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If any of you can help, I'd greatly appreciate it.

I'm recording audio books and went out and bought some pretty decent equipment to get going.

Mic: PR40 on a boom w/ the spider holder thing
High end cables
Byerdynamic DT 770 head set
Alesis Multimixer 8 USB, Mixer

I think my mixer sucks, but I'm not sure. When I plug my headphones into the mixer even WITHOUT any mic or other input, I hear a considerable amount of static or white noise. Then when I plug my mic in, it gets worse. Then when I actually start recording via the USB to both my laptop and desktop, I get a terrible hum or electric buzz that gets picked up on the recording.

It's driving me crazy! I've tried grounding the mixer to my computer, but without any noticeable results.

Am I expecting too much? I'd like to plug the headphones without a mic and hear nothing. Then, when plugging in the mic, hear only room noise without additional static/white noise.

I'm new to this, so maybe this is normal?

BTW, it's not ambient room noise I'm picking up, it's definitely coming from an electronic source.

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Comments

pr0gr4m Sun, 06/17/2007 - 04:09

Buzz is common, but can be prevented.

From your description however, you may have problems with two types of noise problems, regular everyday equipment noise and ground related noise.

First address the ground noise. If you can, plug everything into the same circuit. Houses are wired in all sorts of magical ways and using two outlets in one room doesn't necessarily mean they are both on the same circuit. Using outlets that aren't on the same circuit can introduce grounding problems which means noise or buzz or 60-cycle hum or whatever the kids are calling it these days.

When I encounter these sorts of problems, a quick thing I will do to test for ground problems is add a ground lift to the plug of one of the devices. If adding that gets rid of the hum, then there is a grounding problem. I don't recommend running your equipment without a ground lift all the time but in a pinch they do come in handy. If you do have a grounding problem, the only thing I know to do is plug everything into the same circuit, use power conditioners/noise suppressors or have an electrician look at the wiring. I'm no expert on this sort of thing so maybe someone else will have some more info on what to do.

Next address the equipment noise issue. Start with just the mixer. Plug it in to your computer and start the software you are using for recording. On the mixer turn the GAIN, LEVEL, AUX sends(pre & post), AUX EFFECTS MAIN MIX and HDPH knobs all the way down. Next set the EQ knobs at zero (in the middle). Make sure that none of the effects in the mixer are on.
You shouldn't hear anything in the headphones or on the computer. If you do, take the thing back and get something else.

The gain is probably the biggest source of noise on the mixer. You can test that by turning the main mix up 25%, turning the level up for channel 1 25% and plugging the mic in to that channel. At this point you still should be relatively noise free. Test the mic. If you can't hear anything or it's very quiet add a little bit of gain, and/or increase the channel/main level. What you need to do is find a comfortable mix of gain and level so that you get a loud enough signal from the microphone with very little noise.

Good luck.

BobRogers Sun, 06/17/2007 - 04:17

No way for me to tell if this is normal without more info. Every electronic component has a "noise floor." If you turn the headphone amp up enough you will hear it. Better components will have lower floor - a higher ratio between signal and noise.

Plug the mic in, adjust the gain so that your voice tests are at nominal 0 dB level, and then adjust your headphone output so that the voice is at a comfortable level. Is the noise still noticeable?

Boswell Sun, 06/17/2007 - 04:40

What happens if you switch off the computers, disconnect the USB cable from the mixer and use the headphones on the mixer monitor jack? If you get the static noise then with the gains turned down, you have a fault in the mixer and you should get it repaired under warranty. If it's OK, plug a mic in and raise the level. See if that's OK.

I would bet that your troubles don't start until you plug the USB cable in. It sounds as though interference from the computer and USB is getting into the mixer. This may still be a mixer problem, or it could be to do with how well grounded the whole system is. Try recording to the laptop running off its internal battery and see if that is any better.

anonymous Sun, 06/17/2007 - 09:44

BobRogers wrote: No way for me to tell if this is normal without more info. Every electronic component has a "noise floor." If you turn the headphone amp up enough you will hear it. Better components will have lower floor - a higher ratio between signal and noise.

