4-Fat demos, January 30, 1995
Halifax, Nova Scotia, Canada


For more information please contact
===================================

Digital Recordings - Advanced  R & D
5959  Spring Garden Road, Suite 1103
Halifax, Nova Scotia B3H-1Y5, Canada
Tel./ Fax.  (902)  429-9622
E-mail:  mmieszko@ac.dal.ca


DFG and DFG_RT software is now available for 4 architectures : 
==============================================================
NeXT, Intel, HP and Sun 
=======================

4-Fat demo software is available now via ftp or directly from 
Digital Recordings via NeXTmail. 

  
DFG - Introduction
==================

DFG_RTdemo.app is a demo module for real-time synthesis of the 
sinusoidal (pure tone) signal.Signals are generated in real time 
and do not require the DSP processor (which is not available in 
some NeXTSTEP computers).This version should work on all Motorola 
Intel, Sun and HP computers with NeXTSTEP versions 2.* => 3.* and
equipped with D/A converters. 

This program works very nicely with Digital Oscilloscope  and 
Spectrum Analyzer (both applications come with NeXT) and any 
recording / editing software. Playback and recording/analysis 
of the signal could be done simultaneously since DSP chip is not 
used and main processor is used only 2-3% during signal production.

DFG_RT is an ideal signal source for research and teaching in the 
fields of acoustics, psychoacoustics, electronics, electroacoustics,
physics, mechanics, vibration measurements, architecture, audiology 
and transducer testing. 


DFG Software  Specifications / Parameters
=========================================

o  Stereo output (independent R and L channel) 

o  Frequency adjustable continuously from 0 to 22,000 Hz.

o  Frequency stability : +/- 0.0001 Hz  at 1000 Hz 

o  Amplitude adjustable continuously from -140 to  0 dB  

o  Amplitude stability : +/- 0.00026 dB at 0 dB 

o  Phase adjustable continuously from 0 to 360 degrees.

o  S/N ratio = 95 dB


DFG_RT  Modules
===============

Currently there are 8 modules available in DFG_RT software :

DFG_RTsine.app		- for generating pure tones (1->22,000 Hz).
DFG_RTsquare.app	- for generating square wave (1->22,000 Hz).
DFG_RTtriangular.app	- for generating triangular wave (1->22,000 Hz).
DFG_RTsawtooth.app	- for generating sawtooth wave (1->22,000 Hz).
DFG_RTpulse.app		- for generating delta-pulse train (1->22,000 Hz).
DFG_RTnoise.app		- for generating white noise in 0->22,050 Hz 
                          range.
DFG_RTnoiseNB.app	- for generating narrow band noise from 
                          100->200 Hz to 11,000->22,000 range.
DFG_RTnoiseNBv.app	- for generating narrow band noise with 
                          bandwidth adjustable from 20 Hz to 2,000 Hz 
                          and center frequency adjustable from 1 Hz 
                          to 22,000 Hz.


DFGdemo.app and DFG_RTdemo.app are available on the following FTP sites
========================================================================
( please look for the files DFGdemo.app.tar.Z and DFG_RTdemo.app.tar.Z )

ftp://ftp.cs.orst.edu/pub/next/submissions

ftp://ftp.informatik.uni-muenchen.de/pub/comp/platforms/next/submissions

ftp://terra.stack.urc.tue.nl/pub2/next/submissions

==> Note 1:  Also, you can obtain latest software via NeXTmail
***********  directly from: mmieszko@ac.dal.ca

==> Note 2:  We are looking forward to feedback, specially from 
***********  users of NeXTSTEP on Sun and HP platforms on which 
             DFG software was not tested yet. Thanks in advance 
             for your help !