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Sounds from the Atari 8-bit computer line came through the RF video cable into your television much like video game systems from the time. The original Atari 400/800 also had a built in speaker, though from what I can tell it only produced the keyboard "click" sounds and wasn't meant to do anything else. I don't think the internal speaker was included in the later XL and XE lines.

Was the internal speaker of the original 400/800 usable for anything other than the keyboard click? That being said, how was it hooked up in the architecture? By this I mean was it tied to one of the POKEY channels (doubtful) or was there dedicated circuitry for the speaker?

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  • It's similar to the The ZX Spectrum 128K that had the sound channels via the TV and a buzzer in the computer. It was used by Tim Follin in the soundtrack for Chronos and Agent-X 2.
    – liftarn
    Oct 26, 2016 at 12:16

1 Answer 1

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The speaker was known as the console speaker and is controlled using the byte at location 53279; as indicated in Mapping the Atari:

POKEing any number from zero to eight will cause a click from the speaker.

The book also includes a program listing based on a COMPUTE! article, illustrating how to play different tones on the console speaker.

The Atari 400/800 service manual mentions specific circuitry on the motherboard, which

Provides the driving circuitry for the Key-Press signal from the Central Processing Unit PCB to the Console speaker.

(page 1-12). Page 1-18 of the service manual shows the Atari 400 motherboard block diagram; the keyboard speaker is connected to the CPU board via a connector jack (J106), and the circuit doesn't go through POKEY. Page 1-20 shows the same information for the Atari 800, with the same layout but a different number for the connector jack (J105).

The console speaker was removed in later systems; the key click was routed through the TV speaker and could be disabled (see the Atari 8-bit FAQ).

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  • I believe the game Ultima III employed the Atari's internal speaker, using it for "combat noises", so that there would be additional POKEY resources for the game music. Feb 8, 2018 at 11:58
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    Indeed @Crossfit_and_Beer, the difference between the built-in speaker and the POKEY music is clearly audible in this video! Feb 8, 2018 at 15:05
  • @ScottPrive Ultima III didn't use the internal speaker for combat noises. I played it for hours on end on my Atari 800 back in 83/84 and I remember distinctly that the combat noises came out of the TV speaker along with everything else. If you played it on a newer computer, where the "internal" speaker sounds also came out of the TV, I could see where you'd think the "internal" speaker was making the noises.
    – Jesse
    Feb 26, 2023 at 13:46
  • Having said that, the combat noises are very distinct and not something you'd normally hear coming from the POKEY. My theory was that U3 used the POKEY in "volume only" mode to create it's own waveforms and was a carry-over from the original Apple II version. The Apple II does not have a sound generating chip and the only was to make tones was to manually pulse the internal speaker at varying frequencies which is something the POKEY can do in volume-only mode.
    – Jesse
    Feb 26, 2023 at 13:46

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