TweetFollow Us on Twitter

Sound 101
Volume Number:9
Issue Number:3
Column Tag:C Workshop

Related Info: Sound Manager

Sound 101

Evolution of the Mac voice

By Iggi Monahelis, Pleasanton, California

Note: Source code files accompanying article are located on MacTech CD-ROM or source code disks.

About the author

Iggi Monahelis is a programmer who bought his first Mac as soon as he could back in 1984. He is the principal designer and co-author of “Read My Lips”, the sound annotation utility for the Macintosh.

Introduction

This is an introductory article, hence the name Sound 101, dealing with basic recording and playback of sounds on the Macintosh. It explains the required steps to be taken in order to digitize sounds using a microphone, in two different sound formats, and play them back. It is a good stepping stone for someone who has little or no knowledge of how to do these things in a program on the Macintosh. As a matter of fact, one can probably copy the routines given in the article, and use them in their own program without a lot of modifications.

Ancient History

The Macintosh has had the capability of producing sounds since day one. The famous introduction of the Macintosh back in 1984 used sound, in the form of digitized speech, to allow the Mac to introduce itself. Inside Macintosh back then had a chapter on the Sound Driver with just a few routines, literally StartSound, StopSound and SoundDone, that allowed the programmer to control the Sound Driver. The Sound Driver produced sound using three different sound synthesizers:

1) the four-tone synthesizer, used to make simple harmonic tones, with up to four “voices” producing sound simultaneously. Hence the name four-tone.

2) the square-wave synthesizer, used to produce sounds such as beeps.

3) the free-form synthesizer, used to produce complex sounds, music and speech.

You had to “describe” the sound to the Driver as a waveform, basically fill a buffer with a bunch of numbers, and tell the Sound Driver to start producing noise based on these numbers. Very primitive.

Middle Ages

With the introduction of the Macintosh II class of machines, the Sound Driver had graduated to the Sound Manager. It was indeed a graduation because several innovations had taken place:

1) The hardware now included a new sound chip which freed the machine’s processor from doing all the work.

2) The introduction of sound resources. Sound resources can “contain” any sound you can imagine, from a simple beep sound to digital recordings of CD’s. And because they are resources, in the Macintosh sense of the word, you can work with them using standard Resource Manager calls. To play a sound resource all you have to do is load it and pass the handle to the resource to the SndPlay routine.

3) The Sound Manager now has seven routines to allow you to work with sound.

To produce sound, commands are sent to a synthesizer, as was the case with the Sound Driver. The Sound Manager uses a queue to send these commands to a synthesizer, these queues are called channels. To make complex sounds, many sounds may need to be produced simultaneously. For this reason several synthesizers can have multiple channels.

The new Sound Manager uses three synthesizers to produce sound:

1) the wave-table synth, lets you supply a wave table that describes the sound. This lets you produce more complex sounds, also it lets you play multiple sounds simultaneously by opening several channels. It corresponds to the old four-tone synth with four channels open.

2) the note synth, used to produce simple sounds, such as a note. The note synth can produce only one note at a time. It compares to the old square-wave synth from the Sound Driver.

3) the sampled sound synth, used to play digitally recorded sounds. In this case instead of passing the note or a wave table describing the sound you want played, you pass a buffer that contains samples of the sound to be played. This synth compares to the old free-form synth from the Sound Driver.

Despite the innovations that came with the Mac II and the graduation of the Sound Driver to a Manager, it was still difficult to digitize sounds using System software. It was easy once you had a sound resource to play it and several programs, mostly shareware, were created to play sound resources. Farallon came out with the MacRecorder® sound digitizer which allowed you to digitize sounds using the software that came with it, but still you could not do that in your own program without writing a lot of code yourself.

