The Prelude is a full length Zorro II 16bit sound card. It contains a 2K FIFO Cache, and a CSSC 4231A sound processor capable of playing ALaw, uLaw, 8bit, 16bit ADCPM encodings. The Prelude also contains a built-in sampler (full duplex) capable of recording at rates from 5.51Khz up to 64Khz. The Prelude has LINE IN, MIC IN (with built in amplifier), 2 x AUX IN, MONO IN, MONO OUT and an internal audio input. Several expansion modules are available for the Prelude including the Arpeggiator, the MPEGit and the Rombler.
The remake card gerbers have been made available via github. This includes all the files needed to send to a PCB manufacturer to have the blank boards made. I had mine made using JLCPCB. The cost was very reasonable and the quality of the boards is very good.
A Bill of Materials is included, but I discovered that it is incomplete missing some key items. Notably, the 3.5mm connectors, the 2k FIFO chips, 1000pF capacitors and 24 pin sockets.
Also, the GAL20V8B chips are no longer manufactured, you will either need to source alternatives, like the ALT20V8B or get a Time Machine.
When you find the GALs, they will also require programming. You will need to get a programmer as well.
Another chip you will have to source is the Crystal CS4231A-KL. This, too, is no longer manufactured. I sourced mine through eBay.
Some changes have been made to the design of the card. Originally, there was one connector with a pig tail adapter, this has been changed to four separate connectors on the card. A much cleaner design.
As of now, I have to source the GALs, and a programmer to complete the main board build.
The MPEGit board allows for the deciding of mpeg audio files. It supports Layer I and Layer II streams.
This is a welcome board in the community. I’m glad someone took the effort to reverse this board and make it available to the community.
There’s a lot of closed sourced projects and this needs to STOP! NOW! The Amiga platform will only continue to thrive by allowing them to be open for all to utilize.
16-Bit Revolution 
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