add_misc_signal Subroutine

    subroutine add_misc_signal(tape, track, t1, t2, f, Amp, choice)
        type(tape_recorder), intent(inout) :: tape
        integer, intent(in)  :: track, choice
        real(wp), intent(in) :: t1, t2, f, Amp

        ! Pulsation (radians/second):
        real(wp) :: omega
        ! Time in seconds:
        real(wp) :: t
        real(wp), parameter :: phi = -3 * PI     ! Phase in radians at t=0
        integer  :: i, j

        omega = 2 * PI * f
        t = 0._wp
        do i = nint(t1*RATE), nint(t2*RATE)-1
            select case (choice)
                case (0) ! Pure sinus
                    tape%left(track, i) = + Amp * sin(omega*t + phi)
                case (1) ! Science fiction signal...
                    tape%left(track, i) = + Amp * sin(omega*t + phi*cos(75*t)/(1+log(t/100+0.01_wp)))
                case (2) ! Hummmmmmmmmm...
                    tape%left(track, i) = + Amp * sin(omega*t + phi*sin(omega*0.2_wp*t))
                case (3) ! UFO or siren?
                    tape%left(track, i) = + Amp * sin(omega*t + phi*cos(25*t))
                case (4) ! Noisy science fiction
                    tape%left(track, i) = + Amp * sin(omega*(1._wp + 0.2_wp*sin(t*50)) * t + phi)
                case (5) ! Whistling, slower and slower...
                    tape%left(track, i) = + Amp * sin(omega*(1._wp + 0.2_wp*sin(sqrt(t)*50)) * t + phi)
                case (6) ! Similar
                    tape%left(track, i) = + Amp * sin(omega*(1._wp + 0.2_wp*sin(log(t)*50)) * t + phi)
                case (7) ! Dudududududu...
                    tape%left(track, i) = + Amp * sin(t*30) * sin(omega * t + phi)
                case (8) ! Duuuuuuuuuuuuuuuuuuu
                    tape%left(track, i) = + Amp * sin(omega*t + phi*(0.5_wp+0.5_wp*sin(t*500)))
                case (9) ! A higher duuuuuuuuuuuuuuuuuuu
                    tape%left(track, i) = + Amp/2 * sin(omega*t + phi) + Amp/2 * sin(omega*1.1892_wp*t + phi)
                case (10) ! Higher and higher...
                    tape%left(track, i) = + Amp * sin((omega*(1+t/10)) * t + phi)
                case (11) ! Dampening slowly
                    do j=1, 7
                        tape%left(track, i) = + Amp/(j*(1+t**j))*sin(j*omega*t)
                    end do
                case (12) ! Vibrato
                    tape%left(track, i) = + Amp * sin(omega*t + phi*(1._wp + 0.5_wp*sin(2*PI*4*t)))
                case (13) ! A mix
                    tape%left(track, i) = + Amp * sin(t) * sin(omega*t + phi) &
                                   & + Amp * cos(2.5_wp*t) * sin(1.5_wp*omega*t + phi) + Amp * sin(3*t) * sin(2*omega*t + phi)
                case (14) ! Tremolo
                    tape%left(track, i) = + Amp * sin(omega*t + phi) + Amp * sin(1.001_wp*omega*t + phi) &
                                   & + Amp * sin(0.999_wp*omega*t + phi)
                case (15) ! Poke... (a short percussion based on the Sinc function)
                    if (omega*t+phi /= 0._wp) then
                        tape%left(track, i) = + Amp * sin(omega*t + phi) / (omega*t+phi)
                    else
                        tape%left(track, i) = + Amp
                    end if
                case (16) ! Science fiction, becoming higher and noisy
                    tape%left(track, i) = + Amp * sin(omega*(1._wp + 0.001_wp*sin(t*500)) * t + phi)
                case (17) ! Dissonant
                    tape%left(track, i) = + Amp*sin(omega*t + 4*sin(omega/10 * t))
                case (18) ! Dampening
                    tape%left(track, i) = + Amp*(1/(1+t**3))*sin(omega*t + 2*sin(omega*t+3*sin(omega*t)))
                case (19) ! Science-fiction, becoming higher and noisy
                    tape%left(track, i) = + Amp * &
                                   & sin(omega*(1._wp + 0.001_wp*sin(t*500*(1._wp + 0.0002_wp*cos(t*50)))) * t + phi)
                case (20) ! Another dampening sound
                    tape%left(track, i) = + Amp*(exp(-t)*sin(omega*t) + 0.5_wp*exp(-t**2)*sin(2*omega*t) &
                                   & + 0.25_wp*exp(-t**3)*sin(3*omega*t) + 0.12_wp*exp(-t**4)*sin(4*omega*t))
                case (21) ! Dampening slowly
                    do j=1, 14
                        tape%left(track, i) = + Amp/(j**2 * (1+t**j))*sin(j*omega*t)
                    end do
                case (22) ! Clarinet
                    do j=1, 11, +2
                        tape%left(track, i) = + Amp/j**0.7_wp * sin(j*omega*t)
                    end do
                case (23) ! Bessel function of the first kind J1: pong...
                    tape%left(track, i) = + Amp * bessel_jn(1, omega*t)
                case (24) ! Bessel functions of the first kind: ping (far shorter)
                    tape%left(track, i) = + Amp * bessel_jn(1, omega*t) * bessel_jn(2, omega*t)
            end select
            tape%right(track, i) = tape%left(track, i)
            t = t + dt
        end do
    end subroutine add_misc_signal