I have a memory of my dad's old Macintosh playing a custom sound every hour. It was his a capella rendition of the Westminster Quarters.

This was decades ago and my memory could be faulty. Was this feasible on a Mac made circa 1985-95? If so, was this a publicized feature or just something he did himself?

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    Why would it not be feasible on any computer that had sound hardware that could be used to play back recorded sound files? As it happens, I have a friend who had one of his computers playing back those bells, culminating in Big Ben, at least on the hour. (He demo'd it to me as a test of whether I, the Englishman, recognized it). It could have been on a Mac Pro or a DEC Alpha, I didn't ask/I don't recall.
    – dave
    Commented Oct 15, 2022 at 15:12
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    @another-dave, "Why would it not be feasible on any computer that had sound hardware that could be used to play back recorded sound files" Lots of reasons, really. For any computer, it may not have the RAM available for sound file playback, not have the software/OS support and capability without freezing the computer throughout playback and so on. That's a separate point to whether the Macs of the timeline here could do, too.
    – TonyM
    Commented Oct 15, 2022 at 17:28
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    @TonyM The mac had both, right from the start.
    – Raffzahn
    Commented Oct 15, 2022 at 17:40
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    @Raffzahn: Sound hardware yes. Memory, definitely not "from the start". Even if one tried to have the video frame interrupt synthesize sounds into a ~512-byte buffer, and could get the size of the sound code down to an additional 512 bytes, losing 1K of RAM on a Macintosh 128 would have substantially degraded its usefulness.
    – supercat
    Commented Oct 15, 2022 at 18:36
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    @Raffzahn: I suppose one could make an argument that the Macintosh didn't really "start" until the release of the Fat Mac, but I consider the Mac 128 part of the history of the platform, and it definitely did not have memory to be able to practically accommodate novelty INITs.
    – supercat
    Commented Oct 15, 2022 at 19:36

5 Answers 5


The Mac had the necessary soft- and hardware to play arbitrary sounds. It is said that the 8 bit/22 kHz DAC hardware was included on Steve Jobs' request especially for his "out of this bag" stunt, although Andy Herzfelds recollection tells this being exaggerated, but showing his dedication to the sound system.

Sound files were first class resources, supported by Toolbox(MacOS) calls right from the start, making it a much used feature right from the start. This included as well improved alarm clocks offering a hourly chime.

As so often Apple included successful features into the OS. I can't find the exact point quarter hourly chimes were first introduces as part of the OS, but by OS 8 (1997) the Clock Settings panel featured a section to assign arbitrary sounds to be played at :15, :30, :45 and full hour, titled Chime Settings.

Any installed sound could be used - including the quite popular

Westminster Chimes System Clock Sounds by Clixsounds of 1998

By OS 9 the dialog peaked:

OS9 Chime Dialog

In fact, when Apple dropped that feature in favour of a call out by speech synthesis in OSX, many users were rather disappointed, wanting their soundfiles back.

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    The hourly-chime program I used (SoundMaster) required IIRC WaveMaster-format sound files which kept audio data in the data fork. The Macintosh design requires that programs allow for the possibility that relocatable blocks of memory may be moved any time certain function calls are made, but allows programs to assume blocks won't be moved at other times. Asynchronous event handlers must therefore refrain from any action that might cause memory to be rearranged when the underlying application isn't expecting it.
    – supercat
    Commented Oct 15, 2022 at 18:40
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    This facility, along with the early network time sync program TimeLord, may or may not have been used in a large educational Mac lab to ensure that all of the machines emitted a colossally loud WildEep at exactly 10:15 every day
    – scruss
    Commented Oct 15, 2022 at 21:49

For awhile in the 1990s, I had SoundMaster installed on my Macintosh, and configured to play some sound files I'd synthesized every 15 minutes. I had to disable it when I needed as much memory as possible, and after while I stopped re-enabling it, but programs such as you describe definitely existed.

One difficulty with such programs is that such sounds may be triggered at times when it would not be safe to request disk access(*), and thus any sounds they may wish to play would have to be kept loaded at all times. On a system with four megabytes of RAM, the memory cost may exceed the coolness factor. Still, such programs did exist and at least some people actually used them.