Today

With the introduction of the Macintosh IIsi and Macintosh LC, Apple for the first time included a built-in microphone with the Macintosh. System software versions 6.0.7 and later have a new and improved version of the Sound Manager. The Sound Manager chapter goes from 32 pages to 114 pages. This latest version introduces a whole slew of new features, some of which are:

1) There are now routines to record sounds using the built-in microphones, or any third party microphone with the appropriate driver for Macs that do not come with a microphone.

2) One can record either sound resources (‘snd ‘), or record directly to a file on disk in a format known as: Audio Interchange File Format (AIFF).

3) There are routines that allow for compressing and decompressing of sound data.

4) There are now routines that allow for the playing of sounds directly from disk. So one does not have to load all of the sound in memory in order to play it.

5) Customization galore. Besides the high-level routines for recording and playback there are low-level routines so that one could customize the way recording and playback is done.

Writing the program

It is always easier to start with a basic program, understand it, and then expand on it. The Sound 101 program is just such a program for learning the basics about recording and playing sounds. The program can record and play 'snd ' and AIFF sound files. It also allows for the selection of sound quality.

Here goes the code with explanations...

Sound101_main.c
/***********************************************************
© 1992 Praxitel, Inc. and Iggi Monahelis

This is the “main” for the Sound 101 project.  It has the minimum stuff 
to get a mac
program going.  Basically, it does all the required mac initializations, 
sets up the menu
bar, and then gets and processes events.

***********************************************************/
#include “Sound101.h”


extern int  gDestroyChannel;
extern SndChannelPtr gSndChan;
extern short     gFRefNum;
extern long gQuality;

/***********************************************************

main

This is the main routine for the Sound 101 application, it does all the 
Mac initializations.
Then calls the EventLoop procedure to get and process events.

***********************************************************/
void main(void)
{
 InitGraf((Ptr) &thePort );
 InitFonts();
 InitWindows();
 InitMenus();
 TEInit();
 InitDialogs(0L);
 InitCursor();
 
 MaxApplZone();
 SetUpMenus();

 EventLoop();    /* Do event processing until user quits */

}

/***********************************************************

SetUpMenus

Set up the menu bar for the Sound 101 application
 
***********************************************************/
void SetUpMenus(void)
{
 MenuHandle myMenu;
 
 myMenu = GetMenu(mApple);
 
 AddResMenu( myMenu, ‘DRVR’ );
 InsertMenu( myMenu, 0 );
 InsertMenu(GetMenu(mFile), 0) ;
 DrawMenuBar();
}

/***********************************************************

EventLoop

Event handling for the Sound 101 application.
Get events forever, and handle them by calling DoEvent.
 
***********************************************************/
void EventLoop(void)
{
 BooleangotEvent;
 EventRecordevent;

 do {
 gotEvent = WaitNextEvent(everyEvent, &event, 50, 0);
 if ( gotEvent ) {
 DoEvent(&event);
 }
 /* if we are done with the sound, dispose the sound 
    channel and close the sound file. */     
 if ( gDestroyChannel ) { 
 OSErr  myErr;
 
 InitCursor();
 if (gSndChan)
 myErr = SndDisposeChannel( gSndChan, TRUE);
 if (gFRefNum)
 myErr = FSClose(gFRefNum);
 /* make sure we do it only once! */
 gDestroyChannel = FALSE;
 gSndChan = 0;
 gFRefNum = 0;
 } 
 } while ( true ); /* loop forever */
} /*EventLoop*/

