Noise problem with recommended audio setup

Drigor · Post by **Drigor** » January 8th, 2007, 8:41 am

I bought the Shure Beta 58A microphone togehter with the preamp MobilePre USB from M-Audio and are surprised at the high noise level.

The distance mouth - microphone is about 8 in. All gains are set to max. Even if I talk loudly, I hardly reach the maximum level (0 dB).

Can anyone tell me if this is really okay?

http://home.arcor.de/t2c/testrecording.wav (796 KB)

I expected a much lower noise level.

Any suggestions are highly welcome.

Regards,
Igor

Post by **hugh** » January 8th, 2007, 9:26 am

hmm it does sound a little bit hissy, but other than that the sound quality is v good.

Drigor · Post by **Drigor** » January 8th, 2007, 9:30 am

Do you mean hissy, like having a hissy fit? (Actually, that was one of my calmer performances ...)

Anyway, I mean the noise level. It is at about -51 dB. Isn't it extremely high?

Regards,
Igor

jimmowatt · Post by **jimmowatt** » January 8th, 2007, 9:36 am

It's a perfectly fine recording but I suspect your gains shouldn't be set to max. Is the pre-amp working OK?
Have you got a link to the site for this pre-amp?
What you need to aim for is a large difference between foreground and background sound so with the gains up it'll be picking up everything. I'd get a little closer to the mic and turn the gain down. If you find yourself popping ('plosives) then make or buy pop filter or practise saying p without the expellation of air or turn your head slightly when saying p.

It's actually a nice sound but it'd be even nicer if that background hiss could be edged out.

Kind regards

Jim

Post by **hugh** » January 8th, 2007, 10:37 am

hissy = has a background hiss

Drigor · Post by **Drigor** » January 8th, 2007, 11:35 am

hugh wrote:hissy = has a background hiss

I know, I wanted to make a bit of fun.

Jim wrote:It's actually a nice sound but it'd be even nicer if that background hiss could be edged out.

It is no background hiss, it is the noise from the preamp. Even if I unplug the microphone, this noise remains.

The preamp is the Mobilepre USB from M-Audio. The M-Audio engineer says, a dynamic micorphone is not the right type to connect to this preamp. The reason is, this preamp has a maximum gain of +40 dB, whereas one needs probably at least +60 dB.

I know that Shure actually recommends this preamp for their dynamic microphones (SM58, Beta 58A, SM7B). But M-Audio says: no way, unless you "bite into the microphone."

The application engineer from Shure Germany says the same thing: if the preamp has no more than +40dB gain there should be a condenser microphone connected.

Frankly, I am confused. I had the same noise level (appr. -50 dB) with my totally cheap microphone from the supermarket and my Soundblaster Audigy.

Should I return all the stuff or should I have another shot at a condenser microphone?

Oh well.

Regards,
Igor

Please listen for yourself

http://home.arcor.de/t2c/Comparison.mp3 (146 kB)

Drigor · Post by **Drigor** » January 9th, 2007, 2:08 pm

So, this is the last attempt with the Shure Beta 58A. I unplugged the M-Audio MobilePre USB because, after reading on the Internet, I found out that it is the reason for the unpleasant noise.

Please listen for yourself, this is the Beta 58A in "biting distance" to the mouth, plugged in my Soundblaster Audigy without preamp.

http://home.arcor.de/t2c/Igor_BC.mp3 (1.553 KB)

Uh, and don't worry, if I read for Librivox. it'll be in German.

Regards,
Igor

Starlite · Post by **Starlite** » January 9th, 2007, 2:10 pm

What kind of file is that? I can't open it.

kristin · Post by **kristin** » January 9th, 2007, 2:13 pm

I think it sounds fine. Why won't you be reading in English? You do it very well.

Drigor · Post by **Drigor** » January 9th, 2007, 2:15 pm

Starlite wrote:What kind of file is that? I can't open it.

Hm, it's an mp3-file. The only technical property, worth mentioning, is that it is VBR-encoded.

Did something go wrong during upload?

Could someone please verify that the file is corrupt. I hesitate a bit to download it again because currently I am connected via a modem.

Regards,
Igor

kristin · Post by **kristin** » January 9th, 2007, 2:16 pm

It opened for me just fine in windows media player.

EDIT: I just looked at it and it is in an odd bitrate 192kbps. Could that have something to do with it?

Starlite · Post by **Starlite** » January 9th, 2007, 2:35 pm

HEe hee, I think it wasn't finished uploading when I clicked it. Looks ok now.

Starlite · Post by **Starlite** » January 9th, 2007, 2:37 pm

Wow, it sound great. Your English is very good. Aww come on... record in English too. Don'deprive us non German speakers the pleasure of listening to your voice.

Drigor · Post by **Drigor** » January 10th, 2007, 10:05 am

Starlite wrote:Wow, it sound great. Your English is very good. Aww come on... record in English too. Don'deprive us non German speakers the pleasure of listening to your voice.

Thank you.

But technically I am not entirely pleased. I mean, the voice sounds not as pleasant as I would like to hear my own voice.

The midfrequency range seems to be overemphasized. As often with voices, it could be possible that it gives the voice an individual touch and maybe, it is even advantageous for listening in cars.

Anyway, the good thing with the Beta microphone is, it does not produce pops, no matter how close one gets.

Regards,
Igor

Le Marteau · Post by **Le Marteau** » January 12th, 2007, 10:48 am

I had (have) a similar issue with my mic and pre-amp combination as well (M-Audio, BTW). I can never get the output to approach 0db. And if I turn up the gain too much on my preamp, it will end up clipping well before 0db. Plus, if the gain is maxed, it adds hiss.

The solution for me was to back off on the preamp gain, and accept that the output will be low. Then, in Audacity, after recording, I can normalize it so that the peaks approach 0db. I end up with silence being less than -50db and ususall it does not meter at all, which makes me very happy.

The cause of your hiss might be that you have your outputs maxed. Try putting that at 90-95% and see if that helps.