(See also _H_e_l_p files for _r_t, _r_t_t_e_m_p_l_a_t_e and _r_t_o_p_e_n.)

Synopsis:  In a shell window, type:    rtlearn  

This utility will copy a tutorial _r_t mix specification  file
called _l_e_a_r_n._r_t into your current working Unix directory. To
use this file, first launch _r_t. Then, to  read  in  the  mix
data from the _l_e_a_r_n._r_t file into the initially blank _r_t win-
dows, use the customary _O_p_e_n command  under  the  _F_i_l_e  menu
(or  else  type  the  _A_l_t  and  _f keys) and select the input
script file _l_e_a_r_n._r_t. The  _S_o_u_n_d_f_i_l_e  and  _P_l_a_y_n_o_t_e  windows
should  fill  with  data.  Tap the _L_o_a_d _e_v_e_r_y_t_h_i_n_g button to
prepare the mix for execution.

This mix includes  five  input  soundfiles  from  the  _s_f_l_i_b
directories. Within the _S_o_u_n_d_f_i_l_e_s window,
     /_s_f_l_i_b/_v_o_i_c_e/_s_o_p_2._a_4  is defined as _s_n_d _1
     /_s_f_l_i_b/_e_n_v/_S_T_f_o_r_e_s_t  is defined as _s_n_d _2
     and a bongo roll, a grindingwheel  and  the  critically
     acclaimed  _v_o_i_c_e_t_e_s_t  soundfile  are  assigned, respec-
     tively, to _s_n_d numbers 3, 4 and 5.

     The playnote window  includes  8  lines.  Initially,  I
recommend  that  you mute some of the tracks (perhaps tracks
4, 5 and 6) by clicking on these numbers in the  _T_r_a_c_k  _c_o_n_-
_t_r_o_l  area  of  the main window so that they turn pink. Also
try using the _P_l_a_y _f_r_o_m and _P_l_a_y _t_o  options to play only  a
portion of the mix.

     The first three playnotes create a three  note  soprano
chord  from  a  single input soundfile (with different pitch
transpositions) on tracks 1, 11  and  12.   _S_T_f_o_r_e_s_t,  which
begins  playing  at 3 seconds into the mix  on track 2, is a
stereo soundfile, and thus does not require a _p_a_n  argument.
The  playnote arguments for the bongo roll soundfile, played
on track 3, are straightforward.

     Track 4,  _g_r_i_n_d_i_n_g_w_h_e_e_l :
_p_l_a_y_n_o_t_e(_t_r_a_c_k=_4,_s_n_d=  _4,  _a_t=_6  ,_d_u_r=  _5._2,  _a_m_p(_0,_0,._3,._9,
._7,._2_5, _1.,_0),_p_a_n = ._2) // _g_r_i_n_d_i_n_g_w_h_e_e_l
Only the first 5.2 seconds of this long soundfile are  used.
Since  this  fragment  will  not  end with zero amplitude, a
click will result at the end unless we  apply  an  amplitude
fade-out.  Although not required, we also have chosen to add
a fade-in during the first 30 % of the 5.2 second  duration,
up  to a peak value of 90 % of the original amplitude level.
During the next 40 % of the  total  5.2  second  duration  -
between  relative times .3 (30 %) and .7 (70 %) - the ampli-
tude decreases to 25 % of the  input  values.  The  fade-out
occurs during the last 30 % of this amplitude envelope.
(Note: Alternatively, we  could  have  used  absolute  times
between  0 and 5.2, rather than relative times between 0 and
1., within our _a_m_p arguments.)

Track 5,  _v_o_i_c_e_t_e_s_t :
_p_l_a_y_n_o_t_e(_t_r_a_c_k=_5 ,_s_n_d= _5,  _a_t=  _1_0._0,  _s_k_i_p  =  _1,_e_n_d=_3._9  ,
_a_m_p_l(_0,_0,._2,._5,_1.,_0),_a_m_p_r(_0,_0,._2,_0,   ._9,  ._5,  _1.,  _0))  //
_v_o_i_c_e_t_e_s_t
The first one second of this soundfile is skipped, and  only
the next 2.9 seconds of the original sound are read in. (The
_e_n_d time argument specifies the  time  within  the  original
soundfile to stop reading):

Thus, an amplitude fade-in and a fade-out both are necessary
to avoid clicks.  Instead of applying a single _a_m_p envelope,
however, we have created separate  amplitude  envelopes  for
the left channel (_a_m_p_l) and right channel (_a_m_p_r) outputs, in
order to move the signal from left to right.

Track 6, recapitulation,  _s_o_p_2._a_4 :
_p_l_a_y_n_o_t_e(_t_r_a_c_k=_6 ,_s_n_d= _1, _a_t= _1_2 ,  _d_u_r=_4,  _g_l_i_s_s(_0,-_2,  ._3,
-_2, ._7, _4, _1.,_4),_g_a_i_n = ._3,_p_a_n=._9_9, _a_m_p(_0,_1,._9_6,_1, _1.,_0)) //
_s_o_p_2._a_4
We could have used track 1, rather than track  6,  for  this
input had we wished, since no sound is playing on track 1 at
12 seconds into the mix. (For that  matter,  several  previ-
ously used tracks are available for re-use at this point.)
A pitch glissando is applied, beginning a major second below
the original pitch level, then rising, between 30 % and 70 %
of the way throughy the soundfile, up a tritone to  a  final
transposition  level a major third (4 semitones) higher than
the original pitch.
The original version of this  command  line  -  all  that  I
really want to specify - looked like this:
_p_l_a_y_n_o_t_e(_t_r_a_c_k=_6 ,_s_n_d= _1, _a_t= _1_2 , _g_l_i_s_s(_0,-_2, ._3,  -_2,  ._7,
_4, _1.,_4),_g_a_i_n = ._3,_p_a_n=._9_9) // _s_o_p_2._a_4
However, as sometimes happens during resampling pitch  glis-
sandi  or  transposition operations within _r_t, this resulted
in a glitch at the end of the soundfile.  To eliminate  this
vile  wart,  I  have limited the input _d_u_ration to 4 seconds
(the actual soundfile duration is 4.34  seconds),  and  then
have  applied  an  _a_m_p  fade-out during the last 4 % of this
duration.

Try editing (changing) some  of  these  playnote  arguments.
After each edit, tap the _R_e_l_o_a_d _p_l_a_y_n_o_t_e_s or _L_o_a_d _e_v_e_r_y_t_h_i_n_g
button before playing the new version.