/***********************************************************

DoEvent

Determine the event type and dispatch accordingly
 
***********************************************************/
void DoEvent(EventRecord *event)
{
 short  part, err;
 WindowPtrwindow;
 char   key;

 switch ( event->what ) {
 case nullEvent:
 break;
 case mouseDown:
 part = FindWindow(event->where, &window);
 switch ( part ) {
 case inMenuBar:
 /* process a mouse menu command */
 DoMenuCommand(MenuSelect(event->where));
 break;
 case inSysWindow:
 /* let the system handle the mouseDown */
 SystemClick(event, window);
 break;
 case inContent:
 break;
 case inDrag:                
 break;
 case inGoAway:
 break;
 case inGrow:
 break;
 case inZoomIn:
 case inZoomOut:
 break;
 }
 break;
 case keyDown:
 case autoKey:
 /* check for menukey equivalents */
 key = event->message & charCodeMask;
 if ( event->modifiers & cmdKey ) {
 /* Command key down */
 /* if command-period was pressed, set our global
    to clean up the sound channel and close the
    open sound file. */
 if ( key == ‘.’ )
 /* command period was pressed */
 gDestroyChannel = TRUE;
 }
 break;
 case activateEvt:
 break;
 case updateEvt:
 break;
 }
} /*DoEvent*/

/***********************************************************

DoMenuCommand

Handles menu selections for the Sound 101 application
   
***********************************************************/
void DoMenuCommand(long menuResult)
{
 short  menuID, menuItem;
 short  itemHit, daRefNum;
 Str255 daName;

 menuID = HiWord(menuResult);
 menuItem = LoWord(menuResult);
 switch ( menuID ) {
 case mApple:
 switch ( menuItem ) {
 case iAbout: {  /* bring up the About box */
 OSErr  err;
 GrafPtroldPort;
 Rect   tempRect;
 DialogPtraboutDlg;
 
 GetPort(&oldPort);
 
 aboutDlg = GetNewDialog(128, nil, (WindowPtr) -1);
 if ( aboutDlg ) {
 /* Open a dialog box */
 ShowWindow(aboutDlg);    
 SelectWindow(aboutDlg);  /* Lets see it */
 SetPort(aboutDlg);
 while (TRUE) {
 ModalDialog(NULL, &itemHit);
 if ( itemHit == 1 )
 break;
 }
 DisposDialog(aboutDlg);
 SetPort(oldPort);
 }
 }
 break;

 default:
 /* all non-About items in this menu are DAs */
 GetItem(GetMHandle(mApple), menuItem, daName);
 daRefNum = OpenDeskAcc(daName);
 break;
 }
 break;
 
 case mFile:
 switch ( menuItem ) {
 case iPlaySound:
 PlayASound();
 break;
 case iRecordsndSound:
 Record_snd_resource(gQuality);
 break;
 case iRecordAIFFSound:
 Record_AIFF_sound(gQuality);
 break;
 case iQuality:
 GetQuality();
 break;
 case iQuit:
 Terminate();
 break;
 }
 break;
 } 
 
