room reverb (natural almost so you can't hear it) after so that any small effects will be covered up. Noise gates don't work as you hear them opening and closing.

Back to the set up, you need the mic gain up, if you get the first stage of the chain loud it should overcome noise further down the chain. The problem will be if the mic or pre has noise there is no cure for this.

Use a foam pop screen, I work on radio and we always use them, for spoken word it's the best way to go.

To fix the earth loop on the laptop/usb, you need a double insulated power supply for the laptop that does not have a mains earth.

Cheers
Alan.

 

[sjjohnston]

Keeping the earphones on (attached to MBox), I can hear that the noise does seem to be mildly present even with Phantom Power and Protools off - just with the MBox connected to the laptop.

That, presumably, is the noise added by the preamp in the MBox, all by itself.

It is very quiet but is amplified further when Phantom Power is turned on,

That's the noise from the mic itself, and its preamp.

as soon as I turn it up past that point (say 85 out of 100) it becomes very loud. Keeping it on the border of 85 keeps the noise low-ish

That's pretty normal. The more amplification in the preamp, the more it amplifies the noise from the mic, and the more noise it adds itself.

but between 85 & 100 is the realm where I need to creep into to have my speaking/raised speaking just below peak on the track volume.

That seems higher than I would ordinarily expect, but I don't know how much amplification the MBox has. Do you know what the gain is in decibels? I guess the MBox's dial isn't marked in decibels, but maybe you can figure it out from the manual or something.

With a condensor mic, you ordinarily shouldn't need anything close to the maximum gain of the typical mic preamp. In order to handle ribbon mics, distant room mics, etc., mic preamps typically have quite a bit more gain than you'd ordinarily need when using a close condensor mics, as the typical condensor mic puts out a pretty hot signal (by mic standards, anyway).

Which, I suppose suggest one or a combination of the following (just to cover the field):
- The model of mic you're using, in general, doesn't put out a very hot signal, just as a matter of its design.
- The particular mic you're using doesn't put out a very hot signal because something's wrong with it.
- The particular way you've got it hooked up reduces its signal. Not sure why this would be: I suppose inadequate phantom power voltage might do it. Apparently that's an issue with some mic preamps, as noted in some posts on this forum and elsewhere. How likely it is that the MBox in general (or maybe just your specific unit) might be suffering from that problem I don't know. Losing the balanced signal would knock off 6 dB, though it sounds like you've done enough expirementing with cables, etc. that that's unlikely to be the culprit.
- You need to talk louder or get closer to the mic.

Then again ....

Here is a example clip of the noise

Just as a rough first impression, that doesn't sound all that noisy to me. If you amplify enough to hear quiet background sounds (footsteps and stuff), the noise typically becomes pretty audible. Of course, the quiet background sounds are themselves noise (in both the common meaning of the word, and - assuming you're not recording sound effects for radio shows or something - its technical meaning as well). Your "signal" (voice talking) should presumably be a lot louder than both the environmental and the audio system noise.

Aside on other topics:

Removing this type of noise is fairly tricky. Just taking signals off two separate chains and inverting one won't do anything (it might mike it worse, actually), because what you're hearing isn't actually a predictable or regular periodic signal, but random variations. If you create a series of (truly) random numbers between -1 and +1, then add to it a separate and independently random series of numbers between -1 and +1, the sum will be a series of random numbers between -2 and +2. Changin the sign on all the values in one series first won't make a whit of difference.

Noise reduction software deals with this in different ways, some (apparently) more complicated, and some not all that complicated at all (like simply slapping on a low pass filter).

If your noise is in the range of -90 dB, it's much, much lower than what's typical, or what's considered acceptable for any ordinary recording. Among other things, consider that, if you produce and distribute a recording that has noise 90 dB below the signal:
- a listener who plays back the recording with a SPL of anything under 90 dB won't be able to hear your recording noise at all, and 85 dB or so is considered a "normal" listening level for music;
- the typical listener's playback system will have a much higher noise level than -90 dB;
- the typical listener is probably sitting in an environment where the background noise is much higher than -90 dB (more like -40 or -55 at the most, i.e. 45 dB SPL against 100 dB coming out of the speakers that are blasting).

Noise at -90 dB is pretty much the practical equivalent of no noise at all for audio recording. If you're building instrumentation for a particle collider or something, it might be a different matter.

 

[Shadow_7]

Sometimes adding that last little bit of gain digitally, versus running your preamps full bore can make a bit of difference in overall noise. For roughly equal results.