What level of background noise is acceptable in a recording?
Here is a question from a new Audio Masterclass student regarding their first recording assignment...
This is an interesting question. Professionally the answer is that the acceptable level of noise is none that is audible. You should be able to raise the listening level 6 dB above what is comfortable and hear hardly any noise at all. This is the standard that would be required, for example, for an audio book.
However, we accept that a lot of media is created that is capable of commercial exploitation, on YouTube for instance, where there is a significant noise level. The standard required is a little more subjective, but you should consider whether someone viewing a YouTube video would be irritated by the noise. This links to the content. It wouldn't matter if a 'funny cat' video had quite a lot of noise. If however a manufacturing company made their own widget demonstration video, then the irritation of the noise is competing for the viewer's attention against their potential interest in the product.
If you aspire to be a professional producer or engineer then you will be competing for work with people who are able to record with a completely silent background. For work such as voice over or foley effects, this is an absolutely essential requirement. For classical music recording it is very important, although you might consider http://en.wikipedia.org/wiki/Kingsway_Hall, specifically the section titled 'Recording at Kingsway Hall 1926-1984'.
Rock music is considerably more forgiving as the instruments are loud and vocals can be very close-miked. It is likely that the outgoing noise will be more of a problem than the incoming.
With electronic music, there is no problem at all with acoustic background noise, other than it may be a distraction for the engineer who needs to listen closely to the sound coming from the monitors.
When we listen to your work here at Audio Masterclass, we will be able to give you an indication of where you stand with regard to the above. However we would ask you to consider what lengths you would go to if this were the one piece of work that might secure your place, or your continuing career, in the audio industry. Recording at dead of night in between passing cars wouldn't be too far a step to take.