(*) In order to accommodate rather tight memory constraints, the MacOS is designed around the idea that applications will generally allocate relocatble chunks of storage identified by handles. A program may read the address of storage identified by a handle, and assume the address won't change unless some operation is performed that would access memory. Because an attempt to access a disk may cause the system to pop up a dialog box, which would in turn require allocating storage for associated data structures, disk operations were included as being among those that might access storage (and potentially cause the addresses associated with handles to change). Doing this at a time when an application is relying upon a pointer to storage remaining valid would be disastrous.

Although the MacOS did include a function to lock the storage associated with a handle, reading and using the handle pointer without locking was common and accepted practice in situations where there would be no intervening operations that might allocate storage.

  • "At times when it would not be safe to request disk access". Most OSes I've used have ways to defer processing to a safe state. Not the Mac OS?
    – dave
    Commented Oct 15, 2022 at 19:08
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    @another-dave: Classic MacOS only had cooperative multitasking, unlike present-day OSes. There probably were times at which it was unsafe for an add-on that wasn't the main application running to access the disk. It certainly could not rely on being able to access the disk continuously for several seconds. Commented Oct 15, 2022 at 19:33
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    @another-dave: The Macintosh allowed applications to allocate relocatable blocks of storage, with a proviso that if they weren't explicitly locked they might move any time memory is allocated. It had a list of functions that might allocate memory, but specified that applications could assume that blocks would not spontaneously move at other times. Because disk operations might need to trigger a "Please insert disk X" dialog, they were among the things that might allocate memory.
    – supercat
    Commented Oct 15, 2022 at 19:39
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    @another-dave So did MacOS. Point here is less about detecting that, then such being guaranteed within certain time. While MacOS delivered a great deal of virtualization, it completely sucked at real time requirements. It wasn't until System 7 (IIRC) that reliable timing critical software (aka multimedia) could be done without hacks.
    – Raffzahn
    Commented Oct 15, 2022 at 22:48

If it was 1985, it had to be an original Mac, or maybe a Mac Plus or SE slightly after.

Those devices did have sample playback capability -- 8 bits, 22 kHz -- and a built-in speaker.

They did not have multi-tasking (until the Multi-Finder in some later system version,) BUT they had an interesting hot-patching strategy, where the OS would load extensions (called INITs) as it started up, and those extensions could hook into almost any part of the system.

There were INITs to make the trash can play a Grinch animation when emptying it. There were INITs to make the computer play clacky sounds when typing on the keyboard. There were INITs to help debug software, to play pranks, to look up documentation files, to connect to networks, and do a number of other things.

So, was there an INIT that played a sound every hour? I can't recall one, but I'm pretty sure one must have existed, because it wouldn't have been very hard to create, and an hourly "chime" sounds like something people would want.

  • 1
    MultiFinder was added in System 5 apparently (System 6 was the oldest I ever used and I mostly used System 7 on the Mac SE in question.). Here's the release announcement that Wikipedia cites for that.
    – ssokolow
    Commented Oct 16, 2022 at 5:59
  • There certainly was an extension that played a sound on the hour, because I can remember experimenting with it in the 1993-96 timeframe. This would have been on Classic or SE Macintoshes, running System 6 with the original single Finder.
    – john_e
    Commented Feb 6, 2023 at 15:28

I have a dim memory about SuperClock by Steve Christensen being able to play sound (resources) from the System file depending on the clock.


On my old Macs you simply could set the computer to tell the time up to every quarter of the hour. It was also possible to choose and even record the sound. I recorded different singing bowls for the whole, half, first and last quarters and that was really nice. Apple foolishly removed this option somewhere - during the nineties. Since there has been no free and problem free app for this simple feature which makes it possible to not laboriously have to set your alarm clock. The Tibetan singing bowls sounded even more great than a grandfather clock does. It would be nice to get this back in every version of OS that's still working. It seems such a simple gesture that gives so much.


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