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Comment by roywashere | Hacker News Reader

> And there is the original Duke Nukem (DN1, DN2, and DN3) which I always would have liked to have the ability to turn down the volume for. Playing without sound effects was no fun and with sound effects was disturbing for the other people in the house.

Is there a good reason that most XT/AT era computers had no volume control for their PC speaker? I always wondered. My dad's XT had an incredibly loud speaker, I always felt bad playing Accolades Test Drive on it. When I finally bought my own XT I was very happy with the fact the speaker was a little less loud

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Somewhat. The internal speaker in the original PC was pretty much just a buzzer that was probably never intended to output anything else other than simple status beeps in office settings.

It does not even have the ability to modulate its amplitude, i.e. its voltage level is either "full on" or "full off" and tones are usually played by doing that, for example, 2000 times a second to get a 2kHz square wave tone. There seem to be some (likely rather PC model specific) tricks to toggle it quickly enough to get some in-between waveforms[1], but overall there are no "volume" levels.

While it's likely not very hard to have a circuit to manually reduce the overall amplitude[2], by the time this really became commonly desirable enough we probably all had sound cards anyway, if we wanted to play anything more prolonged than the system beep on it.

[1] By means of inertia, the mechanical kind or the electromagnetic kind.

[2] Or even in software, but nothing would support that.

This. PC speaker was driven far beyond its original design and intention. Sound Blasters, and later built-in clones/compatibles, changed the general outlook of sound.

You'll see a shift to Adlib/SB audio start around 1987-1988, and by 1991 they were no longer niche. PC speaker support started to wane, but didn't entirely go away until Windows 95.

How do I remember this? I ran a BBS in the 90s, and my family was one of the early adopters of sound cards back in 1987 (Creative Music System, later rebranded to Game Blaster before Creative Labs came out with the Adlib-compatible Sound Blaster) and we ended up going through a few of the different cards over the years across multiple PCs.

I remember an old demo that would play a loop of the chorus of I Say a Little Prayer through the PC speaker. It was hard to believe that the speaker could be pushed to such limits.

I had an Amstrad PC1512 I will always remember because it had a volume control. It had some sort of powered speaker, so you could turn it up absurdly high, or lower the volume down reasonably (even switching it off)

This is not the exact model, but you can see the volume control here:

https://computers.popcorn.cx/amstrad/pc2086/pc2086-02.jpg

It was just a single pin on the timer chip connected to a buzzer so you could generate a square way at a certain frequency.

But you could do a bit more. Here’s a DOS golf game that did.

https://m.youtube.com/watch?v=hMPb1UlSRpY

Probably use software to implement pulse width modulation. I knew even 8-bit computers where people would bit-bang PWN to produce audio. Its just that storing all that data would be a major constraint in such limited computers.

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