AQA released

[saimo]

I just released this...

AQA (Amiga Quality Audio) is (mainly) a collection of CPU-based audio playback tools for classic Amigas that stream stereo audio samples from mass storage devices through the Paula chip also at frequencies way beyond the canonical 28 kHz of the Amiga or the 44.1 kHz of CDs (e.g. 96 kHz), and with a resolution of 8 or 14 bits. AQA is therefore suitable for listening to high-quality music even on the good old classic Amigas.

Download: https://retream.itch.io/amiga-tools

Basic usage workflow:
1. save the audio data to listen to as uncompressed stereo 8- or 16-bit WAV files;
2. convert the WAV files to AQA files with cWAV*;
3. stream the AQA files with sAQA*.

Further details in the manual, which includes also some technical information for the curious ones.

[AmigaHope]

Originally Posted by saimo

I just released this...

AQA (Amiga Quality Audio) is (mainly) a collection of CPU-based audio playback tools for classic Amigas that stream stereo audio samples from mass storage devices through the Paula chip also at frequencies way beyond the canonical 28 kHz of the Amiga or the 44.1 kHz of CDs (e.g. 96 kHz), and with a resolution of 8 or 14 bits. AQA is therefore suitable for listening to high-quality music even on the good old classic Amigas.

Download: https://retream.itch.io/amiga-tools

Basic usage workflow:
1. save the audio data to listen to as uncompressed stereo 8- or 16-bit WAV files;
2. convert the WAV files to AQA files with cWAV*;
3. stream the AQA files with sAQA*.

Further details in the manual, which includes also some technical information for the curious ones.

Interesting, how does this compare in performance vs DMA audio on systems that can feed Paula samples at higher data rates (ECS Agnus/AGA Alice)?



It's cool that you can get high quality audio out of OCS using this!

[SkulleateR]

This reminds me of Forrest from back in the days : https://aminet.net/package/mus/misc/Forrest

... but in a modern way

Don´t really need it but I like the idea

[saimo]

Originally Posted by AmigaHope

Interesting, how does this compare in performance vs DMA audio on systems that can feed Paula samples at higher data rates (ECS Agnus/AGA Alice)?

DMA still couldn't go beyond 56 kHz, whereas the CPU can reach even crazy frequencies - here are some figures from the manual:

The following table shows the limits reached on a PAL Amiga 1200 with a Blizzard 1230 IV, mounting a 50 MHz 68030 and 60 ns RAM, and a CompactFlash connected to the internal IDE port.

+-----------------+-----------------+--------+-----------+
| EXPANSION BOARD : AQA FILE FORMAT : PERIOD : FREQUENCY |
+-----------------+-----------------+--------+-----------+
| disabled        : AQA0            :     30 : 118229.83 |
| disabled        : AQA1            :     37 :  95862.02 |
| disabled        : AQA2            :     41 :  86509.63 |
| enabled         : AQA0            :     11 : 322445.00 |
| enabled         : AQA1            :     16 : 221680.93 |
| enabled         : AQA2            :     17 : 208640.88 |
+-----------------+-----------------+--------+-----------+

(When the expansion board is disabled, the Amiga 1200 works as if it were a stock machine.)

The downside is that the CPU cannot do anything else in the meanwhile and that, at least from a certain point on, the DMA channels must be off (for example, the Hertz Overload demo keeps 6 bitplanes on and even scrolls a plane, but if I increased the frequency a bit beyond 70938 Hz, the audio would start to stutter on a stock A1200).

It's cool that you can get high quality audio out of OCS using this!

To be honest, I only have an AGA machine, so I never tested the tools on OCS or ECS. Bugs aside (if any), there's no reason why they shouldn't work on those chipsets, though. Also, the heavier fixed filter found on Amigas other the Amiga 1200 and the Amiga CD32 will inevitably work against the high frequencies allowed by AQA.

[saimo]

Originally Posted by SkulleateR

This reminds me of Forrest from back in the days : https://aminet.net/package/mus/misc/Forrest

... but in a modern way

Don´t really need it but I like the idea

I didn't know about Forrest.

It's different though: Forrest is "just" a MPEG->8SVX converter.

[SkulleateR]

Originally Posted by saimo

It's different though: Forrest is "just" a MPEG->8SVX converter.

That´s why I said "reminds me of" because the overall goal is the same, listen to music on low end systems

[saimo]

Originally Posted by SkulleateR

That´s why I said "reminds me of" because the overall goal is the same, listen to music on low end systems

I see and I'm fine with you seeing it like that
However, I need to point out that AQA's goal is to allow listening to music (or any other audio data in general) at (stupidly) high frequencies - without the second part, AQA wouldn't exist