S8-N is right that a low-mid heavy sound will tend to have a fuller look.
doc is correct that a fuller look means that the wave form has more samples closer to maximum. And is correct that the upper part is "push" and the lower is "pull, although, these are not technically correct terms, as doc well knows. He was just keeping it simple.
The upper and lower parts of the wave form are the + and - polarity of the sound. All sound waves have a + and - value that make one cycle. If you start at the center (no value) the wave form starts by going up (possitive value, how high means amplitude, or volume) then crosses back over 0, then goes down (negative value, how low means amplitude). So, the process of going up, then down once is a cycle, or hertz, or frequency. You need to see several in a row to get a feel for the actual frequency, because it means nothing unless you have several in a row. 1 cycle happens to fast for the ear to detect it. So, just one hi hat hit would have several of these up and down movements. It is the accumilation of all of them that makes it sound like a hi hat hit to our ears. Anyway, frequency is how many of these up and downs happen per second. A hi hat hit would be somewhere around 2-12KHz, or 2000-12000 or these up and down cycles per second. Even though a hi hat hit doesn't last a second, it is still a frequency of 2-12KHz per second because if the hit WAS a second long, that is how many up and down movements it would make.
Wave forms and how the correlate to sound? Well, like all the others are suggesting, don't worry too much about it.
The wave form being symetrical? Possibly something to worry about. This could suggest a DC offset somewhere in your recording chain. The most likely culprit is your soundcard. Cheaper ones tend to have pretty bad DC Offset problems. My old yucky Yamaha soundcard suffered from it pretty bad. DC Offset WILL cause distotion to a certain degree. The more of it there is, the more distortion you have. If you soundcard has a option to recalibrate the DC Offset of the converters, use it often. I know that higher quality digital recorders reset DC Offset when the tape is not moving. So the offset is constantly adjusted and updated. Soundcards to not enjoy this feature. But
my Lynx One sound card has a converter calibration function that I seldomly need to use. But once a week I use it just in case...
But the offset can also be from other things going into your soundcard. A preamp, mixer board output, mixer line in OP amp, compressors, etc.... Quality components means less offset. I have mp3's that have some very severe DC Offset problems, as well as .wav files from others with the same. Cheap units will suffer from it. Cheap tube devices can be particualily bad too, as tubes deal a lot of DC Offset. Usually means a tube going bad, or is not biased correctly.
You will notice that big boy recordings tend to have a fuller wave form when viewed in an editor. You will also notice that it sounds a heck of a lot better too...
So, there is a correlation between fat looking wave forms and your audio. But, few, if any of us are dealing with the quality of equipment that the big boys have, so expectations need to be lowered.
The reason that the wave form looks different between your two mics suggest the qualitive difference between the two. The Rodes is picking up a lot more of the infomation accurately, thus, fuller wave form.
The day you get your first really killer sounding mix (I mean the one that REALLY sound close to a big boy recording) you will see a very full looking wave form in your editor too.
Ed
[This message has been edited by sonusman (edited 05-23-2000).]