Plug the mic in, adjust the gain so that your voice tests are at nominal 0 dB level, and then adjust your headphone output so that the voice is at a comfortable level. Is the noise still noticeable?

Sorry that I have to ask this, but I don't understand what the "voice tests are at nominal 0 dB level" really means. When I'm recording and my meter's running, if I'm not talking or making noise, my meter is reading -50 (don't know if this is dB or not)....

I have adjusted the gain as others have recommended and I do loose some of the buzz, but I feel I'm loosing a proportionate amount of volume. That is, everything gets quieter and hardly registers on my recording program. Then I have to amplify everything up, but in so doing, I boost up that annoying hum, and I'm back to square one.

I have also run some of the noise filters on the recording, but to get to the point of getting rid of the hum, my recording starts to sound very "digital" (kind'a like a 56kbs streaming audio sound from the internet). And I know that this isn't the proper solution anyway. I want to start with a clean, virtually-noise free recording.

anonymous Sun, 06/17/2007 - 10:01

Boswell wrote: What happens if you switch off the computers, disconnect the USB cable from the mixer and use the headphones on the mixer monitor jack? If you get the static noise then with the gains turned down, you have a fault in the mixer and you should get it repaired under warranty. If it's OK, plug a mic in and raise the level. See if that's OK.

I would bet that your troubles don't start until you plug the USB cable in. It sounds as though interference from the computer and USB is getting into the mixer. This may still be a mixer problem, or it could be to do with how well grounded the whole system is. Try recording to the laptop running off its internal battery and see if that is any better.

Thanks for the suggestions, and I have implemented all of the above. Here's the results:

1. Disconnected USB from mixer. Disconnected Mic from mixer. Only headset plugged into the "phones" output. All gains and volumes down. RESULT: With "main mix" and "control Room" cranked all the way up, I can hear slight white noise... I assume this IS normal since it isn't annoyingly bad and kind'a just has that "electronic devise sound"

2. Plugged in a mic. Turned up level 10% and gain 10%. RESULT: The white noise from above is amplified proportionally with the increase in volume.

I might interject this comment here that when I have the "2 TK tO MIX" button off the sound is much better than with the button on. With it on, the white noise is just about doubled WITHOUT an increase in overall volume.

3. Plugged USB into mixer. RESULT: No difference in white noise or anything else.

4. Ran program from laptop on battery. RESULT: No difference. I get the same noise from my laptop on battery or on wall power. Same noise, in fact, when on a desktop.

When I especially notice the noise when I press the record button on the CPU AND have the "2 TK TO MIX" button on. Then things get really buzzy. If the button IS NOT on while recording and I just do a quite record (that is, no noise being made by me), the visual of the recording isn't a nice single pixel line. It turns into a 3-4 pixel line, and when I zoom in on it, it seems to be pretty constant... not changing in size much.

anonymous Sun, 06/17/2007 - 10:13

pr0gr4m wrote: Buzz is common, but can be prevented.

From your description however, you may have problems with two types of noise problems, regular everyday equipment noise and ground related noise.

First address the ground noise. If you can, plug everything into the same circuit. Houses are wired in all sorts of magical ways and using two outlets in one room doesn't necessarily mean they are both on the same circuit. Using outlets that aren't on the same circuit can introduce grounding problems which means noise or buzz or 60-cycle hum or whatever the kids are calling it these days.

When I encounter these sorts of problems, a quick thing I will do to test for ground problems is add a ground lift to the plug of one of the devices. If adding that gets rid of the hum, then there is a grounding problem. I don't recommend running your equipment without a ground lift all the time but in a pinch they do come in handy. If you do have a grounding problem, the only thing I know to do is plug everything into the same circuit, use power conditioners/noise suppressors or have an electrician look at the wiring. I'm no expert on this sort of thing so maybe someone else will have some more info on what to do.

Next address the equipment noise issue. Start with just the mixer. Plug it in to your computer and start the software you are using for recording. On the mixer turn the GAIN, LEVEL, AUX sends(pre & post), AUX EFFECTS MAIN MIX and HDPH knobs all the way down. Next set the EQ knobs at zero (in the middle). Make sure that none of the effects in the mixer are on.
You shouldn't hear anything in the headphones or on the computer. If you do, take the thing back and get something else.

