Acceptable noise floor on mic?

[canada-paul]

Anyone know what an acceptable noise floor is on a mic setup?

I have an SM57 into a Behringer UB502 mixer, then into the line in on my SBLive. I'm getting about -60dB showing in CoolEdit with the mixer turned down all the way, or about -40dB when I'm not playing (there's lights on in the room, computer fan, monitor etc...).

Just wondering what the difference would be if I bought a real soundcard like a MidiMan. Would that -60 go down to say, -80? Is -40 to -60 an acceptable range for a guy recording on his computer? I'm going for 'hey, that sounds pretty good', rather than 'we're firing Bob Rock and hiring you'.

Thanks

 

[TexRoadkill]

-60 with the mixer volume down is pretty poor. Most decent gear should be able to give you at least -70 and good gear can go to -100 or better. With the mic open it is a bit different and it just depends on the level of your source. -40 would be fine for electric guitar but pretty bad for vocals and acoustic.

For a noise floor reference, cassette tape is usually around -60 -70. CD audio is around -80 - 90 and 24bit pro recorders are capable of -140. It's a good idea to have a system that is as quiet as your final output which nowadays is usually CD. Since the Delta's and other good cards can record in 24bit that lowers your recording format noise floor automatically (but not the mixer).

The bottom line is do you notice it in the final mix? If you are trying to do quiet, detailed acoustic stuff then you will have problems. If your playing loud rock or pop then you should be fine.

 

[canada-paul]

Thanks for the tip. I'll assume that most of the problem is in the soundcard for now. But I am doing mostly louder type stuff, so I can probably live with it for the time being. I just wanted to know what the ballpark figure was.

I don't know how good these Behringer mixers are. I see them mentioned all the time, and it was a good price new, so I got it. I'll assume that the difference between it and a Mackie (or whatever is a step up) is marginal compared to the difference I'd see with a better sound card.

 

[Thom IV]

I’m running an AKG C4000B, AKG C3000, Shure Beta87A, or a Shure SM57 (not to mention the numerous no name brand mikes that I occasionally use when I need extras) through a Mackie CFX12 mixer into a Delta44.

I noticed a huge difference in my noise floor when I switched from my SB compatible built into my mobo to the Delta44.

There was also a significant difference when I started using the condenser microphones...MUCH quieter...

IMHO, it’s a matter of your whole setup...you’ll get as much noise from the weakest link in your setup.

Bottom line--I think you would notice a significant difference if you were using a ‘professional’ soundcard, compared to your SBlive.

That being said, I think Tex hit the nail on the head when he made the point regarding how the noise floor was in the final mix, as well as the fact that it depends to a large extent on the type of music you’re recording.

Good luck.
Tom