 /* unhighlight what MenuSelect (or MenuKey) hilited */
 HiliteMenu(0);  
}

/***********************************************************

Terminate

Quit the app
   
***********************************************************/
void Terminate(void)
{
 /* exit if no cancellation */
 ExitToShell();  
} /*Terminate*/
 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Viber 11.9.1 - Send messages and make fr...
Viber lets you send free messages and make free calls to other Viber users, on any device and network, in any country! Viber syncs your contacts, messages and call history with your mobile device, so... Read more
Vallum 3.3.2 - $15.00
Vallum is a little tool that helps you monitor and block apps connections and throttle apps bandwidth. It is able to intercept connections at the application layer, and hold them while you decide... Read more
Microsoft OneNote 16.31 - Free digital n...
OneNote is your very own digital notebook. With OneNote, you can capture that flash of genius, that moment of inspiration, or that list of errands that's too important to forget. Whether you're at... Read more
Apple Pages 8.2.1 - Apple's word pr...
Apple Pages is a powerful word processor that gives you everything you need to create documents that look beautiful. And read beautifully. It lets you work seamlessly between Mac and iOS devices, and... Read more
Numbers 6.2.1 - Apple's spreadsheet...
With Apple Numbers, sophisticated spreadsheets are just the start. The whole sheet is your canvas. Just add dramatic interactive charts, tables, and images that paint a revealing picture of your data... Read more
f.lux 39.9873 - Adjusts the color of you...
f.lux makes the color of your computer's display adapt to the time of day, warm at night and like sunlight during the day. Ever notice how people texting at night have that eerie blue glow? Or wake... Read more
Deeper 2.5.0 - Enable hidden features in...
Deeper is a personalization utility for macOS which allows you to enable and disable the hidden functions of the Finder, Dock, QuickTime, Safari, iTunes, login window, Spotlight, and many of Apple's... Read more
NTFS 15.5.71 - Provides full read and wr...
NTFS breaks down the barriers between Windows and macOS. Paragon NTFS effectively solves the communication problems between the Mac system and NTFS. Write, edit, copy, move, delete files on NTFS... Read more
MTR 5.3.0.0 - The Mac's oldest and...
MTR (was MacTheRipper)--the Mac's oldest and smartest DVD-backup app. MTR - the complete toolbox, not a one-trick, point-and-click extractor. MTR is intended for making fair-use, backup copies of... Read more
Keynote 9.2.1 - Apple's presentatio...
Easily create gorgeous presentations with the all-new Keynote, featuring powerful yet easy-to-use tools and dazzling effects that will make you a very hard act to follow. The Theme Chooser lets you... Read more

Latest Forum Discussions

See All

Black Desert Mobile gets an official rel...
Pearl Abyss has just announced that its highly-anticipated MMO, Black Desert Mobile, will launch globally for iOS and Android on December 11th. [Read more] | Read more »
Another Eden receives new a episode, cha...
Another Eden, WFS' popular RPG, has received another update that brings new story content to the game alongside a few new heroes to discover. [Read more] | Read more »
Overdox guide - Tips and tricks for begi...
Overdox is a clever battle royale that changes things up by adding MOBA mechanics and melee combat to the mix. This new hybrid game can be quite a bit to take in at first, so we’ve put together a list of tips to help you get a leg up on the... | Read more »
Roterra Extreme - Great Escape is a pers...
Roterra Extreme – Great Escape has been described by developers Dig-It Games as a mini-sequel to their acclaimed title Roterra: Flip the Fairytale. It continues that game's tradition of messing with which way is up, tasking you with solving... | Read more »
Hearthstone: Battlegrounds open beta lau...
Remember earlier this year when auto battlers were the latest hotness? We had Auto Chess, DOTA Underlords, Chess Rush, and more all gunning for our attention. They all had their own reasons to play, but, at least from where I'm standing, most... | Read more »
The House of Da Vinci 2 gets a new gamep...
The House of Da Vinci launched all the way back in 2017. Now, developer Blue Brain Games is gearing up to deliver a second dose of The Room-inspired puzzling. Some fresh details have now emerged, alongside the game's first official trailer. [Read... | Read more »
Shoot 'em up action awaits in Battl...
BattleBrew Productions has just introduced another entry into its award winning, barrelpunk inspired, BattleSky Brigade series. Whilst its previous title BattleSky Brigade TapTap provided fans with idle town building gameplay, this time the... | Read more »
Arcade classic R-Type Dimensions EX blas...
If you're a long time fan of shmups and have been looking for something to play lately, Tozai Games may have just released an ideal game for you on iOS. R-Type Dimensions EX brings the first R-Type and its sequel to iOS devices. [Read more] | Read more »
Intense VR first-person shooter Colonicl...
Our latest VR obsession is Colonicle, an intense VR FPS, recently released on Oculus and Google Play, courtesy of From Fake Eyes and Goboogie Games. It's a pulse-pounding multiplayer shooter which should appeal to genre fanatics and newcomers alike... | Read more »
PUBG Mobile's incoming update bring...
PUGB Mobile's newest Royale Pass season they're calling Fury of the Wasteland arrives tomorrow and with it comes a fair chunk of new content to the game. We'll be seeing a new map, weapon and even a companion system. [Read more] | Read more »

