delay1
delay1 — Delays an input signal by one sample.
Initialization
iskip (optional, default=0) -- initial disposition of delay-loop data space (see reson). The default value is 0.
Performance
delay1 is a special form of delay that serves to delay the audio signal asig by just one sample. It is thus functionally equivalent to the delay opcode but is more efficient in both time and space. This unit is particularly useful in the fabrication of generalized non-recursive filters.
Examples
Here is an example of the delay and delay1 opcodes. It uses the file delay1.csd.
Example 216. Example of the delay1 opcode.
See the sections Real-time Audio and Command Line Flags for more information on using command line flags.
<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform ; Audio out Audio in -odac ;;;RT audio out ; For Non-realtime ouput leave only the line below: ; -o delay1.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> ; by Menno Knevel 2021, after Russel Pinkston sr = 44100 ksmps = 32 nchnls = 2 0dbfs = 1 instr 1 ; original sounds ichoice = p4 if ichoice == 0 then prints "\n--**original beats**--\n\n" aout diskin2 "drumsMlp.wav" else prints "\n--**original noise**--\n\n" aout rand .2 endif outs aout, aout endin instr 2 ; Finite Impulse Response (FIR) Filter ichoice = p4 if ichoice == 0 then prints "\n--**FIRST-ORDER LOW-PASS on the beats**--\n\n" aout diskin2 "drumsMlp.wav" else prints "\n--**FIRST-ORDER LOW-PASS on the noise**--\n\n" aout rand .2 endif adel1 delay1 aout ; delay 1 sample asig = (.5* aout)+(.5* adel1) ; average 2 succesive inputs outs asig, asig endin instr 3 ; Finite Impulse Response (FIR) Filter ichoice = p4 if ichoice == 0 then prints "\n--**FIRST-ORDER HIGH-PASS on the beats**--\n\n" aout diskin2 "drumsMlp.wav" else prints "\n--**FIRST-ORDER HIGH-PASS on the noise**--\n\n" aout rand .2 endif adel1 delay1 aout ; delay 1 sample asig = (.5*aout)-(.5*adel1) ; difference of 2 inputs outs asig, asig endin instr 4 ; Finite Impulse Response (FIR) Filter ichoice = p4 if ichoice == 0 then prints "\n--**SECOND-ORDER NOTCH on the beats**--\n\n" aout diskin2 "drumsMlp.wav" else prints "\n--**SECOND-ORDER NOTCH on the noise**--\n\n" aout rand .2 endif adel1 delay1 aout ; x(n - 1) adel2 delay1 adel1 ; x(n - 2) asig = (.5*aout)+(.5*adel2) ; y(n) = .5x(n) + .5x(n - 2) outs asig, asig endin instr 5 ; Finite Impulse Response (FIR) Filter ichoice = p4 if ichoice == 0 then prints "\n--**SECOND-ORDER BAND-PASS on the beats**--\n\n" aout diskin2 "drumsMlp.wav" else prints "\n--**SECOND-ORDER BAND-PASS on the noise**--\n\n" aout rand .2 endif adel1 delay1 aout ; x(n - 1) adel2 delay1 adel1 ; x(n - 2) asig = (.5*aout)-(.5*adel2) ; y(n) = .5x(n) - .5x(n - 2) outs asig, asig endin </CsInstruments> <CsScore> i1 0 2 0 i1 3 2 1 s i2 1 2 0 i2 4 2 1 s i3 1 2 0 i3 4 2 1 s i4 1 2 0 i4 4 2 1 s i5 1 2 0 i5 4 2 1 e </CsScore> </CsoundSynthesizer>
This shows the result of the example: 5 times the beats and the noise. 1.Original samples, 2.first-order lowpass, 3.first-order highpass, 4.second-order notch and 5.second-order bandpass.
