just to add a bit extra... it may be worth using a normalise process before compression. this is available in cool edit software. a normaliser raises all the levels present in the signal by the same amount and can double the percieved loudness of the sound. this is advisable before compression, as you get a maximum level output before compression. the problem with compression is that the higher levels are lowered, while the quieter levels are raised; this can give an unbalanced effect if not used lightly!!

tell me something. indeed, if you want to gain volume, you CAN apply a normalisation. But actually, the purpose of the normalisation is to gain loudness and the purpose of the compressor is to gain loudness. The only difference is that the compressor WILL work 100% of the time! A compressor is a professional mastering tool while a normalisation is a numeric trick to gain a little volume if (and only if) the higher levels are not at the higher limit (=if you already reduced volume before). So indeed, if you like loosing time, you can first apply a normalisation! You can also reduce volume by 50% then increase it by 50% if you like having fun!

the higher levels are lowered???? what are you talking about? so the purpose of the compression is to invert loudness?? No actually, indeed the lower levels are raised but thanks god the higher levels are still equal, and even a little higher I hope!

It's exactly like going from your L.A. to Mexico by scooter then take the plane to reach Rio De Janeiro! Anybody would say : "why didn't you go by plane FROM L.A.????"

sorry, obviuosly i didnt decribe the process accuratley!! a compressor DOES reduce the higher levels contained in a signal. hence the name 'compress'...to squash. imagine an orchestra that is at one arbitrary moment only playing with the flute section, then the whole orchestra plays. compressng this signal would make the flutes louder, and the full orchestra section quieter.
compressing is like taking an average.
normalisation will amplify all parts of a signal to a required level.
thankyou for your in depth analysis of my previous post!

now I perfectly agree with you

i use Goldwave to remove noise and DC offset from music i record from other sources...


it has a noise print filtering that is great for removing the base noise from a recording.... i've cleared up some CD's that have been "Professionally Recorded" here for myself and friends.... i just record a silent secion of a track or divice....such as the phono input inbetween tracks....then use that sound wave to remove the base noise from the final recording..... and there are options to corret the volume as well as EQ and DC offset........ plus you can run several functions on a batch of files to make your life easier.

and the shareware is full functional ........except that you can only do 150 commands before having to shut down the program and restart the software. it will function even after the 30 limit.....

I have foolishly used Normalisation in the past on all my tracks (newbie mastering to get levels of all tracks on cd relatively close - bad fix!). I dislike using Normalisation. :/