Price Scanner via MacPrices.net

Weekend Sale: Apple AirPods Pro for $234.98 a...
Abt Electronics has Apple’s new AirPods Pro in stock and on sale today for $234.98 including free shipping and free returns. Their price is $15 off Apple’s MSRP for these AirPods and tie Amazon... Read more
New 2019 16″ MacBook Pros on sale for $100 of...
Apple Authorized Reseller Adorama has new 2019 16″ MacBook Pros on sale today for $100 off Apple’s MSRP, each including free shipping. In addition, Adorama charges sales tax for NY & NJ residents... Read more
Apple Watch Series 3 GPS models on sale for l...
Amazon has Apple Watch Series 3 GPS models on sale starting at only $179. There prices are the lowest we’ve ever seen for these models from any Apple reseller. Choose Amazon as the seller rather than... Read more
iOS Bug In Facebook News Feed Lets Device Ca...
NEWS: 11.15.19- Users of the Facebook social media platform’s mobile app running on iOS devices won’t, like, this piece of news one bit in where a bug in the News Feed gave access to the camera... Read more
16″ MacBook Pros on sale! Preorder at Amazon...
Apple’s new 16″ MacBook Pros were only introduced yesterday, but Amazon is already offering a $100 discount on preorders. Prices for the base 6-Core 16″ MacBook Pros start at $2299: – 2019 16″ 2.6GHz... Read more
Use our exclusive MacBook Price Trackers to f...
Our Apple award-winning MacBook price trackers are the best place to look for the best sales & lowest prices on new and clearance MacBook Airs and MacBook Pros–including Apple’s new 16″ MacBook... Read more
New November Verizon iPhone deal: Get an iPho...
Verizon has the 64GB iPhone Xr on sale for 50% off for a limited time, plus they will include a free $200 prepaid MasterCard and a free Amazon Echo Dot. That reduces their price for the 64GB iPhone... Read more
Apple cuts prices on clearance, refurbished 2...
Apple has clearance 2018 15″ 6-Core Touch Bar MacBook Pros, Certified Refurbished, now available starting at only $1829. Each model features a new outer case, shipping is free, and an Apple 1-year... Read more
Up to $450 price drop on clearance 15″ MacBoo...
B&H Photo has dropped prices Apple’s 2019 15″ 6-Core and 8-Core MacBook Pros by $400-$450 off original MSRP, starting at $1999, with free overnight shipping available to many addresses in the US... Read more
Here’s how to save $200 on Apple’s new 16″ Ma...
Apple has released details of their Education discount associated with the new 2019 16″ 6-Core and 8-Core MacBook Pros. Take $200 off the price of the new 8-Core model (now $2599) and $200 off the 16... Read more

Jobs Board

Best Buy *Apple* Computing Master - Best Bu...
**746887BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Store Associates **Store NUmber or Department:** 001512-Ankeny-Store **Job Read more
Best Buy *Apple* Computing Master - Best Bu...
**746836BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Sales **Store NUmber or Department:** 000341-Scranton-Store **Job Description:** **What Read more
QA Manager, *Apple* - CBS Corporation (Unit...
# QA Manager, Apple **REF#:** 35331 **CBS BUSINESS UNIT:** CBS Interactive **JOB TYPE:** Full-Time Staff **JOB SCHEDULE:** **JOB LOCATION:** Burbank, CA **ABOUT Read more
*Apple* Mobility Pro - Best Buy (United Stat...
**744315BR** **Job Title:** Apple Mobility Pro **Job Category:** Store Associates **Store NUmber or Department:** 000662-Auburn AL-Store **Job Description:** At Best Read more
Nurse Practitioner - Field Based (San Bernard...
Nurse Practitioner - Field Based (San Bernardino, CA, Apple Valley, Hesperia) **Location:** **United States** **New** **Requisition #:** PS30312 **Post Date:** 4 Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.