I'm still rocking your old card and love it 😀 I must admit I didn't go through every single pages of this thread, can you maybe explain what your objectives are with this new card and what will be the major improvements over the existing one?

I hope to finish the new design today (assigning JLCPCB parts for the order, rechecking all connections, and finalizing the routing). The past two weeks have been quite busy, so I didn’t have much time to work on hobby projects.
I might pick up a Keystone bracket today to do a fit test with a paper prototype.

The new card is basically the same design, just polished a bit and optimized for manufacturing at JLCPCB. Some component part numbers were changed to better match parts available there.

I also added a dedicated oscillator instead of relying on the ISA bus clock, since a user reported that the sound could be slightly off on some systems.
The voltage divider on the PC speaker mix-in will be adjusted to allow higher loudness.

I'm also switching to a Keystone metal bracket. The old design was originally converted from Eagle CAD, which caused quite a few consistency issues when replacing parts, so starting from a clean layout seemed more reasonable.

I also noticed that JLCPCB now offers metal cutting and bending services. In the future it might even be possible to order the bracket directly from them.

These are amazing news. Keep up the great work!

holaplaneta wrote on Today, 10:29:

These are amazing news. Keep up the great work!

Seconded, glad to see the design is finished.

JAL

Amazing, thanks for the update and great work 😀