[Csnd] port opcode and envelopes
| Date | 2021-01-12 16:13 |
| From | Bernard Geyer |
| Subject | [Csnd] port opcode and envelopes |
In my midi-controlled instruments, the amplitude is determined by 3 factors : midi velocity, a slider for each channel and a master slider. The velocity is determined at i rate and the slider values at k rate. I use the CsoundQt GUI sliders. In order to avoid clicks when I move sliders, I use the port opcode, and I first tried the port time 0.05 that is given in some examples. The clicks are gone, but there are 2 new problems : - on instruments with a short attack, the original attack is destroyed and replaced by a more slow attack - on instruments with very few overtones, specially sinus-like; there are artefacts on each segment of the envelope. With port time 0.01, the attack is still not correct. With port time 0.001, there are clicks when I move the sliders . So, I choosed 0.005 as a compromise. Here is an example of my code : opcode Oscillator, aa, iiiii iChannel, iKey, iVelocity, iGain, iWaveform xin ;(other parameters are stored in tables): SetKeyParam(iChannel, iKey, giNumChannels, 1) iTuning = GetKeyParam(iChannel, iKey, giTuning)
kEnv = kADSR(iChannel, iKey) iVelo = (iVelocity / 127) iVelo *= iVelo ;squared kAmp = iGain * iVelo * \ GetKeyParam(iChannel, iKey, giVolume) * \ kGetChannelParam(iChannel, giChannelVolume) * \ kGetChannelParam(0, giChannelVolume) ; 0 = master volume kAmp port kAmp, 0.005 ; smooth audio_vol aSig poscil kAmp * kEnv, iTuning, iWaveform
xout aSig, aSig endop In some instruments I use poscil, in others loscil, without difference concerning this problem. Some ideas ? |
| Date | 2021-01-12 20:46 |
| From | Tarmo Johannes |
| Subject | Re: [Csnd] port opcode and envelopes |
Hi! three things to try - - use a-rate for amplitude and envelope, use interp(kamp), if necessary - depending on ksmps, it can give audible steps when changing - try to use the init value parameter in the port opcode - otherwis it starts always from 0. I am not sure if it helps but you can to determine what is the value in i-time and start form that: iAmp = iGain * iVelo * \ GetKeyParam(iChannel, iKey, giVolume) * \ iGetChannelParam(iChannel, giChannelVolume) * \ iGetChannelParam(0, giChannelVolume) kAmp = ... kAmp port kAmp, 0.02, iAmp I often use lines like: kVolume port chnget:k("volume"), 0.02, chnget:i("volume") to smoothen values coming from channels - Try lag opcode instead: Hope it helps! tarmo T, 12. jaanuar 2021 18:14 Bernard Geyer <micamusic2@gmail.com> kirjutas:
|
| Date | 2021-01-12 21:28 |
| From | Eduardo Moguillansky |
| Subject | Re: [Csnd] port opcode and envelopes |
|
As Tarmo said, port alone is not what you need. At least
interp(port(...)). A better solution is lag, which is audio-rate.
On 12.01.21 17:13, Bernard Geyer wrote:
|
| Date | 2021-01-15 21:59 |
| From | Justin Smith |
| Subject | Re: [Csnd] port opcode and envelopes |
this makes me think that the velocity is fed into the same port that the sliders do - this is incorrect IMHO, dynamic runtime controls should be smoothed by port, but the velocity should be a separate factor with no port smoothing. |