How do I get the right volume levels?

Special thanks to Doug Kaye of IT Conversations and Paul Figgiani of The Point Podcast and IT Conversations. Although I don’t know them personally, I would not understand audio levels at all without the guidance they have provided to the podcast community.
Ironically, the levels in this podcast are just a touch too loud as I peak in some spots. It’s not too bad though and I don’t have time to re-record.

Notice how some podcasts are too quiet while others have a nice big sound while others still sound too loud and distorted in spots (especially poppig ps)?
Getting the levels right is tricky because on one hand you want to have a nice big loud sound but if you get too loud it distorts or peaks above 0 db.
You need a tool for measuring the average levels or RMS levels - root mean square.
Higher end editors have RMS Normalize - Peak Pro, Wave Editor (mac, on the PC - Soundforge, Audition

Punch in -17.5 db and your done
The application boosts levels that are too soft and quites those that are too loud
These apps are expensive star at $299 up to $599 (Peak Pro) - get academic discount

I don’t have $300 for software - what do I do? 2 free Mac prgrams - one can also work on Windows
RMS buddy is one free tool available as a AU plugin on OSX and a VST plugin in Windows - works in Garage Band, Soundtrack Pro

AudioLeak (Mac) is standalone app that can measure RMS levels of a whole audio file in a few secondes - even of it’s a 60 minute audio
How to control this?

1. Manually with mic technique - I turn input levels up 80% of the way, move in close (approx. 8 inches from the mic of to the left side a bit) and speak in a steady voice. If you speak loudly in some spots move your head in the other direction a bit.
Limiter - software or hardware. A limiter cuts the volume levels of at a set point like -1db or -0.5db. It doesn’t allow a recording to get louder than this. I use this in recording with garaqge band. Works well.
Compressor similar to a Limiter but more gradual. Starts limiting lelvels as they get to a certain threshold - say -12db. This alloes you to boost the average levels without getting too loud. Can be tricky in pratice.
Record at lower levels and boost in post using a limiter to assure you don’t get too loud (clip).

Even if you take these measures - you may find it’s not right in fact how do you know the levels are right or if you just have your headphone volume too loud or roo soft.
You want to shoot for RMS levles of about -15 to -17 db
How to boost

Fundamentals of Digital Audio Podcast