steve wrote:The recording level looks fine - the peaks in the loud part are at about -6 dB (0.5 on the linear scale) which is ideal. However, the tops of the peaks look flat, which indicates that the sound is being clipped/distorted before it gets to Audacity.
If you give full details of the equipment used and how it is all set up we may be able to suggest why that may be occurring.
Hmm, yea the peaks are a little flat. The loud part was a video being played on another laptop going through the mixer, more details below.
bgravato wrote:If you apply the amplify effect with the default options it will amplify the sound so that the new peak will be 0dB, this is the maximum you should have, above that you get distortion. Some people prefer to be a bit more conservative (like me) and amplify to a new peak slightly below 0dB (usually somewhere between -2dB and -0.3dB).
The levels in the first image look perfect, except for the flat tops which suggests clipping prior to audacity recording, as Steve suggested. Without knowing which equipment you used and how you have it connected we can't say how you can solve that.
The recording level on the second image look a bit too low.
If your recording has a lot of dynamics (some parts sounding quite loud and other parts sounding very quiet) and you want to narrow the volume differences between quiet and loud parts then you need to use dynamic compression. If you search the forum for dynamic compression you'll find a lot of threads about it.
Is this the dynamic compression you are talking about?
http://pdf23ds.net/software/dynamic-compressor/
The softer part in the second image is our pastor speaking, I guess I should raise his recording volume to match up closer to the video. I think the reason I have him down is because occasionally he accidentally blows on his wireless mic or saliva hits it or something and it makes a loud sound. It's hard to explain but I could easily find a clip of it if you wanted to hear.
waxcylinder wrote:Just to expand a bit on lturudic's advice:
1) It is generally thought best practice to apply DC offset correction as the first thing you do immediately after capture - apply no amplification at that stage. You onlt need to do this if your signal is carrrying some DC - you can see this when the waveform is off-centre from the zero line.
2) Normalization or Amplification is normall6y the last editing step after all other editing, i.e just prior to exporting your production audio files. Amplify and Normalize in Audacity both do similar, but subtly different things. Amplify works on both channels of a stereo signal equally whereas Normalize works on each of the two channels separately. So Normalize is good if you have unbalanced equipment in your recording chain - otherwise it is better to use Ampliffy so that you do not change or damage the stereo image.
3) the advice not to amplify/normalize up to odB is good - although this is the theoretical maximum peak loudness to avoid clippin some audio players do not like playing audio files with 0dB peaks. ltuuredic recommends -1dB, I am a bit more conservative peaking at -2.0db
(but even than my son complains that my recordings are too loud on his iPod - so-2.0 dB should be plenty loud enough 
).
WC
Maybe I should explain a little about what I am doing before I start describing the equipment so I don't come off as being rich, or being rich before starting all this, lol.
I volunteer at my church as the soundboard operator and do pretty much everything related to it. So this equipment is not mine except for the laptop I'm using to record but I can change anything I need/want to.
The mixer is a Yamaha MG32/14FX, I don't recall what the amps are but I figure that is unimportant for this, I can get the information next Sunday if it would be helpful though.
We have multiple mics and instruments on stage totaling 4 plus on average.
For videos we run the output (from headphone jack) from our laptop controlling the overhead into Channel 18 Input B on the mixer. (The loud part shown in the first image is from here)
We have a wireless mic for our pastor but I do not remember the make or model of it, I know I was unable to find a manual online for it from the manufacturer. It is on Channel 23 Input A on the mixer.(The softer part in the second image is from here)
Aux 1 and 2 are monitors on stage and I am using Aux 3 for recording, it is mono so I am mixing everything down to one channel and sending it to the recording laptop through it's microphone port configured as line in.
I plan to make a desktop with 4-6 sound cards configured with JACK and the
el cheapo mod and record each instrument and mic on a separate channel but I have to find the right parts first.
Well I think that's everything, if I forgot something or you want to know something else just say so and I will give whatever information I can.