The gain is probably the biggest source of noise on the mixer. You can test that by turning the main mix up 25%, turning the level up for channel 1 25% and plugging the mic in to that channel. At this point you still should be relatively noise free. Test the mic. If you can't hear anything or it's very quiet add a little bit of gain, and/or increase the channel/main level. What you need to do is find a comfortable mix of gain and level so that you get a loud enough signal from the microphone with very little noise.

Good luck.

Thank you very much for your detailed reply back.

Firstly, I have everything on the same circuit. Secondly, when I turn all my levels and gains down and the main mix and headphone volume down, I hear absolutely nothing.

But, while continuing to have all the levels/gains down, I turn up the main mix and headphone volume up, I can start to hear what I would call white noise..... just a slight static. If I crank them to 100%, the noise is certainly there. It's not huge, but it's there nonetheless.

Regardless if the mixer is connected to the computer or not, when I turn my mic level up, the very same static/white noise seems to be amplified. Then after pushing the "record" button, the SAME static noise is again louder/amplified. Then with the 2 TK TO MIX button on, the static gets louder and slightly "buzzier."

Thanks again for all you guys' help!

anonymous Sun, 06/17/2007 - 11:01

[quote="Anthem
Thank you very much for your detailed reply back.

Firstly, I have everything on the same circuit. Secondly, when I turn all my levels and gains down and the main mix and headphone volume down, I hear absolutely nothing.

But, while continuing to have all the levels/gains down, I turn up the main mix and headphone volume up, I can start to hear what I would call white noise..... just a slight static. If I crank them to 100%, the noise is certainly there. It's not huge, but it's there nonetheless.

Regardless if the mixer is connected to the computer or not, when I turn my mic level up, the very same static/white noise seems to be amplified. Then after pushing the "record" button, the SAME static noise is again louder/amplified. Then with the 2 TK TO MIX button on, the static gets louder and slightly buzzier.

Thanks again for all you guys' help!

After reading through this several times it seems as though you have a noisey mixer- something that I bet everyone has to work with at some point. The noise you hear with just the main mix and headphone turned all the way up is probably normal for that unit. The noise you hear"amplified" from the mic preamp circuitry is the sum of the noise from your main mix circuitry and your mic preamp and will increase proportionately for every channel you mix in. The headphone amp will add its own noise if it's cranked all the way but should not end up on your recording.
To ensure your recording sounds as noise free as possible, try keeping the main mix no higher than it's mid range volume and any mic preamp trims rolled down a few db and the mic gains down to the minimum required for a decent level at your main mix output ( the analog output to an amplified speaker would be a good way to test if there something wrong with the mixer circuitry ). If it sounds good on the analog out to an amplified speaker you probably have a noisey headphone amp or other issues with the usb circuit. Keeping all gains at the minimum required levels may be your best bet unless of course you just have a defective unit. Then it's time to try another.

Good luck
gb

RemyRAD Mon, 06/18/2007 - 02:02

LOL! One might think that recording audio books should be simple, since we are talking about a single person, with a single microphone, should be an easy thing. Right? It's not. In fact, spoken word is particularly difficult to do well. Even if you don't have to deal with the buzz. Your mixer isn't crap, it's just mediocre, which is fine for your purposes.

Buzz, is usually indicative of grounding problems or bad cables. High-voltage sources such as television sets and microwave ovens can be a source of problems along with computers and cellular phones.

The dynamics of the speaking human voice, actually doesn't sound good by itself. Once you figure out that you need some dynamic range compression and/or limiting, suddenly, you'll realize that your acoustic space doesn't sound good. Suddenly, you'll be hearing all of this other background crap and lousy acoustics. What to do? 2 words. DOWNWARD EXPANSION. NOT GATING! GOT THAT? Well, that's 6 words total. Downward expansion is similar to gating except that a gate is either on or off. That makes your voice sound even worse with the background noise switching on and off. What you need to do is merely add some downward expansion or "gating" that stops at between 6 to 15 DB and does so smoothly. The trick is to adjust the threshold so that the downward expansion only starts to happen at the quietest passage, during your breath and should generally not be any more than the amount of compression/limiting you are using. If you can accomplish this feat, they'll certainly want you to do more talking books for them because you're talking books, will sound the best.

