• Flanger
• Chorus
• Phaser
• Noise Reduction
• Karaoke

dsp.zip 308 Kb

System requirements: Pentium 166+ for 44k1 stereo dsp, (although you can try a 486 at 22 Khz mono), full-duplex 16 bits soundcard, windows 95+

Depending on your hardware you can increase or decrease buffer sizes, nr buffers used and your numbers of pre filled buffers.
Especially, if you want to use this dsp real-time, try to reduce your buffer size and use 44k1 stereo.
The latency can be about 40-70ms up to 300 ms.
Normal settings are:
Buffer Size:32-1024 byte;
Prefill- bufs: 50-350; (increase prefill as buffersize decreases and vice versa);
Number of buffers (200-1000);
I've given full control over these hardware settings to make it run optimal on different systems.
One can not say which settings are 'best' - try, because it's rather safe. Look at the presets to understand the relations (especial memory consumption). Don't make your prefill bigger than about half the amount of buffers used.

Please be aware that this program can take up to 100% processor time, and always should be terminated normally, which as far as I know, it always will.
I disabled the save-to-file function in this version, since this was rather system recource consuming and therefore a bit tricky.

LFO
The shape of the LFO has also influence,
Triangle , sinus  and exponential  shapes are common used.
For the chorus/flanger I used a triangle LFO shape. For the phaser an exponential LFO shape (typical for a phaser).

A Chorus adds a vibrating -almost- echo to the signal (the delay is too short for your ears to hear it as a delay). So a voice sounds as if two people are singing, or two people sound like a chor. Or a guitar is some more 'full' as if there were two.

A phaser uses a very short delay. This way, some frequency's get filtered out (if the delay is the same as one half wavelength the frequency is filtered out). Because the delay is changing, it gives a very 'spacy' sound. Apply it on a drum or on a whole mix.

A flanger is- in my opinion, just weird. But you may like the sound. By setting the initial delay to almost zero, it will act a bit as if it were a phaser. With another LFO wave type though.
Nice for guitar effects or 'scrambled' voice.

Depending on the settings you can get different effects.

Typical settings for Phaser, Flanger and Chorus are:

Effect	Volume	Initial Delay	LFO	Depth
Phaser:	0 dB added to input	7KHz-200Hz	< 0.5 Hz	1/10-1/3 of max.
Chorus:	-3 - 0 dB	20-30 ms	<0.5-2 Hz	+-2.5 ms
Flanger:	-10 - -3 dB	<5ms	Free	Big?

Please Note that if you reduce the depth of the Effect to 0, the remaining thing is an ordinary echo.