Horrible Signal-To-Noise, Is it my Mic?

  • Thread starter Thread starter kronosthekudu
  • Start date Start date
Good catch, man.
The specs he listed tie in with that model.

Read the amazon reviews here.
Just a load of people saying 'this mic needs phantom power' in capital letters (since the manufacturer doesn't mention it).
Although the article where you found that pic states the opposite.

One site had a user comment stating that there were two variants of this mic, (forgetting the 25 other Chinese names you'll find it under), one with a battery and one without.

Either way, the OP should be good with his phantom power.
 
I looked inside and mine doesn't have an internal battery. I didn't think to check inside of it.

20150207_082403.webp
 
I switched out my XLR - 1/8" cable, no change. And I checked the playback channels in audacity, no significant change between stereo, mono, left, or right.

I'm guessing the issue is either my mic, or my computer's audiocard. My plan is to try a USB audio interface and if that doesn't work, try a new mic.

Does that sound reasonable? Any suggestions? Y'all have been really helpful
 
I switched out my XLR - 1/8" cable, no change. And I checked the playback channels in audacity, no significant change between stereo, mono, left, or right.

Ah, that's a shame.
It was worth a shot.

I'm guessing the issue is either my mic, or my computer's audiocard. My plan is to try a USB audio interface and if that doesn't work, try a new mic.

Does that sound reasonable? Any suggestions? Y'all have been really helpful

100% reasonable.
Try the mic in another interface, or try another mic with your setup.
If possible try both setups with a new cable two....Anything you can do to eliminate each piece of the chain one by one.

Another thing you could try is plugging a pair of headphones straight into the Art Tube MP 1/4" output.
Ok, it's a line level output so it isn't ideal for headphones, but it'll tell you if a decent signal is coming out or not.
Noise will seem louder doing this ^ under normal circumstances, so keep that in mind. :)

There's a possibility that your computer input is a cheap mic preamp rather than a line input.
If that's the case then you're putting two preamps in line which is no good and could very well explain your issue.

I take it you're giving the ART unit power?
 
That's a good idea... unfortunately, I don't have any 1/4" headphones. Haha, yeah I'm giving the ART power.

I'll order the new gear and I'll post back my results!
 
That's a good idea... unfortunately, I don't have any 1/4" headphones. Haha, yeah I'm giving the ART power.

I'll order the new gear and I'll post back my results!

Oh wow. OK. Before you spend any money, have a think.
There's bound to be another device in your home that'll accept line level input via 1/4" or XLR for testing.

It's way far from ideal but even a guitar amp would do.

Any old headphones would be fine if you had a 3.5mm to 1/4 adapter. Do you have one of those?
What about another computer? Have you a laptop or a friend, with a computer, who'd let you do some testing?
Or even the current computer...Does it have more than one input socket?

What do your windows sound settings say? Does the sound control panel claim you have a mic input or line input?
Any options there like boosters or extra gain that you can turn off?

I'm just trying to exhaust possibilities incase you're wasting your money. :)
 
A couple of times it was mentioned about XLR balanced into an 1/8" stereo jack. I know this has caught me a couple of times that the balanced signal got pretty much canceled out when it was summed in the stereo jack. I wonder if you partially plug in the 1/8" plug so the tip only made connection to the ring contact in the jack thereby creating an unbalanced connection. Not sure this would work, but won't hurt to try. Hard to know how they may have wired the XLR to 1/8" cable.
Does the noise stay about the same if you turn off the phantom power to the mic? Or disconnect the mic?

Great suggestion. I was actually thinking along those lines and then I questioned if it makes sense or not.
If he's tried recording from left only or right only to test then that should be as good as pushing the connector in only so far that the tip meets the socket ring.

As you say, though, who knows how it's wired. It's definitely worth a try. :)
 
I'm a bit predisposed to action even if it is rash.

Anyways I checked different audio inputs. I found that I had a mic input rather than line input. With the line, the noise seems better but still pretty high.