Talking to myself
Ms. Remy Ann David

anonymous Mon, 06/18/2007 - 10:01

RemyRAD wrote:
The dynamics of the speaking human voice, actually doesn't sound good by itself. Once you figure out that you need some dynamic range compression and/or limiting, suddenly, you'll realize that your acoustic space doesn't sound good. Suddenly, you'll be hearing all of this other background crap and lousy acoustics. What to do? 2 words. DOWNWARD EXPANSION. NOT GATING! GOT THAT? Well, that's 6 words total. Downward expansion is similar to gating except that a gate is either on or off. That makes your voice sound even worse with the background noise switching on and off. What you need to do is merely add some downward expansion or "gating" that stops at between 6 to 15 DB and does so smoothly. The trick is to adjust the threshold so that the downward expansion only starts to happen at the quietest passage, during your breath and should generally not be any more than the amount of compression/limiting you are using. If you can accomplish this feat, they'll certainly want you to do more talking books for them because you're talking books, will sound the best.

That's what you said. This is what I heard:

RemyRAD wrote:
الصين العلاقات التونسية الصينية بأنها ممتازة وقال في حوار أجرته معه /شبكة الصين/ إن البلدين ظلا سياسياً يعملان منذ سنوات بتنسيق وتشاور تام لأنهما يشتركان في مواقفهما من أمهات القضايا الدولية والاقليمية والتي يشهدها العالم ي
الصين العلاقات التونسية الصينية بأنها ممتازة وقال في حوار أجرته معه /شبكة الصين/ إن البلدين ظلا سياسياً يعلان منذ سنوات بتنسيق وتشاور تام لأنهما يشتركان في مواقفهما من أمهات القضايا الدولية والاقليمية والتي يشهدها العالم اليوم.

So... Umm... Thanks! :) I, unfortunately have no clue what that all means.... SO SORRY, but I am VERRRY interested! I so wish I knew what all that means....

How do I obtain this "downward expansion" and all that other wonderful stuff? Can I get all that with the DBX 286 that you recommended in another post? Should I just dump my mixer and use a DBX286 and my PR40 mic? Is that going to help me?!?

RemyRAD Mon, 06/18/2007 - 21:04

I am a Gary Larson fan, blah blah blah Fido. And what the cat hears....... (Blank). Sorry that was overly confusing for you.

Yes, I don't think you should bother using your mixer.

There is a substantial difference between the 386 and the 286 from DBX. And more than twice the price difference. But then you are getting 2 channels of tube preamp with the 386 and only a single channel with the 286. The digital outputs on the 386, don't do you much good, unless you have a compatible digital interface for your computer, which you don't have.

I still stand on my recommendation of the 286, for $200 plus the Edirol (by Roland) line level, USB audio interface, for $80. Everything you need for your spoken word recording is in the 286. No need for expensive software. Shareware such as Audacity would be fine, since you would really only need to record and edit your voice and not have to worry about trying to achieve analog style dynamics processing with software. That old-fashioned analog thang that the 286 offers can make your life easier. That software stuff can become more confusing, frustrating and problematic I think for a person with your need to efficiently produce your talking book series, with excellent and consistent results with a minimum of postproduction, the 286 has your name on it. That downward expansion stuff is done very nicely by the 286, which tightens up the sound and eliminates background noise while making bad acoustic spaces less noticeable. The "De-Esser" keeps your "Esses" (S's sounds) from splattering and distorting your recording. The compressor/limiter will give your voice a beautiful smooth listenable quality. The high pass filter will illuminate rumble in the room and the equalizer can add some additional sparkle, if needed. I actually installed one of those devices for John McLaughlin (the political talkshow host not the guitarist) in his office so they could painlessly cut his vocal track itro's for his television shows without any mess or fuss. It's been in continuous service for over eight years now.

If I can be of any further help....
Ms. Remy Ann David