Freesound Forums

Q1: What is the purpose of the compressor (Audacity)?

Q2: What does SC4 do?

Q3: What are the theories behind "Harmonic generator*", "Hilbert Transformer*", and "Wave shaper*"?

Q4: Has anyone else been having trouble with Nyquist gen-plugins? My Buzz generator doesn't work at all ("Nyquist returned the value: ##.###", and my Klusterbass, harmonic noise, and Risset drum generators sometimes cause audacity to freeze up.

Q5: A lot of my delay plugins refuse to work (bbdelay). Some work, but don't do anything (allpass delay(s)*, fractionaly addressed delay line*, et cetera...)

Thanks for any feedback and help! :?

* = I got these effects from a LADSPA pack of 90 different effects. Found on the audacity website.

I will just answer the first question,

In some words, compression is just make harder the volume
of the audio without clipping(distortions) or without distort it but,
there is limits to that ...

the best is to try it :mrgreen: ...

I have used it a few times but when I hear people talking about how "great" compression is I think: "What's so special about that?" :?

This is an effect like anothers,
I never find this special but,
this is just very usefull in Mastering ...

And this is now used everywhere :evil: ,
just hear pop/rap/rock/metal commercial music and video and audio publicity to realize that...

I never use the plugin effect "Harmonic generator" but,
I think that I know what it"s done

For instance you want a frequency of 400Hz but not directly,
Just mix two tone of 600Hz and 1000Hz,
because 1000 - 600 = 400,
but that generate an second tone of 1600Hz,
because 1000 + 600 = 1600,
but remember that on the output the four tone are present,
for this instance: 400Hz + 600Hz + 1000Hz + 1600Hz

just use low-pass filter between 1000Hz and 1600 Hz to eliminate the 1600Hz...

It"s just stupid mathematics :mrgreen: ...

compression is good. it allows you to pump up the signal to be louder and thicker (phatter whatever). if you know how to use it properly you will see the benefits of it. more compression will give you a phatter sound. so you can pump the volume up louder without distortion.

Hilbert transform: http://en.wikipedia.org/wiki/Hilbert_transform

Again that"s stupid mathematic...

Whoever types up all those equations must be absolute losers... I suppose it means something to somebody though...

If you can just show an print-screen/preview/picture
of the windows panel of the effect "Hilbert transform" :wink:
that can help me to say what suppose to do
because I"m too stupid to go and download the pack ...

if you can try it and show preview before/after :twisted: ...

That's just the thing! You see, there is no window that pops up! It has no dialog box O_O! And the sound sounds the same... But if I press Ctrl+R over and over for a few minutes, the entire sound moves slowly to the right, cutting it off as it goes! It's pointless!

...I see on the net that audio programmers use "Hilbert Transform"
in many case for make phase +90deg. phase shift or/and make delay
on an specific frequency or on the most hard frequency on in the sound,
not all the sound just the the specific freq and mix in the sound...

so if you can check and say what delay in samples and in sec. the fx do

...check with the plot spectrum is there is an difference and what is the higher freq?

Compression can be used for a few different purposes. Most of the time people use it to make the quiter parts of something louder without turning the already loud parts any higher. I have never found a true transparent Compressor that did not modify the sound or create distortion but you can try alot out and hear for yourself.

I hardly use em, only on drums when the drums' volume is a bit low but the large peaks of the wave are already going over 0dB I'll use a bit of compression to take off some of the top peaks so I can push the volume of the drums louder.

It is true that alot of the music you hear today is highly compressed, and a good example I that I read once of sound, in this day and age, not being compressed is sound from the cinema. the dynamic ranges in movies are a good example of uncompressed sound.

yewbic
It is true that alot of the music you hear today is highly compressed, and a good example I that I read once of sound, in this day and age, not being compressed is sound from the cinema. the dynamic ranges in movies are a good example of uncompressed sound.

I'm not sure that's entirely true. If you think that there's no compression on a movie soundtrack, you're fooling yourself. Mixing a movie soundscape from scratch is difficult, there's a lot of sound that you have to consider. A major motion picture can have well over 120 tracks to mix, and without a little compression in the right spots, it wouldn't sound nearly as good as it does. But, as was mentioned, you have to know how to use it.

tweeterdj

yewbic
It is true that alot of the music you hear today is highly compressed, and a good example I that I read once of sound, in this day and age, not being compressed is sound from the cinema. the dynamic ranges in movies are a good example of uncompressed sound.

I'm not sure that's entirely true. If you think that there's no compression on a movie soundtrack, you're fooling yourself. Mixing a movie soundscape from scratch is difficult, there's a lot of sound that you have to consider. A major motion picture can have well over 120 tracks to mix, and without a little compression in the right spots, it wouldn't sound nearly as good as it does. But, as was mentioned, you have to know how to use it.

yeah i shouldnt have said "uncompressed sound" just an example of the differences between squashed square waves and very large dynamic ranges of some motion pictures. or i suppose you can look at classical/orchestral music as well.

flowers: this might be chalked up to Audacity itself. I've certainly found the VST support to be lacking, and most VST plugins I tried with it were unusable.

Not sure about LADSPA, but the stuff distributed with audacity (filters/effects, tone, silence, and noise generators) work fine for me on windows and mac.

If you want to use VST you might have better luck with a purpose-built VST host program. (Search forums, I know whe had a bunch of threads on free VST hosts.)

To whom it may concern:
audacity is constantly being updated. since i started to use it, about 8 months ago (i think), it has changed A LOT. i've had trouble with all sorts of bugs and the only way i found to deal with them is, once it happens to you, just be aware of it and don't try it again. Then download the new version when it comes out. or, you know, wait till a couple new versions have come out and then d/l the latest. whatev. i'm just trying to say that just because you have a problem with a bug in audacity, don't freak out, it'll be fixed in a month.

Also, compressio is awesome. i'm just beginning to realize it's potential in songs with many tracks played at the same time.

Compression is standard in all of today's pop music, and, though not all sound engineers are actually fond of it, one has to go with the times.

Since audacity's compressor is quite simple, it's only natural that you can't hear much difference, unless you use extreme settings, or unless you are using super-expensive studio monitors, which I doubt any of us does. :?

The controls are as follows:

Threshold: Sets the decibel level at which the compressor starts to work. Drag the slider to the left, and compression will start working at less loud noises. Drag it to the right, and it will start compressing only the peaks.

Ratio: How much compression will be applied. No need to go into maths, 1.5:1 is almost not compressed, 10:1 is extremely compressed.

Attack: How fast the compressor will kick in. That's probably the hardest thing to set, along with release (which audacity doesn't have). Fast settings (left) will cut off the frequencies almost immediately, whereas slow settings(right), will make the compression more "fluid".

Normalize to 0db after compressing: Just brings your track to maximum level.

To listen to how it actually works, I would recommend trying it on a single instrument, like a bass line, with settings like -30db, 7:1, 1sec... should give heavy enough compression to realize the difference...

Anyway, I remember reading somewhere that good compression should be rather felt than heard, so maybe you're already doing everything perfectly!!! :lol:

Thanks for the explanations all, this has been bugging me for a while. Now I just have to figure out what a condenser does. :?

I still see DSP as somewhat of a mysterious black art.

Thanks for the explanations, FranticAerostat! That helps

Hey you know what, I would highly recommend you try out Bram's s(M)exoscope while learning how a compressor works, it will be very useful to actually see whats happening to your waveform while you're applying compression. It is also very useful to freeze the picture and determine exactly how many milliseconds there are between peaks such as drums or just in general to figure out your attack and release times.