Here are the waveforms: top is line-in, bottom is mic-in. Each have no audiocard boost. There is a few seconds of silence followed by an "ahhh" at speaking volume.
2015-02-07 09_11_26-Audacity.webp

As for 3.5mm to 1/4 adapter, alas, I don't, but I can ask around.
 
I'm a bit predisposed to action even if it is rash.

Anyways I checked different audio inputs. I found that I had a mic input rather than line input. With the line, the noise seems better but still pretty high.

Here are the waveforms: top is line-in, bottom is mic-in. Each have no audiocard boost. There is a few seconds of silence followed by an "ahhh" at speaking volume.
View attachment 91532

As for 3.5mm to 1/4 adapter, alas, I don't, but I can ask around.

Ok great. This is a start. :)

Can you post an mp3 clip of the line input recording, or even of both, please?
It's important to note whether it's a hiss, hum, buzz etc.
You can tell us, but hearing it would be preferable.

Does audacity show your line input as left and right? If so, which were you recording from.
Try left, then try right with the 1/8" half in as described above.
 
Just to get it clear, you are using an XLR-XLR cable to the preamp, then that goes to your computer, so the preamp supplies the power to the mic, and then your preamp supplies a line level signal to the computer via the 3.5mm mono (2 circuit connector). Just checking I have it right?

In all honesty, you need to borrow another mic and swap it to see if it works - this will identify the mic as the issue. It's VERY rare to have a faulty microphone - much more likely to be cable issues or settings on the PC.

People have mentioned a stereo ⅛" connector, but your computer, if it uses that connector is expecting a mono connector with the sleeve and ring shorted. The line in is a stereo connector, so if you have a line in and mic in on the computer, they're wired differently.
 
Here are the audio tracks:
Line in
Mic in

Rob - You have my setup correct. I'm not certain about the 3.5mm mono connector (how can I verify that?)
 
I also tested the resistance of my 3.5mm cable. Unfortunately my meter died before I could finish.
2015-02-07 09_34_22-Document1 - Word.webp
 
That's totally the wrong type of cable to go from mono balanced to stereo unbalanced. Pin 1 (and perhaps pin 3) should go to shield while pin 2 should go to tip and optionally ring. (Directed at the OP, not arcaxis.)

I'm reminded of what Brock Yates (I think) said, "You can't turn a pig into a racehorse, but you can build a hell of a fast pig."
 
No - ring and sleep to pin 1, which is shorted to 3, as in your diagram, with tip only to pin 2. If in the computer, the ring and sleeve are connected together, then the other version would effectively short it out.
 
No - ring and sleep to pin 1, which is shorted to 3, as in your diagram, with tip only to pin 2. If in the computer, the ring and sleeve are connected together, then the other version would effectively short it out.

I believe we have a stereo line input, in which case what Mark and I suggest should work.
 
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I'm guessing the cable's got nothing to do with it. Did you guys listen to that noise?

OP, if you record with the microphone unplugged but with phantom power on, do you get silence or heavy noise like that?
Trying another mic is probably the best bet. That's my guess.

Does audacity show your line input as left and right? If so, which were you recording from.

Answer this, please.
I doubt it's relevant now but should kill off the jack wiring questions.

Your testing proved the cable to be balanced to balanced. Regardless of what the input socket is I can't see the result being that amount of noise.
 
The noise is pretty bad with the mic out, especially with phantom power on.
No mic, phantom power
No mic, no phantom power

As for which channel, left or right, audacity selects for mono, I don't know. The setting I have been using as well as a stereo vs. mono recording can be seen below.
2015-02-07 12_33_16-Audacity.webp
 
The noise is pretty bad with the mic out, especially with phantom power on.
No mic, phantom power
No mic, no phantom power

As for which channel, left or right, audacity selects for mono, I don't know. The setting I have been using as well as a stereo vs. mono recording can be seen below.
View attachment 91539

Did you say there was a line input on your computer as well as the mic input?
Definitely stick to the line input for testing. Your screen dump shows the input is mic.
 
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